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| 1. | Finite element simulations of smart fracture plates capable of cyclic shortening and lengthening: which stroke for which fracture?Front Bioeng Biotechnol. 2024 Jul 23:12:1420047. doi: 10.3389/fbioe.2024.1420047. eCollection 2024. AuthorsMichael Roland 1 , Stefan Diebels 1 , Kerstin Wickert 1 , Tim Pohlemann 2 , Bergita Ganse 2 3 Affiliations
AbstractIntroduction: Bone healing can be improved by axial micromovement, as has been shown in animals and human patients with external fixators. In the development of smart fracture plates, the ideal amount of stroke for different fracture types in the different healing stages is currently unknown. It was hypothesized that the resulting strain in the fracture gap of a simple tibial shaft fracture does not vary with the amount of axial stroke in the plate, the fracture gap size, and the fracture angle. Methods: With finite element simulations based on body donation computed tomography data, the second invariant of the deviatoric strain tensor (J2), strain energy density, hydrostatic strain, octahedral shear strain, and percentage of the fracture gap in the "perfect healing window" were computed for different gap sizes (1-3 mm), angles (5°-60°), and plate stroke levels (0.05-0.60 mm) in three healing stages. Multiple linear regression analyses were performed. Results: Findings showed that an active fracture plate should deliver an axial stroke in the range of 0.10-0.45 mm. Different optimal stroke values were found for each healing phase, namely, 0.10-0.25 mm for the first, 0.10 mm for the second, and 0.35-0.45 mm for the third healing phase, depending on the fracture gap size and less on the fracture angle. J2, hydrostatic strain, octahedral shear strain and the strain energy density correlated with the fracture gap size and angle (all p < 0.001). The influence of the fracture gap size and angle on the variability (adjusted R2) in several outcome measures in the fracture gap was shown to vary throughout healing. The contribution to the variability of the percentage of the fracture gap in the perfect healing window was greatest during the second healing phase. For J2, strain energy density, hydrostatic strain, and octahedral shear strain, the fracture gap size showed the greatest contribution in the third fracture healing phase, while the influence of fracture angle was independent of the healing phase. Discussion: The present findings are relevant for implant development and to design clinical studies that aim to accelerate fracture healing using axial micromovement. Keywords: active implant; biomechanics; bone regeneration; computer simulation; digital health; fracture healing; osteosynthesis; smart implant. Copyright © 2024 Roland, Diebels, Wickert, Pohlemann and Ganse. Conflict of interest statementTP is president and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopaedic Trauma Surgery (DGU), the German Society of Orthopaedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defence. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest Full text links |
| 2. | [National challenges for trauma surgery in Germany due to violence and war]Unfallchirurgie (Heidelb). 2024 Jul;127(7):492-499. doi: 10.1007/s00113-024-01442-0. Epub 2024 Jun 11. [Article in German] AuthorsAxel Franke 1 2 , Dan Bieler 3 , Wolfgang Lehmann 4 , Tim Pohlemann 5 , Benedikt Friemert 6 , Gerhard Achatz 7 Affiliations
AbstractDue to the war in Ukraine and the treatment of patients with war wounds in the hospitals of the TraumaNetworks of the German Society for Trauma Surgery (TraumaNetzwerke DGU®), injuries from life-threatening mission situations (LebEL), terrorism, violence and war have become a matter of daily professional life. Furthermore, the societal and global feeling of security has fundamentally changed. The much-cited term "turning point in history", the reorientation of the Armed Forces and the investigation of the resilience of the healthcare system with respect to the "fitness for war", approximate to the description of the current challenges for trauma surgery (UCH) in Germany. Based on the developments following the terrorist attacks in Paris in 2015 and in Brussels in 2016, a clarification is given as to which adaptations have already been successful and how quickly an improvement could successfully be achieved. In this context, the concept of tactical care and the course on Terror and Disaster Surgical Care (TDSC), for example, have been game changing. The main challenge currently lies in overcoming the structural alterations in the German healthcare system and professionally in the treatment of war wounded personnel from Ukraine. The knowledge gained from these two national tasks must be analyzed for the future development and adaptation of established treatment structures, e.g., of the TraumaNetzwerke DGU®, under the requirements of the increased resilience against war, terrorism and violence. The aim is to name that which has already been achieved with respect to the national challenges for UCH and at the same time to outline or discuss further necessities for improvements and elimination of possible gaps in capabilities. Durch den Krieg in der Ukraine und die Behandlung der Kriegsverletzten in den Kliniken der TraumaNetzwerke der Deutschen Gesellschaft für Unfallchirurgie (TraumaNetzwerke DGU®) sind Verletzungen durch lebensbedrohliche Einsatzlagen (LebEL), Terror, Gewalt und Krieg zum Gegenstand des täglichen fachlichen Lebens geworden. Darüber hinaus hat sich das gesellschaftliche und globale Sicherheitsgefühl grundlegend verändert. Der viel zitierte Begriff „Zeitenwende“, die Neuausrichtung der Bundeswehr und die Überprüfung der Resilienz des Gesundheitssystems bezüglich der „Kriegstüchtigkeit“ legen die Beschreibung der aktuellen Herausforderungen für die Unfallchirurgie (UCH) in Deutschland nahe. Anhand der Entwicklungen nach den Terroranschlägen von Paris 2015 und Brüssel 2016 wird erläutert, welche Anpassungen bereits erfolgt sind, und wie erfolgreich zeitnah eine Verbesserung erreicht werden konnte. Hier sind z. B. das Konzept der taktischen Versorgung und der Kurs Terror and Disaster Surgical Care (TDSC) wegweisend gewesen. Aktuell besteht die Hauptherausforderung in der Bewältigung der Strukturveränderungen des deutschen Gesundheitssystems und fachlich in der Versorgung der Kriegsverletzten aus der Ukraine. Die Erkenntnisse aus diesen beiden nationalen Aufgaben gilt es, für die zukünftige Weiterentwicklung und Anpassung etablierter Versorgungsstrukturen, wie z. B. der TraumaNetzwerke DGU®, unter den Erfordernissen der Resilienzsteigerung gegenüber Krieg, Terror und Gewalt zu analysieren. Es ist das Ziel, bereits Erreichtes bezüglich der nationalen Herausforderungen für die UCH zu benennen sowie gleichzeitig weitere Notwendigkeiten für eine Verbesserung und die Beseitigung von möglichen Fähigkeitslücken zu skizzieren bzw. zu diskutieren. Keywords: Disaster planning; Healthcare; Humanitarian aid; Life-threatening event; Terrorism. © 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature. |
| 3. | Characteristic Changes of the Stance-Phase Plantar Pressure Curve When Walking Uphill and Downhill: Cross-Sectional StudyJ Med Internet Res. 2024 May 8:26:e44948. doi: 10.2196/44948. AuthorsChristian Wolff 1 , Patrick Steinheimer 2 , Elke Warmerdam 3 , Tim Dahmen 1 , Philipp Slusallek 1 , Christian Schlinkmann 1 , Fei Chen 1 , Marcel Orth 2 , Tim Pohlemann 2 , Bergita Ganse 2 3 Affiliations
AbstractBackground: Monitoring of gait patterns by insoles is popular to study behavior and activity in the daily life of people and throughout the rehabilitation process of patients. Live data analyses may improve personalized prevention and treatment regimens, as well as rehabilitation. The M-shaped plantar pressure curve during the stance phase is mainly defined by the loading and unloading slope, 2 maxima, 1 minimum, as well as the force during defined periods. When monitoring gait continuously, walking uphill or downhill could affect this curve in characteristic ways. Objective: For walking on a slope, typical changes in the stance phase curve measured by insoles were hypothesized. Methods: In total, 40 healthy participants of both sexes were fitted with individually calibrated insoles with 16 pressure sensors each and a recording frequency of 100 Hz. Participants walked on a treadmill at 4 km/h for 1 minute in each of the following slopes: -20%, -15%, -10%, -5%, 0%, 5%, 10%, 15%, and 20%. Raw data were exported for analyses. A custom-developed data platform was used for data processing and parameter calculation, including step detection, data transformation, and normalization for time by natural cubic spline interpolation and force (proportion of body weight). To identify the time-axis positions of the desired maxima and minimum among the available extremum candidates in each step, a Gaussian filter was applied (σ=3, kernel size 7). Inconclusive extremum candidates were further processed by screening for time plausibility, maximum or minimum pool filtering, and monotony. Several parameters that describe the curve trajectory were computed for each step. The normal distribution of data was tested by the Kolmogorov-Smirnov and Shapiro-Wilk tests. Results: Data were normally distributed. An analysis of variance with the gait parameters as dependent and slope as independent variables revealed significant changes related to the slope for the following parameters of the stance phase curve: the mean force during loading and unloading, the 2 maxima and the minimum, as well as the loading and unloading slope (all P<.001). A simultaneous increase in the loading slope, the first maximum and the mean loading force combined with a decrease in the mean unloading force, the second maximum, and the unloading slope is characteristic for downhill walking. The opposite represents uphill walking. The minimum had its peak at horizontal walking and values dropped when walking uphill and downhill alike. It is therefore not a suitable parameter to distinguish between uphill and downhill walking. Conclusions: While patient-related factors, such as anthropometrics, injury, or disease shape the stance phase curve on a longer-term scale, walking on slopes leads to temporary and characteristic short-term changes in the curve trajectory. Keywords: baropedography; digital health; gait; gait analysis; ground reaction forces; injury; monitoring; movement; movement analysis; pedography; personalized medicine; podiatric medicine; podiatry; postoperative treatment; rehabilitation; sensor; sensors; slope; treatment; wearables. ©Christian Wolff, Patrick Steinheimer, Elke Warmerdam, Tim Dahmen, Philipp Slusallek, Christian Schlinkmann, Fei Chen, Marcel Orth, Tim Pohlemann, Bergita Ganse. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 08.05.2024. Conflict of interest statementConflicts of Interest: TP is President and Board Member of the AO-Foundation, Switzerland, and Extended Board Member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the Medical Advisory Board of the German Ministry of Defence. The other authors do not have a conflict of interest. Full text links |
| 4. | Experimental and virtual testing of bone-implant systems equipped with the AO Fracture Monitor with regard to interfragmentary movementFront Bioeng Biotechnol. 2024 Mar 8:12:1370837. doi: 10.3389/fbioe.2024.1370837. eCollection 2024. AuthorsKerstin Wickert 1 , Michael Roland 1 , Annchristin Andres 1 , Stefan Diebels 1 , Bergita Ganse 2 , Dorothea Kerner 3 , Felix Frenzel 3 , Thomas Tschernig 4 , Manuela Ernst 5 , Markus Windolf 5 , Max Müller 6 , Tim Pohlemann 6 , Marcel Orth 6 Affiliations
AbstractIntroduction: The management of fractured bones is a key domain within orthopedic trauma surgery, with the prevention of delayed healing and non-unions forming a core challenge. This study evaluates the efficacy of the AO Fracture Monitor in conjunction with biomechanical simulations to better understand the local mechanics of fracture gaps, which is crucial for comprehending mechanotransduction, a key factor in bone healing. Through a series of experiments and corresponding simulations, the study tests four hypotheses to determine the relationship between physical measurements and the predictive power of biomechanical models. Methods: Employing the AO Fracture Monitor and Digital Image Correlation techniques, the study demonstrates a significant correlation between the surface strain of implants and interfragmentary movements. This provides a foundation for utilizing one-dimensional AO Fracture Monitor measurements to predict three-dimensional fracture behavior, thereby linking mechanical loading with fracture gap dynamics. Moreover, the research establishes that finite element simulations of bone-implant systems can be effectively validated using experimental data, underpinning the accuracy of simulations in replicating physical behaviors. Results and Discussion: The findings endorse the combined use of monitoring technologies and simulations to infer the local mechanical conditions at the fracture site, offering a potential leap in personalized therapy for bone healing. Clinically, this approach can enhance treatment outcomes by refining the assessment precision in trauma trials, fostering the early detection of healing disturbances, and guiding improvements in future implant design. Ultimately, this study paves the way for more sophisticated patient monitoring and tailored interventions, promising to elevate the standard of care in orthopedic trauma surgery. Keywords: biomechanical simulation; bone healing; experimental biomechanics; orthopedic trauma surgery; osteosynthesis; patient monitoring; smart implant. Copyright © 2024 Wickert, Roland, Andres, Diebels, Ganse, Kerner, Frenzel, Tschernig, Ernst, Windolf, Müller, Pohlemann and Orth. Conflict of interest statementTP is president and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defense. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 5. | Long-term continuous instrumented insole-based gait analyses in daily life have advantages over longitudinal gait analyses in the lab to monitor healing of tibial fracturesFront Bioeng Biotechnol. 2024 Mar 1:12:1355254. doi: 10.3389/fbioe.2024.1355254. eCollection 2024. AuthorsElke Warmerdam 1 , Christian Wolff 2 , Marcel Orth 3 , Tim Pohlemann 3 , Bergita Ganse 1 3 Affiliations
AbstractIntroduction: Monitoring changes in gait during rehabilitation allows early detection of complications. Laboratory-based gait analyses proved valuable for longitudinal monitoring of lower leg fracture healing. However, continuous gait data recorded in the daily life may be superior due to a higher temporal resolution and differences in behavior. In this study, ground reaction force-based gait data of instrumented insoles from longitudinal intermittent laboratory assessments were compared to monitoring in daily life. Methods: Straight walking data of patients were collected during clinical visits and in between those visits the instrumented insoles recorded all stepping activities of the patients during daily life. Results: Out of 16 patients, due to technical and compliance issues, only six delivered sufficient datasets of about 12 weeks. Stance duration was longer (p = 0.004) and gait was more asymmetric during daily life (asymmetry of maximal force p < 0.001, loading slope p = 0.001, unloading slope p < 0.001, stance duration p < 0.001). Discussion: The differences between the laboratory assessments and the daily-life monitoring could be caused by a different and more diverse behavior during daily life. The daily life gait parameters significantly improved over time with union. One of the patients developed an infected non-union and showed worsening of force-related gait parameters, which was earlier detectable in the continuous daily life gait data compared to the lab data. Therefore, continuous gait monitoring in the daily life has potential to detect healing problems early on. Continuous monitoring with instrumented insoles has advantages once technical and compliance problems are solved. Keywords: digital medicine; fracture; ground reaction force; injury; pedography; postoperative treatment; rehabilitation; wearable sensors. Copyright © 2024 Warmerdam, Wolff, Orth, Pohlemann and Ganse. Conflict of interest statementTP is president and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defence. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 6. | Reappraisal of clinical trauma trials: the critical impact of anthropometric parameters on fracture gap micro-mechanics-observations from a simulation-based studySci Rep. 2023 Nov 22;13(1):20450. doi: 10.1038/s41598-023-47910-2. AuthorsMichael Roland 1 , Stefan Diebels 2 , Marcel Orth 3 , Tim Pohlemann 3 , Bertil Bouillon 4 , Thorsten Tjardes 4 Affiliations
AbstractThe evidence base of surgical fracture care is extremely sparse with only few sound RCTs available. It is hypothesized that anthropometric factors relevantly influence mechanical conditions in the fracture gap, thereby interfering with the mechanoinduction of fracture healing. Development of a finite element model of a tibia fracture, which is the basis of an in silico population (n = 300) by systematic variation of anthropometric parameters. Simulations of the stance phase and correlation between anthropometric parameters and the mechanical stimulus in the fracture gap. Analysis of the influence of anthropometric parameters on statistical dispersion between in silico trial cohorts with respect to the probability to generate two, with respect to anthropometric parameters statistically different trial cohorts, given the same power assumptions. The mechanical impact in the fracture gap correlates with anthropometric parameters; confirming the hypothesis that anthropometric factors are a relevant entity. On a cohort level simulation of a fracture trial showed that given an adequate power the principle of randomization successfully levels out the impact of anthropometric factors. From a clinical perspective these group sizes are difficult to achieve, especially when considering that the trials takes advantage of a "laboratory approach ", i.e. the fracture type has not been varied, such that in real world trials the cohort size have to be even larger to level out the different configurations of fractures gaps. Anthropometric parameters have a significant impact on the fracture gap mechanics. The cohort sizes necessary to level out this effect are difficult or unrealistic to achieve in RCTs, which is the reason for sparse evidence in orthotrauma. New approaches to clinical trials taking advantage of modelling and simulation techniques need to be developed and explored. © 2023. The Author(s). Conflict of interest statementThe authors declare no competing interests. Full text links |
| 7. | Improved weight bearing during gait at 6 weeks post-surgery with an angle stable locking system after distal tibial fractureGait Posture. 2024 Jan:107:169-176. doi: 10.1016/j.gaitpost.2023.09.013. Epub 2023 Sep 27. AuthorsAlison N Agres 1 , Sónia A Alves 1 , Dankward Höntzsch 2 , René El Attal 3 , Tim Pohlemann 4 , Klaus-Dieter Schaser 5 , Alexander Joeris 6 , Denise Hess 7 , Georg N Duda 8 Affiliations
AbstractBackground: Functional recovery after intramedullary nailing of distal tibial fractures can be monitored using ipsilateral vertical ground reaction forces (vGRF), giving insight into recovery of patients' gait symmetry. Previous work compared patient cohorts to healthy controls, but it remains unclear if these metrics can identify treatment-based differences in return to function post-surgery. Research question: Is treatment of a distal tibial fracture with intramedullary nailing with an angle stable locking system (ASLS) associated with higher ipsilateral vGRF and improved symmetry compared to conventional intramedullary nailing at an early time point? Methods: Thirty-nine patients treated with ASLS intramedullary nailing were retrospectively compared to thirty-nine patients with conventional locking. vGRFs were collected at 1, 6, 12, 26, and 52 weeks post-surgery during standing and gait. Discrete metrics of ipsilateral vGRF (maximal force, impulse) and asymmetry were compared between treatments at each time point. Time-scale comparisons of ipsilateral vGRF and lower limb asymmetry were additionally performed for gait trials. Mann-Whitney Test or a two-way analysis of variance tested discrete comparisons; statistical non-parametric mapping tested time-scale data between treatment groups. Results: During gait, ASLS-treated patients applied more load on the operated limb (17-38% stance, p = 0.015) and consequently loaded limbs more symmetrically (8-37% stance, p = 0.008) during the loading response at 6 weeks post-surgery compared to conventional IM treatment. Discrete measures of symmetry at the same time point identified treatment-based differences in maximal force (p = 0.039) and impulse (p = 0.012), with ASLS-treated patients exhibiting more symmetry. No differences were identified in gait trials at later time points nor from all standing trials. Significance: During the initial loading response of gait, increased ipsilateral vGRF and improved weightbearing symmetry were identified in ASLS patients at 6 weeks post-surgery compared to conventional IM nailing. Early and objective metrics of dynamic movement are suggested to identify treatment-based differences in functional recovery. Keywords: Fracture fixation; Gait analysis; Ground reaction force; Intermedullary nail; Tibia fracture. Copyright © 2023 Elsevier B.V. All rights reserved. Conflict of interest statementDeclaration of Competing Interest A.A., S.A., R.E.A., K-D.S., G.D. have no conflicts of interests to declare. D. Höntzsch serves as a consultant at the AO, Member of the AO technical Commission. Consultant of DePuy Synthes, Ceramtec, Rimasys. TP was head of the AO Foundation TK system when the study was initiated and partially funded by the TK-System. A.J. and D. Hess are employees in the AO Foundation. Full text links |
| 8. | "Fall Risk Scoring" in Outpatient Gait Analysis: Validation of a New Fall Risk Assessment for Nursing Home ResidentsZ Orthop Unfall. 2023 Oct 9. doi: 10.1055/a-2151-4709. Online ahead of print. [Article in English, German] AuthorsEduard Witiko Unger 1 , Tim Pohlemann 1 , Marcel Orth 1 , Mika F R Rollmann 2 , Maximilian M Menger 2 , Steven C Herath 2 , Tina Histing 3 , Benedikt J Braun 3 Affiliations
AbstractFalls in senior home residents are common. Individual preventive training can lower the fall risk. To detect the need for training, a systematic assessment of the individual fall risk is needed. The aim of this study was thus to assess whether a fall risk score based on free field insole measurements can distinguish between an at-risk group of senior home residents and a healthy young control group. A published fall risk score was used in senior home residents over the age of 75 and a young (< 40 years) control group to determine the individual fall risk. In addition, the fall events over 12 months were assessed. Statistical analysis including ROC analysis was performed to determine the ability of the score to detect participants at heightened fall risk. In total, 18 nursing home residents and 9 young control participants were included. Of the nursing home residents, 15 had at least one fall, with a total of 37 falls recorded over 12 months. In the control group, no falls were recorded. The fall risk score was significantly different between nursing home residents and the control group (9.2 + 3.2 vs. 5.7 ± 2.2). Furthermore, the score significantly differentiated fallers from non-fallers (10.3 ± 1.8 vs. 5.2 ± 2.5), with a cut-off > 7.5 (AUC: 0.95) and a sensitivity of 86.7% (specificity 83.3%). The fall risk score is able to detect the difference between senior nursing home residents and young, healthy controls, as well as between fallers and non-fallers. Its main proof of concept is demonstrated, as based on movement data outside special gait labs, and it can simplify the risk of fall determination in geriatric nursing home residents and can now be used in further, prospective studies. Stürze von älteren Heimbewohnern sind häufig. Individuelle Prävention kann die Wahrscheinlichkeit zu stürzen senken. Um den Präventionsbedarf zu erkennen, bedarf es einer systematischen Erfassung des individuellen Sturzrisikos. In dieser Studie soll daher untersucht werden, inwiefern ein Sturzrisikoscore, gebildet aus mit einer erhöhten Sturzneigung assoziierten Gangparametern, zwischen einer hoch sturzgefährdeten Gruppe und einer jungen gesunden Kontrollgruppe unterscheiden kann. Ein bereits publizierter Sturzrisikoscore wurde bei über 75-jährigen, sturzgefährdeten Heimbewohnern sowie bei einer jungen, gesunden unter 40-jährigen Kontrollgruppe angewendet und ein individueller Score gebildet. Zusätzlich wurden die Sturzereignisse über einen Zeitraum von 12 Monaten erfasst. Nach Prüfung auf Normalverteilung wurde mittels Mittelwertvergleich und ROC-Analyse die Möglichkeit, Teilnehmer mithilfe des Scores zwischen älteren sturzgefährdeten Teilnehmern und jungen, gesunden Personen zu differenzieren, getestet. Es wurden 18 Heimbewohner und 9 junge, gesunde Teilnehmer in die Analyse einbezogen. Unter den Älteren stürzten 15 mindestens einmal, wobei insgesamt 37 Stürze innerhalb der 12 Monate erfasst wurden (2,06 ± 2,16; Range: 0–8). Unter den Jüngeren stürzte niemand. Dabei unterschied sich der Sturzrisikoscore der Heimbewohner von dem der Jüngeren signifikant (9,2 ± 3,2 vs. 5,7 ± 2,2). Ebenso unterschied sich der Score zwischen Gestürzten und nicht Gestürzten signifikant (10,3 ± 1,8 vs. 5,2 ± 2,5). Die Gestürzten und nicht Gestürzten konnte der Score mit einem Cut-off > 7,5 (AUC: 0,95) und einer Sensitivität von 86,7% differenzieren (Spezifität: 83,3%). Der gebildete Score erlaubt grundsätzlich die Differenzierung zwischen älterem und jüngerem Studienkollektiv, wie auch zwischen Gestürzten und nicht Gestürzten. Der gebildete Score basiert auf Bewegungsdaten, die außerhalb spezieller Ganglabore erhoben wurden, kann die Detektion von sturzrisikogefährdeten Heimbewohnern erleichtern und nun in prospektiven Studien weiter etabliert werden. Thieme. All rights reserved. Conflict of interest statementDie Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht. Full text links |
| 9. | A novel minimally invasive and press-fit method for symphysiodesis - a biomechanical analysisJ Exp Orthop. 2023 Sep 28;10(1):98. doi: 10.1186/s40634-023-00660-6. AuthorsTobias Fritz 1 , Marcel Orth 2 , Sascha J Hopp 2 3 , Jeremy Briem 2 4 , Jill Hahner 2 , David Osche 2 , Tim Pohlemann 2 , Antonius Pizanis 2 Affiliations
AbstractPurpose: Does the cylindrical shaped bone block allow a stable construct for the arthrodesis of the pubic symphysis compared to a rectangular shaped bone block. The cylindrical shaped bone block stabilized by a 3.5 symphyseal plate is inferior to the stabilization with an internal fixator. Methods: This study analyzed the arthrodesis of the pubic symphysis on 24 synthetic pelvises, using a rectangular shaped bone block (control group) or a cylindrical shaped bone block, stabilized with a symphysis locking plate (n = 8) as the standard clinical procedure. Additionally we analyzed the stability using an internal fixator. Results: This study showed that utilizing a cylindrical shaped synthetic bone graft results in a significant higher contact area and compression force compared to the classical rectangular shaped graft. Furthermore, the stabilization with an internal fixator had the tendency for increases of compression force and contact area, yet without a statistical significance, when compared to the plate fixation. Conclusion: The novel method of cylindrical symphysis resection and cylindrical bone block implantation allowed an increased biomechanical stability compared to using a classical rectangular bone graft, also resulting in higher contact area. Moreover, this technique would also allow a minimally invasive approach for this purpose, which in turn could preserve perisymphyseal ligaments, thereby improving healing in a clinical context. Keywords: Arthrodesis symphysis; Bone transplant; Internal fixator; Pubic symphysis; Symphysiodesis; Symphysis. © 2023. European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA). Conflict of interest statementNone. Full text links |
| 10. | Lower oxygen saturation with higher rates of norepinephrine in bone fractures of polytrauma patients: a pilot studyCrit Care. 2023 Sep 25;27(1):367. doi: 10.1186/s13054-023-04657-6. AuthorsLaura Koch 1 , Marcel Orth 2 , Tobias Fink 3 , Andreas Meiser 3 , Thomas Volk 3 , Michael D Menger 4 , Matthias W Laschke 4 , Torsten Pastor 5 , Matthias Knobe 6 7 8 , Tim Pohlemann 2 , Bergita Ganse 9 10 Affiliations
No abstract available Keywords: Catecholamines; Fracture healing; Injury; Mean arterial pressure; Microcirculation; Multiple trauma; Non-union; Noradrenaline; O2C; Perfusion. Conflict of interest statementTP is president and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopaedic Trauma Surgery (DGU), the German Society of Orthopaedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defence. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 11. | [Clavicle fractures: practical approach in clinical routine]Chirurgie (Heidelb). 2023 Dec;94(12):1045-1056. doi: 10.1007/s00104-023-01958-y. Epub 2023 Sep 13. [Article in German] AuthorsM Müller 1 , Y Bullinger 2 , T Pohlemann 2 , M Orth 2 Affiliations
AbstractFractures of the clavicle are among the most common fractures. They typically result from a fall onto the lateral shoulder or the extended arm and are often related to sports and bicycle accidents. Obtaining the exact trauma mechanism, proper clinical findings and adequate X‑rays usually lead to the correct diagnosis. Non-displacement fractures can be treated conservatively with good results. Unstable and displaced fractures should be treated operatively. Open fractures or looming penetration are emergencies und should be treated immediately. In addition to fracture classification and morphology, other factors such as additional injuries and patient-related factors need to be considered in order to make an individualized therapy decision. In operative treatment, angular stable plating is the therapy of choice, and in most cases early functional aftercare is possible. Die Klavikulafraktur ist eine der häufigsten Frakturen des Menschen. Typische Unfallmechanismen sind Stürze auf die Schulter oder den ausgestreckten Arm, häufig bei Sport- oder Zweiradunfällen. Auf Basis einer genauen Anamnese, zielgerichteten klinischen Untersuchung und adäquaten Röntgendiagnostik kann meist die Diagnose gestellt werden. Bei nichtdislozierten Frakturen führt die konservative Therapie in der Regel zu guten Ergebnissen. Bei dislozierten, instabilen Frakturen sollte die Indikation zur operativen Versorgung gestellt werden. Offene Verletzungen sowie eine drohende Durchspießung stellen Notfallindikationen dar. Neben der Frakturklassifikation und -morphologie spielen auch andere Faktoren eine Rolle bei der individuellen Therapieentscheidung, so etwa bestehende Begleitverletzungen und patientInnenspezifische Faktoren (Alter, Komorbiditäten, funktioneller Anspruch). Bei der operativen Versorgung ist die Plattenosteosynthese die Therapie der Wahl, meist kann eine funktionelle Nachbehandlung erfolgen. Keywords: Clavicle fracture, displaced; Clavicle fracture, pediatric; Clavicle fracture/Treatment algorithm; Non union; Plate osteosynthesis. © 2023. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature. |
| 12. | Both-Column Acetabular Fractures: Does Surgical Approach Vary Based on Using Virtual 3D Reconstructions?Diagnostics (Basel). 2023 May 5;13(9):1629. doi: 10.3390/diagnostics13091629. AuthorsJudith F Leemhuis 1 , Nick Assink 1 2 , Inge H F Reininga 1 , Jean-Paul P M de Vries 1 , Kaj Ten Duis 1 , Anne M L Meesters 1 2 , Frank F A IJpma 1 ; The Pelvic Fracture Consortium Collaborators
Affiliations
AbstractDisplacement of the anterior and posterior column complicates decision making for both-column acetabular fractures. We questioned whether pelvic surgeons agree on treatment strategy, and whether the use of virtual 3D reconstructions changes the treatment strategy of choice. A nationwide cross-sectional survey was performed in all pelvic trauma centers in the Netherlands. Twenty surgeons assessed 15 both-column fractures in 2D as well as 3D. Based on conventional imaging, surgical treatment was recommended in 89% of cases, and by adding 3D reconstructions this was 93% (p = 0.09). Surgical approach was recommended as anterior (65%), posterior (8%) or combined (27%) (poor level of agreement, κ = 0.05) based on conventional imaging. The approach changed in 37% (p = 0.006), with most changes between a combined and anterior approach (still poor level of agreement, κ = 0.13) by adding 3D reconstructions. Additionally, surgeons' level of confidence increased from good in 38% to good in 50% of cases. In conclusion, surgeons do not agree on the treatment strategy for both-column acetabular fractures. Additional information given by 3D reconstructions may change the chosen surgical approach and increase surgeons' confidence about their treatment decision. Therefore, virtual 3D reconstructions are helpful for assessing both-column fracture patterns and aid in the choice of treatment strategy. Keywords: 3D; acetabular fracture; acetabulum; both column; surgical approach; survey; three-dimensional. Conflict of interest statementThe authors declare no conflict of interest. Full text links |
| 13. | Occurrence, resistance patterns, and management of carbapenemase-producing bacteria in war-wounded refugees from UkraineInt J Infect Dis. 2023 Jul:132:89-92. doi: 10.1016/j.ijid.2023.04.394. Epub 2023 Apr 16. AuthorsFabian K Berger 1 , Georges P Schmartz 2 , Tobias Fritz 3 , Nils Veith 3 , Farah Alhussein 1 , Sophie Roth 1 , Sophie Schneitler 1 , Thomas Gilcher 4 , Barbara C Gärtner 1 , Vakhtang Pirpilashvili 3 , Tim Pohlemann 3 , Andreas Keller 2 , Jacqueline Rehner 1 , Sören L Becker 5 Affiliations
Free article AbstractWe analyzed consecutive clinical cases of infections due to carbapenemase-producing gram-negative bacteria detected in war-wounded patients from Ukraine who were treated at one university medical center in southwest Germany between June and December 2022. The isolates of multiresistant gram-negative bacteria were subjected to a thorough microbiological characterization and whole genome sequencing (WGS). We identified five war-wounded Ukrainian patients who developed infections with New Delhi metallo-β-lactamase 1-positive Klebsiella pneumoniae. Two isolates also carried OXA-48 carbapenemases. The bacteria were resistant to novel antibiotics, such as ceftazidime/avibactam and cefiderocol. The used treatment strategies included combinations of ceftazidime/avibactam + aztreonam, colistin, or tigecycline. WGS suggested transmission during primary care in Ukraine. We conclude that there is an urgent need for thorough surveillance of multiresistant pathogens in patients from war zones. Keywords: Antimicrobial resistance; Carbapenemase; Cefiderocol; Ceftazidime/avibactam; Klebsiella pneumoniae; Pseudomonas aeruginosa. Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved. Conflict of interest statementDeclaration of competing interest Fabian K. Berger has received consultant fees from MSD and Pfizer (pertaining both to Clostridioides difficile). B.C. Gärtner has received honoraria from Pfizer, outside the submitted work. S.L. Becker has received speaker fees and advisory board participation fees from Pfizer (pertaining to ceftazidime/avibactam) and Shionogi (pertaining to cefiderocol). All other authors have no competing interests to declare. Full text links |
| 14. | Simulation-based prediction of bone healing and treatment recommendations for lower leg fractures: Effects of motion, weight-bearing and fibular mechanicsFront Bioeng Biotechnol. 2023 Feb 20:11:1067845. doi: 10.3389/fbioe.2023.1067845. eCollection 2023. AuthorsMarcel Orth 1 , Bergita Ganse 1 2 , Annchristin Andres 3 , Kerstin Wickert 3 , Elke Warmerdam 2 , Max Müller 1 , Stefan Diebels 3 , Michael Roland 3 , Tim Pohlemann 1 Affiliations
AbstractDespite recent experimental and clinical progress in the treatment of tibial and fibular fractures, in clinical practice rates of delayed bone healing and non-union remain high. The aim of this study was to simulate and compare different mechanical conditions after lower leg fractures to assess the effects of postoperative motion, weight-bearing restrictions and fibular mechanics on the strain distribution and the clinical course. Based on the computed tomography (CT) data set of a real clinical case with a distal diaphyseal tibial fracture, a proximal and a distal fibular fracture, finite element simulations were run. Early postoperative motion data, recorded via an inertial measuring unit system and pressure insoles were recorded and processed to study strain. The simulations were used to compute interfragmentary strain and the von Mises stress distribution of the intramedullary nail for different treatments of the fibula, as well as several walking velocities (1.0 km/h; 1.5 km/h; 2.0 km/h) and levels of weight-bearing restriction. The simulation of the real treatment was compared to the clinical course. The results show that a high postoperative walking speed was associated with higher loads in the fracture zone. In addition, a larger number of areas in the fracture gap with forces that exceeded beneficial mechanical properties longer was observed. Moreover, the simulations showed that surgical treatment of the distal fibular fracture had an impact on the healing course, whereas the proximal fibular fracture barely mattered. Weight-bearing restrictions were beneficial in reducing excessive mechanical conditions, while it is known that it is difficult for patients to adhere to partial weight-bearing recommendations. In conclusion, it is likely that motion, weight bearing and fibular mechanics influence the biomechanical milieu in the fracture gap. Simulations may improve decisions on the choice and location of surgical implants, as well as give recommendations for loading in the postoperative course of the individual patient. Keywords: biomechanics; fibula; finite element analysis; gait analysis; lower leg injury; motion; prognosis of bone healing; tibial fracture. Copyright © 2023 Orth, Ganse, Andres, Wickert, Warmerdam, Müller, Diebels, Roland and Pohlemann. Conflict of interest statementTP is president elect and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defense. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 15. | Effects of age, body height, body weight, body mass index and handgrip strength on the trajectory of the plantar pressure stance-phase curve of the gait cycleFront Bioeng Biotechnol. 2023 Feb 15:11:1110099. doi: 10.3389/fbioe.2023.1110099. eCollection 2023. AuthorsChristian Wolff 1 , Patrick Steinheimer 2 , Elke Warmerdam 3 , Tim Dahmen 1 , Philipp Slusallek 1 , Christian Schlinkmann 1 , Fei Chen 1 , Marcel Orth 2 , Tim Pohlemann 2 , Bergita Ganse 2 3 Affiliations
AbstractThe analysis of gait patterns and plantar pressure distributions via insoles is increasingly used to monitor patients and treatment progress, such as recovery after surgeries. Despite the popularity of pedography, also known as baropodography, characteristic effects of anthropometric and other individual parameters on the trajectory of the stance phase curve of the gait cycle have not been previously reported. We hypothesized characteristic changes of age, body height, body weight, body mass index and handgrip strength on the plantar pressure curve trajectory during gait in healthy participants. Thirty-seven healthy women and men with an average age of 43.65 ± 17.59 years were fitted with Moticon OpenGO insoles equipped with 16 pressure sensors each. Data were recorded at a frequency of 100 Hz during walking at 4 km/h on a level treadmill for 1 minute. Data were processed via a custom-made step detection algorithm. The loading and unloading slopes as well as force extrema-based parameters were computed and characteristic correlations with the targeted parameters were identified via multiple linear regression analysis. Age showed a negative correlation with the mean loading slope. Body height correlated with Fmeanload and the loading slope. Body weight and the body mass index correlated with all analyzed parameters, except the loading slope. In addition, handgrip strength correlated with changes in the second half of the stance phase and did not affect the first half, which is likely due to stronger kick-off. However, only up to 46% of the variability can be explained by age, body weight, height, body mass index and hand grip strength. Thus, further factors must affect the trajectory of the gait cycle curve that were not considered in the present analysis. In conclusion, all analyzed measures affect the trajectory of the stance phase curve. When analyzing insole data, it might be useful to correct for the factors that were identified by using the regression coefficients presented in this paper. Keywords: ageing; gait; ground reaction (forces); handgrip strengh; insoles; motion analysis; obesity; smart healthcare. Copyright © 2023 Wolff, Steinheimer, Warmerdam, Dahmen, Slusallek, Schlinkmann, Chen, Orth, Pohlemann and Ganse. Conflict of interest statementTP is president elect and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defense. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 16. | Gait Analysis to Monitor Fracture Healing of the Lower LegBioengineering (Basel). 2023 Feb 15;10(2):255. doi: 10.3390/bioengineering10020255. AuthorsElke Warmerdam 1 , Marcel Orth 2 , Tim Pohlemann 2 , Bergita Ganse 1 2 Affiliations
AbstractFracture healing is typically monitored by infrequent radiographs. Radiographs come at the cost of radiation exposure and reflect fracture healing with a time lag due to delayed fracture mineralization following increases in stiffness. Since union problems frequently occur after fractures, better and timelier methods to monitor the healing process are required. In this review, we provide an overview of the changes in gait parameters following lower leg fractures to investigate whether gait analysis can be used to monitor fracture healing. Studies assessing gait after lower leg fractures that were treated either surgically or conservatively were included. Spatiotemporal gait parameters, kinematics, kinetics, and pedography showed improvements in the gait pattern throughout the healing process of lower leg fractures. Especially gait speed and asymmetry measures have a high potential to monitor fracture healing. Pedographic measurements showed differences in gait between patients with and without union. No literature was available for other gait measures, but it is expected that further parameters reflect progress in bone healing. In conclusion, gait analysis seems to be a valuable tool for monitoring the healing process and predicting the occurrence of non-union of lower leg fractures. Keywords: implant; malunion; motion capture; movement analysis; non-union; rehabilitation; tibial fracture; trauma; wearables. Conflict of interest statementT.P. is president elect and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). T.P. is also the speaker of the medical advisory board of the German Ministry of Defense. The other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The other authors declare no conflict of interest. Full text links |
| 17. | [Management of complications of acetabular fractures]Unfallchirurgie (Heidelb). 2023 Feb;126(2):109-118. doi: 10.1007/s00113-022-01256-y. Epub 2022 Dec 7. [Article in German] AuthorsM Orth 1 , D Osche 2 , T Pohlemann 2 Affiliations
AbstractSurgical treatment of acetabular fractures represents a special challenge in the field of trauma surgery. Complications are mostly due to the trauma itself or are iatrogenic. The handling and strategy to overcome complications in acetabular surgery are oriented towards the type of complication and the time of occurrence. Generally, a differentiation is made between early perioperative complications and late complications. The present article describes the most frequent complications during the surgical treatment of acetabular fractures, discusses the various treatment options based on individual case examples and gives differentiated recommendations to overcome the complications. The treatment concept should initially comprise a comprehensive primary prophylaxis to prevent complications. In cases of early perioperative complications, e.g. postoperative wound infections, hemorrhage or incorrect implant positioning, rapid and systematic surgical revision should be performed. In contrast, the treatment of late complications (e.g. implant associated failures, secondary osteoarthrosis of the hip, periarticular heterotopic ossification, non-unions and late infections) depends on the clinical and functional condition of the patient. In symptomatic elderly patients secondary total hip replacement is usually a valid option, whereas younger patients with late complications can be candidates for joint-preserving procedures. The management of complications in acetabular surgery regularly requires intense patient guidance as well as thorough clarification and should be performed in specialized centers. Die operative Behandlung von Acetabulumfrakturen stellt eine besondere Herausforderung in der Unfallchirurgie dar. Komplikationen sind meist durch den Unfall selbst oder iatrogen bedingt. Der Umgang und die Strategie zur Bewältigung von Komplikationen in der Acetabulumchirurgie richten sich nach der Art und dem Zeitpunkt ihres Auftretens. Generell werden perioperative Frühkomplikationen von Spätkomplikationen unterschieden. Der vorliegende Beitrag stellt die häufigsten Komplikationen in der operativen Behandlung von Acetabulumfrakturen dar, diskutiert die verschiedenen Therapiemöglichkeiten anhand einzelner Fallbeispiele und gibt differenzierte Empfehlungen. Das Versorgungskonzept sollte zunächst eine umfassende Primärprophylaxe zur Vermeidung von Komplikationen umfassen. Eingetretene Frühkomplikationen wie z. B. postoperative Infektionen, Blutungen oder Implantatfehllagen sollten rasch und konsequent im Sinne einer Sekundärprophylaxe chirurgisch behandelt werden. Hingegen richtet sich die Behandlung von Spätkomplikationen (Implantatlockerungen und -brüche, sekundäre Koxarthrose, heterotope Ossifikationen, Pseudarthrosen und Spätinfektionen) nach dem klinischen und funktionellen Beschwerdebild des Patienten. Bei älteren Patienten mit entsprechenden Beschwerden stellt die sekundäre Versorgung mit einer Hüfttotalendoprothese oftmals eine gute Behandlungsmöglichkeit dar, wohingegen bei jüngeren Patienten nach Spätkomplikationen auch gelenkerhaltende Verfahren infrage kommen. Das Management von Komplikationen in der Acetabulumchirurgie erfordert regelhaft eine enge Patientenführung sowie die ausführliche Aufklärung und Beratung der Patienten und sollte in spezialisierten Zentren erfolgen. Keywords: Patient guidance; Pelvis; Perioperative care; Prophylaxis; Total hip arthroplasty. © 2022. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature. |
| 18. | Figure skating: Increasing numbers of revolutions in jumps at the European and World ChampionshipsPLoS One. 2022 Nov 30;17(11):e0265343. doi: 10.1371/journal.pone.0265343. eCollection 2022. AuthorsThomas Rauer 1 , Hans-Christoph Pape 1 , Matthias Knobe 2 , Tim Pohlemann 3 , Bergita Ganse 3 4 Affiliations
AbstractFigure skating is associated with a high prevalence of sport-specific injuries and overuse symptoms. Impacts are of greater magnitude in jumps with more revolutions that are thus connected to a greater risk of injury. While figure skating programs seem to have recently increased in difficulty, performance trends have not yet been reported in the literature. We hypothesized increasing performance and decreasing age trends of the best athletes who competed at international level in recent years. Furthermore, we aimed to identify and analyse objective performance parameters and to assess a potential link between age and the risk of injury. The development of the number of double, triple and quadruple jumps in the singles figure skating events at the World and European Championships since the introduction of the new ISU Judging System in the 2004/2005 season was analysed using regression statistics and Student's T-Tests. In all groups, the numbers of jumps with fewer rotations significantly decreased in the favour of jumps with more rotations. Women only started to perform jumps with four rotations in 2019. In the men, the number of quadruple jumps increased from an average of less than one to more than three in recent years (European and World Championships, both p < 0.001). In the European, but not in the World Championships, the average age increased in the men and decreased in the women (European Championships, men and women p = 0.006). Our study was the first to assess performance trends in elite figure skating. The incidence of injuries and overuse syndromes in figure skating needs to be monitored cautiously, as increases can be expected following recent gains in performance and jump complexity. Copyright: © 2022 Rauer et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Conflict of interest statementThe authors have declared that no competing interests exist. Full text links |
| 19. | Recurring Osteomyelitis Caused by Clostridium celerecrescens in an Adolescent After Motocross Trauma: The Importance of Multidisciplinary CarePediatr Infect Dis J. 2022 Dec 1;41(12):e547-e548. doi: 10.1097/INF.0000000000003687. Epub 2022 Oct 12. AuthorsKatharina Last 1 , Fabian K Berger 1 , Sören L Becker 1 , Cihan Papan 1 , Benedikt J Braun 2 , Philipp Mörsdorf 3 , Tim Pohlemann 3 , Katrin Altmeyer 4 , Arne Simon 5 Affiliations
No abstract available Conflict of interest statementThe authors have no funding or conflicts of interest to disclose. Full text links |
| 20. | Locking Nail versus Plate Fixation in Calcaneal Fractures: Brief report on a Retrospective Analysis of Treatment Characteristics and Radiographic Correction PotentialActa Chir Orthop Traumatol Cech. 2022;89(5):349-352. AuthorsN Stachel 1 , B J Braun 2 , M Orth 3 , S C Herath 2 , M F R Rollmann 2 , M M Menger 2 , T Histing 2 , T Pohlemann 3 Affiliations
AbstractPURPOSE OF THE STUDY Minimal and limited access techniques are gaining increasing interest for the treatment of displaced intra-articular calcaneal fractures. The ideal treatment method is however still debated and largely based on individual case factors and surgeon experience. Aim of this study was thus to compare the treatment characteristics and radiographic correction potential of a locking nail system with a sinus tarsi approach to plate fixation via an extended lateral approach. MATERIAL AND METHODS We retrospectively reviewed 39 cases of patients with calcaneal fractures that received primary fracture treatment for displaced intra-articular calcaneal fractures between July 2017 and March 2020. Patient characteristics, time to surgery, time to discharge, OR time and the correction achieved were analyzed and comparative statistics performed. RESULTS In total 19 patients treated with the locking nail and 20 patients treated with plate fixation were analyzed. Patient age and fracture severity according to the Sanders classification were comparable between the groups. Overall surgical time, as well as the achieved reduction was equal between both groups. Time to surgery, as well as time from surgery to discharge was significantly shorter in the locking nail group. 2 additional soft tissue procedures were necessary in the extended lateral approach group. DISCUSSION AND CONCLUSIONS The results with the locking calcaneus nail and sinus tarsi approach suggest, that similar treatment results can be achieved as with plate osteosynthesis and an extended lateral approach. Soft tissue management, as well as pre- and postoperative timing and discharge management can be improved with the nail. Further controlled trials comparing the longterm outcome between the treatment options are needed. Key words: calcaneus fracture, sinus tarsi approach, calcaneal nail, C-Nail. |
| 21. | Performance Increases in Pair Skating and Ice Dance at International Championships and Olympic GamesInt J Environ Res Public Health. 2022 Sep 19;19(18):11806. doi: 10.3390/ijerph191811806. AuthorsThomas Rauer 1 , Hans-Christoph Pape 1 , Zoé Stehlin 2 , Sandro Heining 1 , Matthias Knobe 3 , Tim Pohlemann 4 , Bergita Ganse 4 5 Affiliations
AbstractIn pair skating and ice dance, performance seems to have increased at international competitions, which is potentially associated with changes in athlete age. We hypothesized increasing age, numbers of total points and more complex jumps of the best elite couples at international championships in recent years. Corresponding data were assessed via the results databases of the European and World Championships, as well as the Winter Olympics since 2005. Linear regression statistics were conducted, and significance was assessed via one-way ANOVAs. There were no significant changes in age. Increases in total points were found in both disciplines (World and European Championships both p < 0.001 for both disciplines, Olympics pair skating p = 0.003, ice dance n/a). Significant increases were found in the number of double and triple twist jumps at the European Championships (Double p = 0.046, triple p = 0.041), but not at the World Championships or the Olympics. At the World Championships, single solo jumps decreased (p = 0.031) in favor of triple jumps, which increased (p = 0.020), without a similar effect at the European Championships or Olympics. In conclusion, increases in total points and more complex jumps were observed at international championships without associated changes in age. Attention should be given to possible changes in the incidence of acute and overuse injuries following this development. Keywords: age; competition; elite athlete; figure skating; performance; trauma; winter sports. Conflict of interest statementThe authors declare no conflict of interest. Full text links |
| 22. | Minimal-invasive anterior approach to the hip provides a better surgery-related and early postoperative functional outcome than conventional lateral approach after hip hemiarthroplasty following femoral neck fracturesArch Orthop Trauma Surg. 2023 Jun;143(6):3173-3181. doi: 10.1007/s00402-022-04602-2. Epub 2022 Sep 2. AuthorsM Orth 1 , D Osche 2 , P Mörsdorf 2 , J H Holstein 2 3 , M F Rollmann 2 4 , T Fritz 2 , T Pohlemann 2 , A Pizanis 2 Affiliations
AbstractIntroduction: Femoral neck fractures (FNF) are one of the most frequent fractures among elderly patients and commonly require surgical treatment. Bipolar hip hemiarthroplasty (BHHA) is mostly performed in these cases. Material and methods: In the present retrospective study geriatric patients with FNF (n = 100) treated either by anterior minimal-invasive surgery (AMIS; n = 50) or lateral conventional surgery (LCS; n = 50) were characterized (age at the time of surgery, sex, health status/ASA score, walking distance and need for walking aids before the injury) and intraoperative parameters (duration of surgery, blood loss, complications), as well as postoperative functional performance early (duration of in-patient stay, radiological leg length discrepancy, ability to full weight-bearing, mobilization with walking aids) and 12 months (radiological signs of sintering, clinical parameters, complication rate) after surgery were analyzed. Results: Patients in the AMIS group demonstrated a reduced blood loss intraoperatively, while the duration of surgery and complication rates did not differ between the two groups. Further, more patients in the AMIS group achieved full weight-bearing of the injured leg and were able to walk with a rollator or less support during their in-patient stay. Of interest, patients in the AMIS group achieved this level of mobility earlier than those of the LCS group, although their walking distance before the acute injury was reduced. Moreover, patients of the AMIS group showed equal leg lengths postoperatively more often than patients of the LCS group. No significant differences in functional and surgery-related performance could be observed between AMIS and LCS group at 12 months postoperatively. Conclusions: In conclusion, geriatric patients treated by AMIS experience less surgery-related strain and recover faster in the early postoperative phase compared to LCS after displaced FNF. Hence, AMIS should be recommended for BHHA in these vulnerable patients. Keywords: AMIS; Femoral neck fracture; Hemiarthroplasty; Hip; Lateral approach. © 2022. The Author(s). Conflict of interest statementThe authors have no relevant financial or non-financial interests to disclose. Full text links |
| 23. | Sacroiliac Screw Placement with Ease: CT-Guided Pelvic Fracture Osteosynthesis in the ElderlyMedicina (Kaunas). 2022 Jun 15;58(6):809. doi: 10.3390/medicina58060809. AuthorsHannah Kress 1 , Roman Klein 1 , Tim Pohlemann 2 , Christoph Georg Wölfl 1 Affiliations
AbstractBackground and Objectives: The number of geriatric patients presenting with fragility fractures of the pelvis is increasing due to ageing Western societies. There are nonoperative and several operative treatment approaches. Many of which cause prolonged hospitalisation, so patients become bedridden and lose mobility and independence. This retrospective study evaluates the postoperative outcome of a computed tomography-guided (CT-guided) minimally invasive approach of sacroiliac screw osteosynthesis. The particular focus is to demonstrate its ease of use, feasibility with the equipment of virtually every hospital and beneficial outcomes to the patients. Materials and Methods: 28 patients (3 men, 25 women, age 80.5 ± 6.54 years) with fragility fractures of the pelvis types II-IV presenting between August 2015 and September 2021 were retrospectively reviewed. The operation was performed using the CT of the radiology department for intraoperative visualization of screw placement. Patients only received screw osteosynthesis of the posterior pelvic ring and cannulated screws underwent cement augmentation. Outcomes measured included demographic data, fracture type, postoperative parameters and complications encountered. The quality of life (QoL) was assessed using the German version of the EQ-5D-3L. Results: The average operation time was 32.4 ± 9.6 min for the unilateral and 50.7 ± 17.4 for the bilateral procedure. There was no significant difference between surgeons operating (p = 0.12). The postoperative CT scans were used to evaluate the outcome and showed only one case of penetration (by 1 mm) of the ventral cortex, which did not require operative revision. No case of major complication was reported. Following surgery, patients were discharged after a median of 4 days (Interquartile range 3-7.5). 53.4% of the patients were discharged home or to rehabilitation. The average score on the visual analogue scale of the EQ-5D-3L evaluating the overall wellbeing was 55.6 (Interquartile range (IQR) 0-60). Conclusions: This study shows that the operative method is safe to use in daily practice, is readily available and causes few complications. It permits immediate postoperative mobilization and adequate pain control. Independence and good quality of life are preserved. Keywords: fracture; osteoporosis; pelvis; spine. Conflict of interest statementThe authors declare no conflict of interest. Full text links |
| 24. | Dose-dependent dominance: How cell densities design stromal cell functions during soft tissue healingCell Biochem Funct. 2022 Jul;40(5):439-450. doi: 10.1002/cbf.3705. Epub 2022 Jun 15. AuthorsPhilipp Kuhn 1 , Monika Bubel 1 , Martina Jennewein 1 , Silke Guthörl 1 , Tim Pohlemann 1 , Martin Oberringer 1 Affiliation
AbstractRegular soft tissue healing relies on the well-organized interaction of different stromal cell types with endothelial cells. However, spatiotemporal conditions might provoke high densities of one special stromal cell type, potentially leading to impaired healing. Detailed knowledge of the functions of rivaling stromal cell types aiming for tissue contraction and stabilization as well as vascular support is mandatory. By the application of an in vitro approach comprising the evaluation of cell proliferation, cell morphology, myofibroblastoid differentiation, and cytokine release, we verified a density-dependent modulation of these functions among juvenile and adult fibroblasts, pericytes, and adipose-derived stem cells during their interaction with microvascular endothelial cells in cocultures. Results indicate that juvenile fibroblasts rather support angiogenesis via paracrine regulation at the early stage of healing, a role potentially compromised in adult fibroblasts. In contrast, pericytes showed a more versatile character aiming at angiogenesis, vessel stabilization, and tissue contraction. Such a universal character was even more pronounced among adipose-derived stem cells. The explicit knowledge of the characteristic functions of stromal cell types is a prerequisite for the development of new analytical and therapeutic approaches for impaired soft tissue healing. The present study delivers new considerations concerning the roles of rivaling stromal cell types within a granulation tissue, pointing to extraordinary properties of pericytes and adipose-derived stem cells. Keywords: adipose-derived stem cell; endothelial cell; fibroblast; pericyte; stromal cell; tissue repair; wound healing. © 2022 The Authors. Cell Biochemistry and Function published by John Wiley & Sons Ltd. Full text links |
| 25. | Weight-Bearing Restrictions after Acetabular Fracture, Necessity or False Hope? A Brief Observational StudyActa Chir Orthop Traumatol Cech. 2022;89(2):146-149. AuthorsB J Braun 1 , T Histing 1 , M F R Rollmann 1 , M M Menger 1 , D Osche 2 , M Orth 2 , T Pohlemann 2 , S C Herath 1 Affiliations
AbstractPURPOSE OF THE STUDY Most common postoperative treatment recommendations after acetabulum fractures suggest at least 6 weeks of postoperative partial or non weight-bearing. To protect the osteosynthetic construct this surgically set weight-bearing limit is trained by physical therapy. Aim of our analysis was to determine the free field patient compliance to these weight-bearing restrictions and observe their influence on the early postoperative radiographic imaging. MATERIAL AND METHODS Patients after surgical treatment of an acetabulum fracture were included in our analysis. Every patient was instructed to maintain a 20 kg weight-bearing limit for 6 weeks. Postoperative weight-bearing was continuously monitored during this time with a pressure measuring insole. Maximum weight-bearing per day was recorded and maintenance of reduction assessed after this time. RESULTS In total 10 patients were included into the study. Only 1 patient stayed within the weight-bearing limit during the analysis. Maximum weight-bearing as high as 110 kg was recorded. All patients maintained postoperative reduction at the 6 week timepoint. DISCUSSION AND CONCLUSIONS Despite regular physical therapy training compliance to the generally accepted weight-bearing limits was low. Regardless of the non-compliance the radiographic outcome remained unchanged. Further analysis on the use of permissive weightbearing aftercare regimes are warranted. Key words: weight-bearing, acetabulum fracture, compliance. |
| 26. | Concepts and clinical aspects of active implants for the treatment of bone fracturesActa Biomater. 2022 Jul 1:146:1-9. doi: 10.1016/j.actbio.2022.05.001. Epub 2022 May 7. AuthorsBergita Ganse 1 , Marcel Orth 2 , Michael Roland 3 , Stefan Diebels 3 , Paul Motzki 4 , Stefan Seelecke 4 , Susanne-Marie Kirsch 4 , Felix Welsch 4 , Annchristin Andres 3 , Kerstin Wickert 3 , Benedikt J Braun 5 , Tim Pohlemann 2 Affiliations
Free article AbstractNonunion is a complication of long bone fractures that leads to disability, morbidity and high costs. Early detection is difficult and treatment through external stimulation and revision surgery is often a lengthy process. Therefore, alternative diagnostic and therapeutic options are currently being explored, including the use of external and internal sensors. Apart from monitoring fracture stiffness and displacement directly at the fracture site, it would be desirable if an implant could also vary its stiffness and apply an intervention to promote healing, if needed. This could be achieved either by a predetermined protocol, by remote control, or even by processing data and triggering the intervention itself (self-regulated 'intelligent' or 'smart' implant). So-called active or smart materials like shape memory alloys (SMA) have opened up opportunities to build active implants. For example, implants could stimulate fracture healing by active shortening and lengthening via SMA actuator wires; by emitting pulses, waves, or electromagnetic fields. However, it remains undefined which modes of application, forces, frequencies, force directions, time durations and periods, or other stimuli such implants should ideally deliver for the best result. The present paper reviews the literature on active implants and interventions for nonunion, discusses possible mechanisms of active implants and points out where further research and development are needed to build an active implant that applies the most ideal intervention. STATEMENT OF SIGNIFICANCE: Early detection of delays during fracture healing and timely intervention are difficult due to limitations of the current diagnostic strategies. New diagnostic options are under evaluation, including the use of external and internal sensors. In addition, it would be desirable if an implant could actively facilitate healing ('Intelligent' or 'smart' implant). Implants could stimulate fracture healing via active shortening and lengthening; by emitting pulses, waves, or electromagnetic fields. No such implants exist to date, but new composite materials and alloys have opened up opportunities to build such active implants, and several groups across the globe are currently working on their development. The present paper is the first review on this topic to date. Keywords: Fracture healing; Shape memory alloy; Smart implant; Surgery; Trauma. Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved. Conflict of interest statementDeclaration of Competing Interest TP is president elect and board member of the AO Foundation, Switzerland, and extended board member of the German Society of Orthopedic Trauma Surgery (DGU), the German Society of Orthopedic Surgery and Traumatology (DGOU), and the German Society of Surgery (DGCH). TP is also the speaker of the medical advisory board of the German Ministry of Defense. The other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Full text links |
| 27. | Development of an ischemic fracture healing model in miceActa Orthop. 2022 Apr 25:93:466-471. doi: 10.2340/17453674.2022.2529. AuthorsMaximilian M Menger 1 , Janine Stutz 2 , Sabrina Ehnert 3 , Andreas K Nussler 4 , Mika F Rollmann 5 , Steven C Herath 6 , Benedikt J Braun 7 , Tim Pohlemann 8 , Michael D Menger 9 , Tina Histing 10 Affiliations
AbstractBackground and purpose: In fracture healing, ischemia caused by vascular injuries, chronic vascular diseases, and metabolic comorbidities is one of the major risk factors for delayed union and non-union formation. To gain novel insights into the molecular and cellular pathology of ischemic fracture healing, appropriate animal models are needed. Murine models are of particular interest, as they allow to study the molecular aspects of fracture healing due to the availability of both a large number of murine antibodies and gene-targeted animals. Thus, we present the development of an ischemic fracture healing model in mice. Material and methods: After inducing a mild ischemia by double ligature of the deep femoral artery in CD-1 mice, the ipsilateral femur was fractured by a 3-point bending device and stabilized by screw osteosynthesis. In control animals, the femur was fractured and stabilized without the induction of ischemia. The femora were analyzed at 2 and 5 weeks after fracture healing by means of radiology, biomechanics, histology, and histomorphometry. Results: The surgically induced ischemia delayed and impaired the process of fracture healing. This was indicated by a lower Goldberg score, decreased bending stiffness, and reduced bone callus formation in the ischemic animals when compared with the controls. Interpretation: We introduce a novel ischemic femoral fracture healing model in mice, which is characterized by delayed bone healing. In future, the use of this model may allow both the elucidation of the molecular aspects of ischemic fracture healing and the study of novel treatment strategies. Full text links |
| 28. | COVID-19: a catalyst for the digitization of surgical teaching at a German University HospitalBMC Med Educ. 2022 Apr 22;22(1):308. doi: 10.1186/s12909-022-03362-2. AuthorsMilan Anton Wolf 1 2 , Antonius Pizanis 3 , Gerrit Fischer 4 , Frank Langer 5 , Philipp Scherber 6 , Janine Stutz 3 , Marcel Orth 3 , Tim Pohlemann 3 , Tobias Fritz 3 Affiliations
AbstractBackground: The summer semester 2020, had to be restructured due to the SARS-CoV-2 pandemic and the associated contact restrictions. Here, for the first time, the established lectures in lecture halls and small group seminars could not be conducted in presence as usual. A possible tool for the implementation of medical teaching, offers the use of eLearning, online webinars and learning platforms. At present it is unclear how the SARS-CoV-2 pandemic will affect surgical teaching, how digitization will be accepted by students, and how virtual teaching can be expanded in the future. Methods: The teaching, which was previously delivered purely through face-to-face lectures, was completely converted to digital media. For this purpose, all lectures were recorded and were available to students on demand. The seminars were held as a twice a week occurring online webinar. The block internship was also conducted as a daily online webinar and concluded with an online exam at the end. At the end of the semester, a survey of the students was carried out, which was answered by n = 192 students with an anonymized questionnaire. The questionnaire inquires about the previous and current experience with eLearning, as well as the possibility of a further development towards a purely digital university. Results: There were n = 192 students in the study population. For 88%, the conversion of classes to web-based lectures represented their first eLearning experience. For 77% of all students, the digitization of teaching led to a change in the way they prepare for class. 73% of the participating students are of the opinion that eLearning lectures should continue to be offered. 54% of the students felt that eLearning lectures made more sense than face-to-face lectures. A purely virtual university could be imagined by 41% of the students. Conclusion: The conversion of teaching represented the first contact with eLearning for most students. Overall, the eLearning offering was experienced as positive. Due to the new teaching structure, the way of learning had already changed during the semester. Based on the new eLearning content, the already existing formats can be further expanded in the future. Nevertheless, it turned out that the practical-surgical contents and skills cannot be adequately represented by purely online offers; for this, the development of hybrid practice-oriented teaching concepts is necessary. Keywords: Covid-19; Digitalization; Surgical education; Webinar; eLearning. © 2022. The Author(s). Conflict of interest statementThe authors declare that they have no competing interests. Full text links |
| 29. | Experiences in the Use of Motorized Intramedullary Nails after Complex Injuries to the ExtremitiesZ Orthop Unfall. 2023 Jun;161(3):271-279. doi: 10.1055/a-1640-0935. Epub 2022 Feb 1. [Article in English, German] AuthorsMarcel Orth 1 , Philipp Mörsdorf 1 , Tobias Fritz 1 , Benedikt J Braun 2 , Vakhtang Pirpilashvili 1 , Janine Stutz 1 , Nils Veith 1 , Tim Pohlemann 1 , Antonius Pizanis 1 Affiliations
AbstractThe treatment of complex injuries of the extremities after comminuted fractures or non-unions is a challenging area in the field of trauma surgery. Internal, motorized implants nowadays enable a patient-oriented and progressive treatment of these cases. The present article aims to present modern treatment strategies of complex injuries of the extremities, support the use of novel, motorized intramedullary nails and provide experiences for the handling with lengthening nails or transport nails. For this purpose, the preoperative planning including selection of patients, presentation of internal lengthening and transport systems and the most important factors during preparation of the surgery are described. Moreover, critical steps during the implantation of motorized nails and also during potential follow-up interventions are highlighted and the postoperative protocol including precise recommendations for the transport und consolidation phase are provided. Finally, the experiences are illustrated by presentation of the four different cases. The use of internal, motorized implants represents the latest step in the treatment of complex injuries of the extremities. These implants improve the quality of life and the authors recommend its use. However, these implants require a high expertise and adaption of established treatment protocols in these challenging trauma cases. Follow-up analyses with a considerably large number of cases are necessary and the research on implants to solve persisting problems in the area of complex injuries of the extremities has to be pursued intensively. Die Behandlung komplexer Extremitätenverletzungen infolge von Trümmerfrakturen oder Pseudarthrosen stellt eine besondere Herausforderung in der Unfallchirurgie dar. Rein interne, motorisierte Implantatsysteme ermöglichen heutzutage eine patientenorientierte und fortschrittliche Behandlung solcher Fälle. Der vorliegende Beitrag soll moderne Behandlungskonzepte komplexer Extremitätenverletzungen vorstellen, Unterstützung bei der Anwendung neuartiger, motorisierter Marknägel liefern und Erfahrungen beim Umgang mit Verlängerungs- und Transportnägeln darstellen. Hierzu wird zunächst die präoperative Planung inkl. Patientenselektion, Vorstellung interner Verlängerungs- und Transportsysteme und der wichtigsten Faktoren für die OP-Vorbereitung erläutert. Im Anschluss werden intraoperative Besonderheiten bei der Implantation motorisierter Marknägel sowie bei möglichen Folgeeingriffen dargestellt und das postoperative Prozedere mit konkreten Empfehlungen zur Transport- und Konsolidierungsphase beschrieben. Abschließend werden die Erfahrungen durch 4 Anwendungsbeispiele veranschaulicht. Der Einsatz interner, motorisierter Implantate stellt den derzeit letzten Schritt in der Behandlung komplexer Extremitätenverletzungen dar. Sie verbessern die Lebensqualität betroffener Patienten und ihre Anwendung wird seitens der Autoren befürwortet. Doch erfordern diese neuen Implantate ein hohes Maß an Expertise und eine Anpassung etablierter Behandlungsstrategien bei diesen ohnehin anspruchsvollen unfallchirurgischen Krankheitsbildern. Weitere Untersuchungen mit großen Fallzahlen sollten künftig erhoben und die Implantatforschung zur Lösung fortbestehender Probleme in der Behandlung komplexer Extremitätenverletzungen intensiv fortgesetzt werden. Thieme. All rights reserved. Conflict of interest statementDie Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht. Full text links |
| 30. | Local Application of Mineral-Coated Microparticles Loaded With VEGF and BMP-2 Induces the Healing of Murine Atrophic Non-UnionsFront Bioeng Biotechnol. 2022 Jan 11:9:809397. doi: 10.3389/fbioe.2021.809397. eCollection 2021. AuthorsM Orth 1 2 , T Fritz 1 , J Stutz 1 2 , C Scheuer 2 , B Ganse 1 3 , Y Bullinger 1 , J S Lee 4 , W L Murphy 4 , M W Laschke 2 , M D Menger 2 , T Pohlemann 1 Affiliations
AbstractDeficient angiogenesis and disturbed osteogenesis are key factors for the development of nonunions. Mineral-coated microparticles (MCM) represent a sophisticated carrier system for the delivery of vascular endothelial growth factor (VEGF) and bone morphogenetic protein (BMP)-2. In this study, we investigated whether a combination of VEGF- and BMP-2-loaded MCM (MCM + VB) with a ratio of 1:2 improves bone repair in non-unions. For this purpose, we applied MCM + VB or unloaded MCM in a murine non-union model and studied the process of bone healing by means of radiological, biomechanical, histomorphometric, immunohistochemical and Western blot techniques after 14 and 70 days. MCM-free non-unions served as controls. Bone defects treated with MCM + VB exhibited osseous bridging, an improved biomechanical stiffness, an increased bone volume within the callus including ongoing mineralization, increased vascularization, and a histologically larger total periosteal callus area consisting predominantly of osseous tissue when compared to defects of the other groups. Western blot analyses on day 14 revealed a higher expression of osteoprotegerin (OPG) and vice versa reduced expression of receptor activator of NF-κB ligand (RANKL) in bone defects treated with MCM + VB. On day 70, these defects exhibited an increased expression of erythropoietin (EPO), EPO-receptor and BMP-4. These findings indicate that the use of MCM for spatiotemporal controlled delivery of VEGF and BMP-2 shows great potential to improve bone healing in atrophic non-unions by promoting angiogenesis and osteogenesis as well as reducing early osteoclast activity. Keywords: BMP-2; VEGF; bone healing; fracture; mineral-coated microparticles; non-union. Copyright © 2022 Orth, Fritz, Stutz, Scheuer, Ganse, Bullinger, Lee, Murphy, Laschke, Menger and Pohlemann. Conflict of interest statementThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 31. | Individualized Determination of the Mechanical Fracture Environment After Tibial Exchange Nailing-A Simulation-Based Feasibility StudyFront Surg. 2021 Sep 29:8:749209. doi: 10.3389/fsurg.2021.749209. eCollection 2021. AuthorsBenedikt J Braun 1 , Marcel Orth 2 , Stefan Diebels 3 , Kerstin Wickert 3 , Annchristin Andres 3 , Joshua Gawlitza 4 , Arno Bücker 5 , Tim Pohlemann 2 , Michael Roland 3 Affiliations
AbstractNon-union rate after tibial fractures remains high. Apart from largely uncontrollable biologic, injury, and patient-specific factors, the mechanical fracture environment is a key determinant of healing. Our aim was to establish a patient-specific simulation workflow to determine the mechanical fracture environment and allow for an estimation of its healing potential. In a referred patient with failed nail-osteosynthesis after tibial-shaft fracture exchange nailing was performed. Post-operative CT-scans were used to construct a three-dimensional model of the treatment situation in an image processing and computer-aided design system. Resulting forces, computed in a simulation-driven workflow based on patient monitoring and motion capturing were used to simulate the mechanical fracture environment before and after exchange nailing. Implant stresses for the initial and revision situation, as well as interfragmentary movement, resulting hydrostatic, and octahedral shear strain were calculated and compared to the clinical course. The simulation model was able to adequately predict hardware stresses in the initial situation where mechanical implant failure occurred. Furthermore, hydrostatic and octahedral shear strain of the revision situation were calculated to be within published healing boundaries-accordingly the fracture healed uneventfully. Our workflow is able to determine the mechanical environment of a fracture fixation, calculate implant stresses, interfragmentary movement, and the resulting strain. Critical mechanical boundary conditions for fracture healing can be determined in relation to individual loading parameters. Based on this individualized treatment recommendations during the early post-operative phase in lower leg fractures are possible in order to prevent implant failure and non-union development. Keywords: fracture healing; individualized simulation; non-union; simulation; tibia. Copyright © 2021 Braun, Orth, Diebels, Wickert, Andres, Gawlitza, Bücker, Pohlemann and Roland. Conflict of interest statementThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 32. | Acceleration of Longitudinal Track and Field Performance Declines in Athletes Who Still Compete at the Age of 100 YearsFront Physiol. 2021 Sep 28:12:730995. doi: 10.3389/fphys.2021.730995. eCollection 2021. AuthorsBergita Ganse 1 2 , Anne Kristin Braczynski 3 4 , Christoph Hoog Antink 5 , Matthias Knobe 6 , Tim Pohlemann 2 , Hans Degens 7 8 Affiliations
AbstractWhile physical performance decline rates accelerate after around the age of 70 years, longitudinal athletic performance trends in athletes older than 95 years are unknown. We hypothesized a further accelerated decline in human performance in athletes who still perform at the age of 100 years. To investigate this, longitudinal data of all athletes with results at or over the age of 100 years were collected from the "World Master Rankings" data base spanning 2006-2019 (138 results from 42 athletes; 5 women, 37 men; maximum 105 years) and compared to previously published longitudinal data from 80- to 96-year-old athletes from Sweden (1,134 results from 374 athletes). Regression statistics were used to compare performance decline rates between disciplines and age groups. On average, the individual decline rate of the centenarian group was 2.53 times as steep (100 m: 8.22x; long jump: 0.82x; shot put: 1.61x; discus throw: 1.04x; javelin throw: 0.98x) as that seen in non-centenarians. The steepest increase in decline was found in the 100-m sprint (t-test: p < 0.05, no sign. difference in the other disciplines). The pooled regression statistics of the centenarians are: 100 m: R = 0.57, p = 0.004; long jump: R = 0.90, p < 0.001; shot put: R = 0.65, p < 0.001; discus throw: R = 0.73, p < 0.001; javelin throw: R = 0.68, p < 0.001. This first longitudinal dataset of performance decline rates of athletes who still compete at 100 years and older in five athletics disciplines shows that there is no performance plateau after the age of 90, but rather a further acceleration of the performance decline. Keywords: aging; centenarian; javelin throw; long jump; longevity; master athletics; oldest-old; physical activity. Copyright © 2021 Ganse, Braczynski, Hoog Antink, Knobe, Pohlemann and Degens. Conflict of interest statementThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Full text links |
| 33. | The effect of an infra-acetabular screw for anatomically shaped three-dimensional plate or standard plate designs in acetabulum fractures: a biomechanical analysisEur J Trauma Emerg Surg. 2022 Oct;48(5):3757-3764. doi: 10.1007/s00068-021-01805-x. Epub 2021 Oct 7. AuthorsI Graul 1 2 , I Marintschev 1 , A Pizanis 3 , S C Herath 3 4 , T Pohlemann 3 , T Fritz 5 Affiliations
AbstractBackground: Various plate shapes and implant configurations are used for stabilization of acetabulum fractures via anterior approaches. Little is known about the biomechanical stability of a two-dimensionally shaped "conventional" plate ("J-Plate"-JP) in comparison to three-dimensionally shaped plate configurations (3DP). In addition, the augmentary effect of an infra-acetabular lag-screw (IACS) fixation for anterior column and posterior hemi-transverse acetabulum fractures has not been clarified in comparison of JP and 3DP constructs. This study analyzed the difference between the biomechanical stability of JP compared to 3DP and the role of an IACS in a standardized acetabular fracture model in a single-leg stance loading configuration. Methods: In an artificial bone substitute pelvis model (Synbone© Malans, Switzerland), a typical and standardized fracture pattern (anterior column and posterior hemi-transverse) was created with osteotomy jigs. After anatomic reduction the stabilization was performed using JP or 3DP. Eight pelvises per group were axially loaded in a single-leg stance model up to 400 N. After the load cycle, an additional infra-acetabular screw was placed and the measurement repeated. Fragment displacement was recorded by an optical tracking system (Optitrack Prime 13®, Corvallis, USA). Results: In the pure placement, 3DP provided significantly superior stability when compared to JP. Augmentation of JP by IACS increased the stability significantly, up to the level of 3DP alone, whereas augmentation of the 3DP did not result in further increase of overall stability. Conclusion: The anatomically shaped plate alone provides a superior biomechanical stability in fixation of an anterior column and posterior hemi-transverse fracture model. In a JP fixation the augmentation by IACS provides similar strength as the anatomically shaped 3DP. By use of the anatomically shaped 3DP the need of a clinically risky application of IACS might be avoidable. Level of evidence: IV, Experimental study. Keywords: Acetabular fracture; Anatomically shaped plate; Biomechanics; Infra-acetabular screw; Suprapectineal. © 2021. The Author(s). Conflict of interest statementThe authors state no conflict of interest for this study. Full text links |
| 34. | Macrophage-activating lipoprotein (MALP)-2 impairs the healing of partial tendon injuries in miceAnn Anat. 2022 Jan:239:151818. doi: 10.1016/j.aanat.2021.151818. Epub 2021 Aug 13. AuthorsTobias Fritz 1 , Julia Schäfer 2 , Claudia Scheuer 3 , Janine Stutz 2 , Tina Histing 4 , Tim Pohlemann 2 , Michael D Menger 3 , Matthias W Laschke 3 , Moritz Klein 2 , Marcel Orth 2 Affiliations
AbstractTendon injuries are accounted for up to 50% of musculoskeletal injuries and often result in poor outcomes. Inflammation is a major hallmark of tendon regeneration. Therefore, we analyzed in this study whether the topical application of the pro-inflammatory mediator macrophage-activating lipoprotein (MALP)-2 improves the healing of partial tendon injuries. C57BL/6 mice underwent a partial tenotomy of the flexor digitorum longus tendon of the left hind limb, which was treated with a solution containing either 0.5 µg MALP-2 or vehicle (control). Repetitive gait analyses were performed prior to the surgical intervention as well as postoperatively on days 1, 3, 7, 14 and 36. The structural stability of the tendons was biomechanically tested on day 7 and 36. In addition, Western blot analyses were performed on isolated tendons that were treated in vitro with MALP-2 or vehicle. In both groups, partial tenotomy resulted in a pathological gait pattern during the initial postoperative phase. On day 7, the gait pattern normalized in vehicle-treated animals, but not in MALP-2-treated mice. Moreover, the tendons of MALP-2-treated mice exhibited a significantly reduced biomechanical stiffness after 7 and 36 days when compared to controls. Western blot analyses revealed a significantly higher expression of heme oxygenase (HO)-1 and lower expression of cyclin D in MALP-2-treated tendons. These findings indicate that MALP-2 delays the healing of injured tendons most likely due to increased intracellular stress and suppressed cell proliferation in this naturally bradytrophic tissue. Hence, the application of MALP-2 cannot be recommended for the treatment of tendon injuries. Keywords: Catwalk XT; Gait analysis; Inflammation; MALP-2; Tendon healing; Tendon injury. Copyright © 2021 Elsevier GmbH. All rights reserved. Conflict of interest statementConflict of interest All authors declare no conflict of interest. Full text links |
| 35. | [Case-based learning can improve the teaching quality in trauma surgery education : A survey analysis among medical students]Unfallchirurg. 2022 Mar;125(3):219-226. doi: 10.1007/s00113-021-01009-3. Epub 2021 Jun 8. [Article in German] AuthorsFriedemann Strobel 1 2 , Tina Histing 1 , Tim Pohlemann 1 , Antonius Pizanis 1 , Benedikt Johannes Braun 1 , Marcel Orth 1 , Tobias Fritz 3 Affiliations
AbstractBackground: Medical education has always been challenging for students and teachers. Of growing importance is the promotion of knowledge of correlations and knowledge transfer from theoretical aspects into clinical practice. In order to achieve this aim, student-centered teaching concepts are increasingly being employed in the literature. Objective: Can a trauma surgery practical seminar be improved by a case-based teaching concept? Material and methods: For this purpose, standardized case studies and corresponding teaching materials, such as classification aids and treatment strategies, were made available to the students and lecturers. Using a two-staged evaluation the effects of the modified teaching design could be recorded and statistically analyzed. Results: The seminar was considered to be relevant for the examinations. The teaching by the lecturers was found to be more competent and appeared more motivated. Overall, the seminar was rated better by the students. Conclusion: A case-based teaching concept can significantly improve the education in trauma surgery, when correctly and specifically implemented. Zusammenfassung: HINTERGRUND: Medizinische Lehre ist seit jeher eine Herausforderung für Studierende und Dozenten. Die Förderung des Zusammenhangswissens und ein Wissenstransfer von der Theorie auf die Praxis gewinnen in den letzten Jahren an Bedeutung. Um dieses Ziel zu erreichen, werden zunehmend studierendenzentrierte Lehrkonzepte in der Literatur eingesetzt. Fragestellung: Kann durch ein fallbasiertes Lehrkonzept das unfallchirurgische Seminar verbessert werden? Material und methoden: Den Studierenden und Dozenten wurden standardisierte Fallbeispiele und dazugehörige Unterrichtsmaterialien wie Klassifikationshilfen und Versorgungsstrategien zur Verfügung gestellt. Durch eine zweizeitige Evaluation konnten die Auswirkungen dieser Modifikationen des Lehrdesigns erfasst und statistisch ausgewertet werden. Ergebnisse: Das Seminar wurde als prüfungsrelevanter empfunden. Die Lehre durch die Dozenten wurde als kompetenter und motivierter empfunden. Insgesamt wurde das Seminar durch die Studierenden besser bewertet. Schlussfolgerungen: Ein fallbasiertes Lehrkonzept kann daher, richtig und gezielt eingesetzt, die unfallchirurgische Lehre signifikant verbessern. Keywords: Case-based learning; Student-centered teaching format; Surgical teaching; Teaching; Trauma surgery seminar. © 2021. The Author(s). Full text links |
| 36. | Amlodipine accelerates bone healing in a stable closed femoral fracture model in miceEur Cell Mater. 2021 May 24:41:592-602. doi: 10.22203/eCM.v041a38. AuthorsM M Menger 1 , B Merscher, C Scheuer, B J Braun, S C Herath, M F Rollmann, D Stenger, T Später, T Pohlemann, M D Menger, T Histing Affiliation
Free article AbstractCalcium channel blockers (CCBs), which are widely used in the treatment of hypertension, have been shown to influence bone metabolism. However, there is little information on whether CCBs also influence the process of fracture healing. Therefore, the effect of the CCB amlodipine on bone healing was studied in a stable closed fracture model in mice using intramedullary screw fixation. Bone healing was investigated by radiology, biomechanics, histomorphometry and Western blot analysis 2 and 5 weeks after fracture healing. Animals were treated daily (post operatively) per os using a gavage with amlodipine low dose (1 mg/ kg body weight, n = 20), amlodipine high dose (3 mg/kg body weight, n = 20) or vehicle (NaCl) (control, n = 20) serving as a negative control. At 2 and 5 weeks, histomorphometric analysis revealed a significantly larger amount of bone tissue within the callus of amlodipine low-dose- and high-dose-treated animals when compared to controls. This was associated with a smaller amount of cartilaginous and fibrous tissue, indicating an acceleration of fracture healing. Biomechanics showed a slightly, but not significantly, higher bending stiffness in amlodipine low-dose- and high-dose-treated animals. Western blot analysis revealed a significantly increased expression of bone morphogenetic protein (BMP)-2 and vascular endothelial growth factor (VEGF). Moreover, the analysis showed a 5-fold higher expression of osteoprotegerin (OPG) and a 10-fold elevated expression of the receptor activator of NF-κB ligand (RANKL), indicating an increased bone turnover. These findings demonstrated that amlodipine accelerated fracture healing by stimulating bone formation, callus remodelling and osteoclast activity. Full text links |
| 37. | Flow cytometric quantification of apoptotic and proliferating cells applying an improved method for dissociation of spheroidsCell Biol Int. 2021 Aug;45(8):1633-1643. doi: 10.1002/cbin.11618. Epub 2021 May 11. AuthorsWolfgang Metzger 1 , Barbara Rösch 1 , Daniela Sossong 1 , Monika Bubel 1 , Tim Pohlemann 1 Affiliation
AbstractSpheroids are a promising tool for many cell culture applications, but their microscopic analysis is limited. Flow cytometry on a single cell basis, which requires a gentle but also efficient dissociation of spheroids, could be an alternative analysis. Mono-culture and coculture spheroids consisting of human fibroblasts and human endothelial cells were generated by the liquid overlay technique and were dissociated using AccuMax as a dissociation agent combined with gentle mechanical forces. This study aimed to quantify the number of apoptotic and proliferative cells. We were able to dissociate spheroids of differing size, age, and cellular composition in a single-step dissociation protocol within 10 min. The number of single cells was higher than 95% and in most cases, the viability of the cells after dissociation was higher than 85%. Coculture spheroids exhibited a higher sensitivity as shown by lower viability, higher amount of cellular debris, and a higher amount of apoptotic cells. Considerable expression of the proliferation marker Ki67 could only be seen in 1-day-old spheroids but was already downregulated on Day 3. In summary, our dissociation protocol enabled a fast and gentle dissociation of spheroids for the subsequent flow cytometric analysis. The chosen cell type had a strong influence on cell viability and apoptosis. Initially high rates of proliferative cells decreased rapidly and reached values of healthy tissue 3 days after generation of the spheroids. In conclusion, the flow cytometry of dissociated spheroids could be a promising analytical tool, which could be ideally combined with microscopic techniques. Keywords: Ki67; activated caspase 3; dissociation; flow cytometry; live-dead-assay; spheroids. © 2021 The Authors. Cell Biology International published by John Wiley & Sons Ltd on behalf of International Federation of Cell Biology. Full text links |
| 38. | Clinical feasibility of fracture healing assessment through continuous monitoring of implant loadJ Biomech. 2021 Feb 12:116:110188. doi: 10.1016/j.jbiomech.2020.110188. Epub 2020 Dec 24. AuthorsManuela Ernst 1 , Heiko Baumgartner 2 , Stefan Döbele 2 , Dankward Höntzsch 2 , Tim Pohlemann 3 , Markus Windolf 4 Affiliations
AbstractCurrent fracture fixation follow-up is based on subjective radiological and clinical examination. Efforts to objectify the procedure have been undertaken since decades. Assessment of implant load as an indirect predictor of callus maturity has so far failed to enter clinical routine due to limited practicability, technical obstacles and its snap-shot nature. We recently introduced the concept of continuous implant load monitoring to aid in diagnosing fracture healing progression. This study aimed at investigating the feasibility of the system in a clinical context. Ten patients treated with Taylor-Spatial-Frame external fixators following pathological tibia fractures were equipped with a Fracture Monitor device attached to a fixator-strut and were monitored until hardware removal. Two patients were excluded due to technical issues. Implant load and fracture activity was continuously and autonomously measured for 139 ± 89 days (mean ± SD). Data was wirelessly collected with consumer smartphones. Relative implant load initially rose for 34.1 ± 22.2 days and finally declined to a level of 45.0 ± 33.8% of the maximum implant load. In five patients the load dropped below 50% of the maximum load. These patients underwent hardware removal according to the clinical assessment. In three patients, whose external fixators were exchanged to internal fixation at the end of the study, implant load did not drop below the 50% margin. The continuous measurement principle allows resolving implant load progression and appears indicative for the bone healing status. Data can be acquired in a homecare setting and is believed to provide valuable information to support timely healing assessment and enable patient specific after-care. Keywords: Fracture healing; Fracture monitoring; Healing assessment; Implant load; Nonunion. Copyright © 2020 Elsevier Ltd. All rights reserved. Conflict of interest statementDeclaration of Competing Interest The authors are not compensated and there are no other institutional subsidies, corporate affiliations or funding sources supporting this work unless clearly documented and disclosed. This study was performed with the assistance of the AO Technical Commission. Full text links |
| 39. | Pantoprazole impairs fracture healing in aged miceSci Rep. 2020 Dec 23;10(1):22376. doi: 10.1038/s41598-020-79605-3. AuthorsMaximilian M Menger 1 2 , Philipp Bremer 3 , Claudia Scheuer 3 , Mika F Rollmann 4 , Benedikt J Braun 4 , Steven C Herath 4 , Marcel Orth 5 , Thomas Später 3 , Tim Pohlemann 5 , Michael D Menger 3 , Tina Histing 3 4 Affiliations
AbstractProton pump inhibitors (PPIs) belong to the most common medication in geriatric medicine. They are known to reduce osteoclast activity and to delay fracture healing in young adult mice. Because differentiation and proliferation in fracture healing as well as pharmacologic actions of drugs markedly differ in the elderly compared to the young, we herein studied the effect of the PPI pantoprazole on bone healing in aged mice using a murine fracture model. Bone healing was analyzed by biomechanical, histomorphometric, radiological and protein biochemical analyses. The biomechanical analysis revealed a significantly reduced bending stiffness in pantoprazole-treated animals when compared to controls. This was associated with a decreased amount of bone tissue within the callus, a reduced trabecular thickness and a higher amount of fibrous tissue. Furthermore, the number of osteoclasts in pantoprazole-treated animals was significantly increased at 2 weeks and decreased at 5 weeks after fracture, indicating an acceleration of bone turnover. Western blot analysis showed a lower expression of the bone morphogenetic protein-4 (BMP-4), whereas the expression of the pro-angiogenic parameters was higher when compared to controls. Thus, pantoprazole impairs fracture healing in aged mice by affecting angiogenic and osteogenic growth factor expression, osteoclast activity and bone formation. Conflict of interest statementThe authors declare no competing interests. Full text links |
| 40. | Development of a dynamic fall risk profile in elderly nursing home residents: A free field gait analysis based studyArch Gerontol Geriatr. 2021 Mar-Apr:93:104294. doi: 10.1016/j.archger.2020.104294. Epub 2020 Nov 11. AuthorsEduard Witiko Unger 1 , Tina Histing 2 , Mika Frieda Rollmann 2 , Marcel Orth 1 , Esther Herath 3 , Maximilian Menger 2 , Steven Christian Herath 2 , Bernd Grimm 4 , Tim Pohlemann 1 , Benedikt Johannes Braun 5 Affiliations
AbstractFalls in nursing home residents are associated with a significant individual and socioeconomic burden of disease. To trigger and tailor individual intervention programs, solid early detection measures of residents at risk are needed. Aim of this study was thus to test the capability of a free field gait analysis insole to determine its usefulness in determining fall risk. In an observational study gait data of 22 nursing home residents over the age of 75 years was collected over one week with a measuring insole. Clinical scores were performed at baseline (POMA; DGI, TUG). For 6 months before and after the insole measurement, the fall events per resident were recorded. Correlation analysis as well as receiver operating characteristic curve analysis were performed. The average resident age was 88.2 years (range 78-99), 15 had at least one fall event. There was no significant correlation between clinical assessment and fall risk. Moderate correlations between different temporospatial parameters and fall risk were seen. Pressure distribution during gait was markedly changed in fallers. Differences between fallers and non-fallers as well as cut off values for increased fall risk in the ROC analysis could be determined. The introduced measurement protocol suggests that patients at risk for falling can be detected without any additional office visits. Based on the introduced protocol in a limited patient setting, further large scale studies should now determine the effect of prevention measures triggered by gait analysis, the specific risk reduction and the associated personal and socioeconomic advantages. Keywords: Dynamic gait analysis; Elderly; Fall risk. Copyright © 2020 Elsevier B.V. All rights reserved. Full text links |
| 41. | Anterior approaches to the acetabulum: which one to choose?EFORT Open Rev. 2020 Oct 26;5(10):707-712. doi: 10.1302/2058-5241.5.190061. eCollection 2020 Oct. AuthorsTim Pohlemann 1 , Steven C Herath 1 , Benedikt J Braun 1 , Mika F Rollmann 1 , Tina Histing 1 , Antonius Pizanis 1 Affiliation
AbstractSurgical treatment of acetabular fractures remains challenging even for experienced surgeons.Whilst the ilioinguinal and the Kocher-Langenbeck approach remain the standard procedures to expose the anterior or posterior aspects of the acetabulum, some modified anterior approaches for the stabilization of the acetabulum have been introduced.This article will provide an overview of approaches to the anterior aspect of the acetabulum and explain the efforts that have been made to improve the surgeon's options for certain fracture modifications, such as fractures with separation of the quadrilateral surface. Cite this article: EFORT Open Rev 2020;5:707-712. DOI: 10.1302/2058-5241.5.190061. Keywords: acetabular fracture; approach; osteosynthesis. © 2020 The author(s). Conflict of interest statementICMJE Conflict of interest statement: TP reports unrestricted research grants from AO Foundation, Werner, Siemens Stiftung, outside the submitted work. The other authors declare no conflict of interest relevant to this work. Full text links |
| 42. | Experimental induction of blunt chest trauma in mice: A modified approach with evaluation in dummies and cadaversExp Ther Med. 2020 Nov;20(5):28. doi: 10.3892/etm.2020.9156. Epub 2020 Aug 31. AuthorsDenis Höfer 1 , Christina Körbel 2 , Matthias W Laschke 2 , Nils T Veith 3 , Tim Pohlemann 3 , Reinhard Kappl 4 , Thomas Tschernig 1 Affiliations
AbstractExperimental chest trauma or blunt thoracic trauma using a blast wave mechanism is well established in animal models. The aim of the present study was to establish a complementary, murine experimental chest trauma model precisely defined by physical data and calculations. For this purpose, a device was developed using a dropped weight and physical properties, including velocity, energy and impact, were calculated. The device allowed for the maximum depth of impression to be measured. The device was first tested using blocks of modelling clay and was then applied to mouse cadavers. X-ray and dissection were performed to check for bone fractures and organ injuries following blunt chest traumas of increasing impact. Lesions and hemorrhages were observed in mouse cadavers which sustained a force equivalent to the energy of ~1 J. Keywords: blunt chest trauma; depth of impression; mouse model. Copyright: © HöFer et al. Full text links |
| 43. | A novel press-fit minimally-invasive symphysiodesis techniqueJ Exp Orthop. 2020 Sep 17;7(1):67. doi: 10.1186/s40634-020-00284-0. AuthorsSascha J Hopp 1 2 , Antonius Pizanis 1 , Jeremy Briem 1 , Jill Hahner 1 , Laura Mettelsiefen 1 , Steven C Herath 1 , Tina Histing 1 , Tim Pohlemann 1 , Tobias Fritz 3 Affiliations
AbstractObjective: Instability of the pubic symphysis often results in a poor outcome and reduced mobility of the patient. In some cases, an arthrodesis of the pubic symphysis is required. Until today, there is no data published how many of these procedures are performed annually and there is also no data about the outcome after this extensive surgery. Methods: We developed a novel surgical technique to address the arthrodesis of the pubic symphysis in a minimally invasive approach. Therefore, we used for this purpose modified instruments and performed the transplantation of a cylindrical bone substitute into the pubic symphysis, without an extensive approach or dissecting the anterior or posterior symphyseal ligaments. Results: Using this novel technique, a minimally invasive symphysiodesis was achieved in radiological findings, after the procedure. Conclusion: Thus, this actually minimally invasive surgical technique seems to be a promising advancement for the arthrodesis of the pubic symphysis. Keywords: Arthrodesis Symphysis; Non-union Symphysis; Pelvis; Pubic Symphysis; Symphysiodesis. Conflict of interest statementThere is no conflict of interest. The instruments for this article have been developed in collaboration with and provided by KARL STORZ, Tuttlingen, Germany. This study has not been funded. Full text links |
| 44. | Vascularization Strategies in the Prevention of Nonunion FormationTissue Eng Part B Rev. 2021 Apr;27(2):107-132. doi: 10.1089/ten.TEB.2020.0111. Epub 2020 Aug 26. AuthorsMaximilian M Menger 1 , Matthias W Laschke 2 , Marcel Orth 1 , Tim Pohlemann 1 , Michael D Menger 2 , Tina Histing 1 Affiliations
AbstractDelayed healing and nonunion formation are major challenges in orthopedic surgery, which require the development of novel treatment strategies. Vascularization is considered one of the major prerequisites for successful bone healing, providing an adequate nutrient supply and allowing the infiltration of progenitor cells to the fracture site. Hence, during the last decade, a considerable number of studies have focused on the evaluation of vascularization strategies to prevent or to treat nonunion formation. These involve (1) biophysical applications, (2) systemic pharmacological interventions, and (3) tissue engineering, including sophisticated scaffold materials, local growth factor delivery systems, cell-based techniques, and surgical vascularization approaches. Accumulating evidence indicates that in nonunions, these strategies are indeed capable of improving the process of bone healing. The major challenge for the future will now be the translation of these strategies into clinical practice to make them accessible for the majority of patients. If this succeeds, these vascularization strategies may markedly reduce the incidence of nonunion formation. Impact statement Delayed healing and nonunion formation are a major clinical problem in orthopedic surgery. This review provides an overview of vascularization strategies for the prevention and treatment of nonunions. The successful translation of these strategies in clinical practice is of major importance to achieve adequate bone healing. Keywords: VEGF; angiogenesis; bone formation; bone healing; cell therapy; delayed healing; nonunion; scaffold; tissue engineering; vascularization. Full text links |
| 45. | Azetabulumfrakturen – Zugänge und Implantate im WandelZ Orthop Unfall. 2020 Jun;158(3):353-363. doi: 10.1055/a-0900-4533. Epub 2020 Jun 17. [Article in German] AuthorsTina Histing, Steven C Herath, Antonius Pizanis, Tim Pohlemann
No abstract available Conflict of interest statementDie Autoren geben an, dass kein Interessenkonflikt besteht. Full text links |
| 46. | Flexor tendon grafts for pulley reconstruction - Morphological aspectsAnn Anat. 2020 Sep:231:151550. doi: 10.1016/j.aanat.2020.151550. Epub 2020 Jun 5. AuthorsTobias Fritz 1 , Pascal Ducommun 2 , Tim Pohlemann 3 , Maurizio Calcagni 4 , Thomas Tschernig 5 , Michael D Menger 6 , Wolfgang Metzger 3 , Florian S Frueh 7 Affiliations
Free article AbstractBackground: Pulleys are crucial to convert flexor tendon excursion into angular motion at the metacarpophalangeal and interphalangeal joints. Loss of pulley function can lead to significant impairment of hand function and may require surgical reconstruction. This reconstruction can be achieved using different flexor tendons grafts, such as the intrasynovial flexor digitorum superficialis (FDS) or the extrasynovial palmaris longus (PL). However, there is limited knowledge on the micromorphology of human pulleys and the suitability of flexor tendon grafts for their reconstruction remains elusive. Methods: In the present cadaver study A2 and A4 pulleys were compared with FDS and PL tendons by means of scanning electron microscopy (SEM), histology and immunohistochemistry. Surface morphology, core structure and vascularization of the specimens were analyzed. Results: SEM imaging of the gliding surfaces revealed morphological differences between tendons and pulleys. Moreover, the core structure of FDS samples was characterized by bundles of individual collagen fibrils whereas PL tendons exhibited a less hierarchical microstructure. In contrast, pulleys consisted of lamellar sheets of densely packed collagen fibrils. Finally, immunohistochemical analyses revealed that the flexor tendons and pulleys contain similar numbers of CD31+ microvessels, indicating a comparable tissue vascularization. Conclusion: This study provides novel SEM and immunohistochemical insights into the micromorphology of human pulleys and flexor tendon grafts. Intrasynovial flexor tendons may be particularly suitable for pulley reconstruction and preserving the paratenon may be crucial for graft revascularization. Keywords: Flexor digitorum superficialis; Flexor tendon graft; Hand surgery; Palmaris longus; Pulley reconstruction; Pulley vascularization. Copyright © 2020 The Authors. Published by Elsevier GmbH.. All rights reserved. Full text links |
| 47. | How effective are different models of pelvic binders: results of a study using a Pelvic Emergency SimulatorEur J Trauma Emerg Surg. 2022 Apr;48(2):847-855. doi: 10.1007/s00068-020-01406-0. Epub 2020 May 26. AuthorsUwe Schweigkofler # 1 , Dennis Wincheringer # 2 , Jörg Holstein 3 , Tobias Fritz 4 , Reinhard Hoffmann 5 , Tim Pohlemann 4 , Steven C Herath 4 Affiliations
# Contributed equally.
AbstractBackground: The application of pelvic binders in the preclinical and early clinical phase is advisable to avoid or treat C-problems in unstable and potential bleeding pelvic ring fractures, even if the clinical effectivity is not completely proved. The use for pathologies in the posterior pelvic ring is still debatable. Questions/purposes: We determined if there is a difference in achievable compression in the dorsal pelvic ring depending on position and pelvic binder model. Can this effect be tested with a simplified artificial model? Methods: We simulated a Tile type C fracture within the established pelvic emergency trainer and measured in a test series the effectivity of reduction with a non-invasive stabilization technique using 3 different pelvic binders. Results: Any therapeutic effect of a pelvic binder with compression to the posterior pelvic ring requires at first a reduction maneuver. While the compression effect in the symphysis depends only on positioning of the binder, in the posterior pelvic ring, the result varies with the used model. The achievable pressure in the SI joint with a pelvic binder is only 20-25% (33.5-47 N) compared to the C-Clamp values (156 N). Conclusions: The use of pelvic binders for non-invasive pelvic ring stabilization, even with a posterior pathology, could be proven in a simplified fracture model. A proper fracture reduction and an adequate device positioning influence the effectiveness. Clinical relevance: The use of an emergency pelvic trainer even for a non-invasive maneuver is advisable. Keywords: Pelvic binder; Pelvic emergency trainer; Pelvic ring fracture. © 2020. Springer-Verlag GmbH Germany, part of Springer Nature. Full text links |
| 48. | A novel internal fixation method for open book injuries of the pubic symphysis- A biomechanical analysisClin Biomech (Bristol, Avon). 2020 Jul:77:105009. doi: 10.1016/j.clinbiomech.2020.105009. Epub 2020 May 5. AuthorsTobias Fritz 1 , Laura Mettelsiefen 2 , Friedemann Strobel 2 , Benedikt J Braun 3 , Steven C Herath 4 , Sascha J Hopp 5 , Tina Histing 6 , Tim Pohlemann 7 , Antonius Pizanis 8 Affiliations
AbstractBackground: Pelvic fractures in adults are common injuries and account for up to 3.64% of all fractures. Usually, the treatment of open book injuries (Types B1.1 and B1.2 AO-Classification) is open reduction and plate stabilization using dynamic compression plates, with or without interlocking screws. These implants seem to enhance the outcome of such injuries, but also variety of complications occurs. To reduce complications and achieve appropriate reduction and stabilization, this study compared established stabilization techniques to a novel minimally invasive internal fixation method using an internal fixator system that is already being utilized for spinal fractures. Methods: This study was performed on 32 composite pelvises in a bilateral stance biomechanical model. The pelvises were variously stabilized with an internal fixator, a 4.5 mm dynamic compression plate and a 3.5 mm symphyseal locking dynamic compression plate. The contact area and loading forces were assessed by a sensor film inside the symphyseal gap. Findings: This study showed significantly greater reduction and loading capabilities of the internal fixator compared to the other implants (p < 0.05). There was also significantly greater contact area with the use of an internal fixator compared to the other implants (p < 0.05). The 3.5 mm interlocking plate showed significantly greater contact area compared to the 4.5 mm plate (p < 0.05). Interpretation: The internal fixator that is already proven in spinal surgery is biomechanically superior to conventional implants used in pelvic surgery. The contact area analysis furthermore showed a more physiological loading pattern, which can improve ligamentous healing in a clinical context. Keywords: Compression forces symphysis; Internal fixator; Open Book injury; Symphysis. Copyright © 2020 Elsevier Ltd. All rights reserved. Conflict of interest statementDeclaration of competing interest The authors state that there is no conflict of interest and do not work as consultants or have patent applications related to this article. Full text links |
| 49. | Long-term results of reconstructing the joints' articular surface in the knee and ankle with the surgical diamond instrumentation (SDI)Eur J Trauma Emerg Surg. 2021 Oct;47(5):1627-1634. doi: 10.1007/s00068-020-01318-z. Epub 2020 Feb 21. AuthorsMika Frieda Rollmann 1 , Steven Christian Herath 2 , Tina Histing 2 , Benedikt Johannes Braun 2 , Julia Schmalenbach 2 , Yvette Draenert 3 , Klaus Draenert 3 , Tim Pohlemann 2 Affiliations
AbstractPurpose: The surgical diamond instrumentation (SDI), a precise wet-grinding technology, promised contact healing of press-fit inserted bone and even hyaline cartilage, lacks medium- and long-term results. This retrospective study was conducted to identify risk factors associated with the failure of the technique and the subjective patient outcome. Methods: All patients treated for cartilage defects of the knee or ankle joint using the SDI technology between 2000 and 2012 with a follow-up > 1 year were included. Patients with general joint diseases or joint-related procedures, except for corrective osteotomies, were excluded. A standardized questionnaire (EQ-5D) and a questionnaire-based patient-reported outcome survey were used. Descriptive statistics were applied. A multivariate analysis examining risk factors for joint failure was performed. A p value < 0.05 was considered to indicate significant differences. Results: 87 patients with autologous osteochondral transplantation (68 knee, 19 ankle) were included. The median age was 53 years (IQR 37.5-63.0 years) for knee and 36 years (IQR 27.5-54.0 years) for ankle joints. 57.9% of knee and 55.6% of ankle patients were female. Nine patients (8 knee, 1 ankle) had received arthroplasty. 93.3% of knee and 83.3% of ankle patients had an excellent function or minor disabilities. 73.3% of knee and 64.7% of ankle patients did not require pain medication. The mean EQ-5D score was 0.84 for knee and 0.77 for ankle. Patients with higher age were more likely to receive arthroplasty (p = 0.022). Conclusions: The SDI technique provides promising results with excellent joint survival rates and satisfying patient-reported outcomes. Failure of the technique might be associated with higher age. Keywords: Autologous resurfacing; Cartilage repair; Quality of life; Reconstruction of joints; Surgical diamond instrumentation. © 2020. Springer-Verlag GmbH Germany, part of Springer Nature. Full text links |
| 50. | Interacting adipose-derived stem cells and microvascular endothelial cells provide a beneficial milieu for soft tissue healingMol Biol Rep. 2020 Jan;47(1):111-122. doi: 10.1007/s11033-019-05112-y. Epub 2019 Oct 3. AuthorsSophie Bachmann 1 , Martina Jennewein 1 , Monika Bubel 1 , Silke Guthörl 1 , Tim Pohlemann 1 , Martin Oberringer 2 Affiliations
AbstractThere is growing evidence suggesting that healing of chronic soft tissue wounds profits from the presence of adipose-derived stem cells (ADSC). Among the large spectrum of mechanisms by which ADSC might act, especially the interaction with the microvascular endothelial cell, a main player during angiogenesis, is of special interest. In the present 2D model on the basis of endothelial cell ADSC co-cultures, we focused on the identification of characteristics of both cell types in response to a typical condition in acute and chronic wounds: hypoxia. Parameters like proliferation capacity, migration, myofibroblastoid differentiation of ADSC and the quantification of important paracrine factors related to angiogenesis and inflammation were used to correlate our experimental model with the in vivo situation of soft tissue healing. ADSC were not negatively affected by hypoxia in terms of proliferation, referring to their excellent hypoxia tolerance. Myofibroblastoid differentiation among ADSC was enhanced by hypoxia in mono- but not in co-culture. Furthermore, co-cultures were able to migrate under hypoxia. These effects might be caused to some extent by the distinct milieu created by interacting ADSC and endothelial cells, which was characterized by modulated levels of interleukin-6, interleukin-8, monocyte chemoattractant protein-1 and vascular endothelial growth factor. The identification of these cell characteristics in the present 2D in vitro model provide new insights into the process of human soft tissue healing, and underpin a beneficial role of ADSC by regulating inflammation and angiogenesis. Keywords: Adipose-derived stem cell; Angiogenesis; Co-culture; Hypoxia; Inflammation; Microvascular endothelial cell; Myofibroblastoid differentiation; Soft tissue healing. Full text links |
| 51. | Stabilization of a Type B1.1 Injury in a Morbidly Obese Patient Using an Internal Fixator in a Minimally Invasive Technique: A Case ReportJBJS Case Connect. 2019 Jul-Sep;9(3):e0075. doi: 10.2106/JBJS.CC.18.00075. AuthorsTobias Fritz 1 , Benedikt J Braun 1 , Nils T Veith 1 , Sascha J Hopp 1 2 , Laura Mettelsiefen 1 , Friedemann Strobel 1 , Tim Pohlemann 1 , Antonius Pizanis 1 Affiliations
AbstractCase: In this case report, we present a novel stabilization technique of the pubic symphysis using an internal spinal fixator in a 78-year-old morbidly obese woman having a pelvic disruption type B1.1 (AO classification). We treated the disruption using an internal fixator to reduce the extent of the incision and soft-tissue damage. Conclusions: The use of an internal fixator, known from percutaneous spinal fixation, for the stabilization of the pubic symphysis in cases of disruption ("open book" injuries) may be an alternative to the standard plate fixation as a novel minimally invasive stabilization technique. Full text links |
| 52. | Controlling fibroblast adhesion and proliferation by 1D Al2O3 nanostructuresIET Nanobiotechnol. 2019 Aug;13(6):621-625. doi: 10.1049/iet-nbt.2018.5088. AuthorsOral Cenk Aktas 1 , Wolfgang Metzger 2 , Lisa Mees 2 , Marina Miro Martinez 3 , Ayman Haidar 4 , Martin Oberringer 2 , Gunther Wennemuth 5 , Norbert Pütz 6 , Muhammad Zubair Ghori 7 , Tim Pohlemann 2 , Michael Veith 3 Affiliations
AbstractThe fibrotic encapsulation, which is mainly accompanied by an excessive proliferation of fibroblasts, is an undesired phenomenon after the implantation of various medical devices. Beside the surface chemistry, the topography plays also a major role in the fibroblast-surface interaction. In the present study, one-dimensional aluminium oxide (1D Al2O3) nanostructures with different distribution densities were prepared to reveal the response of human fibroblasts to the surface topography. The cell size, the cell number and the ability to form well-defined actin fibres and focal adhesions were significantly impaired with increasing distribution density of the 1D Al2O3 nanostructures on the substratum. Full text links |
| 53. | Profiling microRNA expression in murine bone healing and non-union formation: Role of miR-140 during the early stage of bone healingPLoS One. 2019 Jul 19;14(7):e0218395. doi: 10.1371/journal.pone.0218395. eCollection 2019. AuthorsMarcel Orth 1 2 , Claudia Scheuer 2 , Christina Backes 3 , Andreas Keller 3 , Mika F Rollmann 1 , Benedikt J Braun 1 , Nicole Ludwig 4 , Eckart Meese 4 , Tim Pohlemann 1 , Matthias W Laschke 2 , Michael D Menger 2 , Tina Histing 1 2 Affiliations
AbstractAlthough cellular and molecular mechanisms during the course of bone healing have been thoroughly investigated, the regulation of gene expression by microRNA during bone regeneration is still poorly understood. We hypothesized that nonunion formation is associated with different microRNA expression patterns and that target proteins of these microRNAs are differently expressed in callus tissue of nonunions compared to physiologically healing bones. In a well-established femoral osteotomy model in CD-1 mice osteotomies were induced which result either in healing or in nonunion formation. MicroRNA and target protein expression was evaluated by microarray, quantitative real-time polymerase chain reaction (qrt-PCR) and Western blot. Microarray analyses demonstrated 44 microRNAs to be relevant for nonunion formation compared to physiological bone healing. In nonunions qrt-PCR could validate a higher expression of microRNA-140-3p and microRNA-140-5p. This was associated with a reduced expression of Dnpep and stromal cell-derived factor (SDF)-1α, which are both known to be target proteins of microRNA-140 and also to be involved in the process of bone healing. These data suggest that an increased expression of microRNA-140-3p and microRNA-140-5p markedly contributes to the development of nonunions, most probably by affecting bone morphogenetic protein (BMP)-2 function during the early stage of healing due to a reduced SDF-1α expression. Conflict of interest statementThe authors have declared that no competing interests exist. Full text links |
| 54. | Increased therapy demand and impending loss of previous residence status after proximal femur fractures can be determined by continuous gait analysis - A clinical feasibility studyInjury. 2019 Jul;50(7):1329-1332. doi: 10.1016/j.injury.2019.05.007. Epub 2019 May 18. AuthorsBenedikt J Braun 1 , David Osche 2 , Mika Rollmann 2 , Marcel Orth 2 , Philipp Mörsdorf 2 , Tina Histing 2 , Tim Pohlemann 2 , Steven C Herath 2 Affiliations
AbstractProximal femur fractures account for increased healthcare costs whenever patients are unable to return to their previous state of residence. Studies suggest that patients benefit from early weight-bearing, yet compliance to weight-bearing regimes is poorly investigated. Aim of the study was thus to show the clinical feasibility of a new measurement tool able to determine continuous weight-bearing behavior after intramedullary nail osteosynthesis of intertrochanteric femur fractures, assess the influence of weight-bearing on clinical outcome and determine rehabilitation demand based on early postoperative gait performance. In an observational study, gait data of 22 patients with intertrochanteric femur fractures were evaluated. During the inpatient stay patients were continuously monitored with a gait analysis insole. Primary outcome was the amount of weight-bearing reached. Short-term functional outcome, as well as return to the previous state of living were evaluated in relation to weight-bearing and activity during the inpatient stay. With the presented technique continuous gait data of all patients during postoperative mobilization could be obtained. Only 13 patients reached full weight-bearing. The technique was feasible to determine correlations between weight-bearing and outcome, as well as between gait activity and outcome. Significant gait differences between patients able to return to their previous state of living and those who could not were seen. Dynamic insole measurements are feasible to continuously determine the postoperative gait performance. Their postoperative use showed, that the continuous compliance to permissive weight-bearing after intertrochanteric fractures is low. The presented measurement technique has the potential to identify patients at risk for reduced outcome and impending loss of previous residence status. Further studies will have to investigate the effects of technology assisted "patient at risk" identification and adapted therapy on clinical outcome. Keywords: Aftercare; Elderly; Hip fractures; Weight-bearing. Copyright © 2019. Published by Elsevier Ltd. Full text links |
| 55. | Autologous Transplantation of Press-fit Bone Cylinders in the Treatment of Pelvic NonunionOrthop Surg. 2019 Jun;11(3):516-523. doi: 10.1111/os.12463. Epub 2019 May 3. AuthorsSteven C Herath 1 , Benedikt J Braun 1 , Mika F Rollmann 1 , Philipp Mörsdorf 1 , Jörg H Holstein 1 , Tim Pohlemann 1 Affiliation
AbstractThe present study describes method for autologous bone transplantation to an area of nonunion at the pelvic ring in a way that ensures the best possible bone-to-bone interface ("press-fit") and provides optimal preconditions for the ingrowth of the bone graft. We modified a technique that has been used to transplant press-fit bone-baseplate-cartilage cylinders for the repair of joint cartilage defects. The technique allows for precise harvesting of bone cylinders with a diamond-coated and fluid-cooled instrument. At the site where the graft shall be inserted, a cylindrical hole is created with a corresponding hollow diamond-coated trephine. This ensures an optimal press-fit implantation of the graft. The new surgical technique has been applied in four patients with nonunion of the pelvic ring. No intraoperative or postoperative complications occurred. In three patients, the procedure led to a reduction of pain and a higher level of mobility as well as a timely radiographic union (imaging not available for another patient). Our technique offers a valuable new treatment option for pelvic nonunion. The current article serves as a proof of concept. Future comparative studies will have to determine its value in detail. Keywords: Bone graft; Nonunion; Pelvic ring fracture; Press-fit cylinder; Treatment. © 2019 The Authors. Orthopaedic Surgery published by Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd. Full text links |
| 56. | Erythropoietin does not improve fracture healing in aged miceExp Gerontol. 2019 Jul 15:122:1-9. doi: 10.1016/j.exger.2019.04.005. Epub 2019 Apr 16. AuthorsM Orth 1 , J Baudach 2 , C Scheuer 3 , D Osche 2 , N T Veith 4 , B J Braun 4 , M F Rollmann 4 , S C Herath 4 , T Pohlemann 4 , M D Menger 3 , T Histing 2 Affiliations
AbstractFracture healing in the elderly is associated with a declined healing potential caused by multiple factors including a delay of vascularization. Erythropoietin (EPO) has been demonstrated to improve vascularization and fracture healing in adult mice. We, therefore, hypothesized that EPO in aged mice also improves fracture healing. For this purpose, EPO was given daily in a femoral fracture model in aged mice and compared to vehicle-treated controls using radiological, biomechanical, histomorphometric and Western blot techniques. Blood analyses revealed significantly higher concentrations of hemoglobin and a higher hematocrit in EPO-treated animals at 14 and 35 days after fracture. Micro-computed tomography (μCT) indicated that the fraction of bone volume/tissue volume within the callus did not differ between the two groups. However, μCT showed a 3-fold increased tissue mineral density (TMD) in the callus of EPO-treated animals compared to controls. The callus TMD of the EPO-treated animals was also 2-fold higher when compared to the TMD of the unfractured contralateral femur. Interestingly, biomechanical analyses revealed a reduced bending stiffness in femurs of EPO-treated animals at day 35. The histomorphometrically analyzed callus size and callus composition did not show significant differences between the study groups. However, Western blot analyses exhibited an increased expression of osteoprotegerin (OPG), but in particular of receptor activator of NF-κB ligand (RANKL) in the callus of the EPO-treated animals. Further histological analyses of the callus tissue showed that this was associated with an increased number of newly formed blood vessels and a higher number of tartrate-resistant acid phosphatase (TRAP)+ cells. Conclusion: In fracture healing of aged mice EPO treatment increases callus TMD as well as OPG and RANKL expression, indicating an accelerated bone turnover when compared to controls. However, EPO does not improve fracture healing in aged mice. The process of fracture healing may be altered by EPO due to a deterioration of the microcirculation caused by the worsened rheological properties of the blood and due to an increased bone fragility caused by the accelerated bone turnover. Thus, EPO may not be used to improve fracture healing in the elderly. Keywords: Aged mice; Bone healing; Bone turnover; EPO; Fracture healing; Tissue mineral density. Copyright © 2019 Elsevier Inc. All rights reserved. Full text links |
| 57. | VEGF-loaded mineral-coated microparticles improve bone repair and are associated with increased expression of epo and RUNX-2 in murine non-unionsJ Orthop Res. 2019 Apr;37(4):821-831. doi: 10.1002/jor.24267. Epub 2019 Mar 28. AuthorsMarcel Orth 1 2 , Amira K Shenar 1 2 , Claudia Scheuer 2 , Benedikt J Braun 1 , Steven C Herath 1 , Jörg H Holstein 1 2 , Tina Histing 1 2 , Xiaohua Yu 3 , William L Murphy 3 , Tim Pohlemann 1 , Matthias W Laschke 2 , Michael D Menger 2 Affiliations
Free article AbstractA poor vascular supply of the fracture gap is a key factor for the development of atrophic non-unions. Mineral-coated microparticles (MCM) represent a sophisticated carrier system for the delivery of vascular endothelial growth factor (VEGF). Hence, we investigated whether VEGF-loaded MCM improve bone repair in non-unions. For this purpose, we analyzed binding and release kinetics of MCM for VEGF in vitro. Moreover, we applied VEGF-loaded or -unloaded MCM in a murine non-union model in vivo and studied the process of bone healing by means of biomechanical, radiological, histomorphometric, and Western blot techniques. MCM-free non-unions served as controls. The binding efficiency of MCM for VEGF was 46 ± 3% and the release profile revealed an initial minor burst release followed by a sustained release over a 50-day study period, thus, mimicking the physiological expression profile of VEGF during bone healing. In vivo, bone defects treated with VEGF-loaded MCM exhibited a higher bending stiffness, a higher fraction of bone volume/tissue volume and a larger callus area on days 14 and 70 when compared to the other groups. Western blot analyses on day 14 revealed a higher expression of VEGF, erythropoietin (EPO), and runt-related transcription factor 2, but not of EPO-receptor in bone defects treated with VEGF-loaded MCM. These findings demonstrate that the use of MCM for VEGF delivery shows great potential due to the ability to maintain protein stability and functionality in vivo. Moreover, the application of VEGF-loaded MCM represent a promising strategy for the treatment of non-unions. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. Keywords: VEGF; bone healing; mineral coated microparticles; non-union. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. Full text links |
| 58. | Cement augmentation of the proximal humerus internal locking system in elderly patients: a multicenter randomized controlled trialArch Orthop Trauma Surg. 2019 Jul;139(7):927-942. doi: 10.1007/s00402-019-03142-6. Epub 2019 Feb 25. AuthorsClemens Hengg 1 , Stefaan Nijs 2 , Tim Klopfer 3 , Martin Jaeger 4 , Andreas Platz 5 , Tim Pohlemann 6 , Reto Babst 7 , Jochen Franke 8 , Franz Kralinger 9 10 Affiliations
AbstractIntroduction: Cement augmentation of the proximal humerus internal locking system (PHILOS) screws might reduce complication rates in osteoporotic bones. This study compared the risk of mechanical failure during the first year after PHILOS™ treatment of proximal humerus fractures (PHF) without (control group) and with (augmented group) screw augmentation. Secondary objectives were to report shoulder functions, quality of life (QoL), adverse events (AEs), and reoperation rates. Materials and methods: This multicenter randomized trial enrolled patients aged ≥ 65 years with displaced/unstable PHF from eight European centers. Randomization was performed during surgery through sealed opaque envelopes. Mechanical failures were assessed by two independent reviewers via radiographs, shoulder function by Quick DASH, SPADI, and Constant Murley scores, and QoL by EQ-5D. Follow-ups were planned at postoperative 6 weeks, 3, 6, and 12 months. Results: The preliminary analysis of 6-week radiographs of the first 59 enrolled patients suggested a mechanical failure rate lower than expected and the difference between groups was too small to be detected by the planned sample size of 144. The trial was prematurely terminated after 67 patients had been enrolled: 34 (27 eligible) in the control group and 33 (29 eligible) in the augmented group. Follow-ups were performed as planned. Nine patients had mechanical failures and the failure rates (95% CI) were: augmented group, 16.1% (5.5; 33.7); control group, 14.8% (4.2; 33.7); the relative risk (95% CI) for the augmented group was 1.09 (0.32; 3.65) compared to the control group (p = 1.000). No statistically significant differences in shoulder function, QoL, and AEs were observed between study groups at 1 year. Nine patients (15.8%) underwent a revision. Conclusions: Due to premature termination, the study was underpowered. A larger study will be necessary to determine if cement augmentation lowers the risk of mechanical failure rate. Keywords: Augmentation; Multicenter randomized trial; Osteoporosis; PHILOS; Proximal humerus fracture; Proximal humerus internal locking system. Conflict of interest statementFranz Kralinger is a consultant with DePuySynthes but did not receive personal benefits for the current study. Tim Pohlemann was the chairman of the AO TK-System during the time of study. Martin Jaeger is a member of the AO UEEG. Full text links |
| 59. | Geriatric Acetabular Surgery: Letournel's Contraindications Then and Now-Data From the German Pelvic RegistryJ Orthop Trauma. 2019 Feb:33 Suppl 2:S8-S13. doi: 10.1097/BOT.0000000000001406. AuthorsSteven C Herath 1 , Hendrik Pott 1 , Mika F R Rollmann 1 , Benedikt J Braun 1 , Jörg H Holstein 1 , Andreas Höch 2 , Fabian M Stuby 3 , Tim Pohlemann 1 Affiliations
AbstractObjective: In his original series of 129 surgically treated acetabular fractures, Letournel did not operate on patients older than 60 years. Almost 30 years later, he still emphasized that no patients with reduced bone quality should be operated on. The aim of the study was to analyze epidemiologic characteristics and treatment modes for today's cohort of elderly patients with acetabular fractures. Design: Retrospective analysis. Setting: Multicenter registry/Level I trauma center. Patients: Three thousand seven hundred ninety-three patients who had sustained a fracture of the acetabulum. Intervention: Operative and nonoperative treatment of acetabular fractures. Main outcome measurements: Epidemiologic characteristics, treatment mode, in-hospital mortality, rate of secondary hip arthroplasty, and quality of life indicated by EQ-5D score. Results: For the multicenter registry, more than 50% of all patients with acetabular fractures had an age of 60 years or over. The age peak was found at 75-80 years. Fifty percent of the elderly patients were treated surgically. The in-hospital mortality was significantly higher in elderly patients than patients younger than 60 years. In our Level I trauma center, surgical treatment by open reduction and internal fixation did not influence in-hospital mortality or quality of life of elderly patients with acetabular fractures. Conclusions: Today, elderly persons represent the dominant cohort among patients with fractures of the acetabulum. Fifty-five years after the publication of Letournel's original case series, data indicate that currently, surgical treatment is a common and necessary option in the therapy of acetabular fractures in elderly patients. Level of evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. Full text links |
| 60. | Targeted Endocrine Therapy: Design, Synthesis, and Proof-of-Principle of 17β-Hydroxysteroid Dehydrogenase Type 2 Inhibitors in Bone Fracture HealingJ Med Chem. 2019 Feb 14;62(3):1362-1372. doi: 10.1021/acs.jmedchem.8b01493. Epub 2019 Jan 15. AuthorsAhmed S Abdelsamie 1 2 , Steven Herath, Yannik Biskupek, Carsten Börger 3 , Lorenz Siebenbürger 3 , Mohamed Salah 4 , Claudia Scheuer, Sandrine Marchais-Oberwinkler 5 , Martin Frotscher 4 , Tim Pohlemann, Michael D Menger, Rolf W Hartmann 4 6 , Matthias W Laschke, Chris J van Koppen 1 4 Affiliations
AbstractCurrent therapies of steroid hormone-dependent diseases predominantly alter steroid hormone concentrations (or their actions) in plasma, in target and nontarget tissues alike, rather than in target organs only. Targeted therapy through the inhibition of steroidogenic enzymes may pose an attractive alternative with much less side effects. Here, we describe the design of a nanomolar potent 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2) inhibitor (compound 15) and successful targeted intracrine therapy in a mouse bone fracture model. Blockade of 17β-HSD2 in bone is thought to increase intracellular estradiol (E2) and testosterone (T), which thereby inhibits bone resorption by osteoclasts and stimulates bone formation by osteoblasts, respectively. Administration of compound 15 in the mouse fracture model strongly increases the mechanical stability of the healing fractured bone because of a larger periosteal callus with newly formed bone without changing the plasma E2 and T concentrations. Steroidogenic 17β-HSD2 inhibition thus enables targeted intracrine therapy. Full text links |
| 61. | In-hospital mortality of pelvic ring fractures in older adults now and then: A pelvic registry studyGeriatr Gerontol Int. 2019 Jan;19(1):24-29. doi: 10.1111/ggi.13558. Epub 2018 Dec 26. AuthorsMika F Rollmann 1 , Steven C Herath 1 , Benedikt J Braun 1 , Joerg H Holstein 1 , Tim Pohlemann 1 , Michael D Menger 2 , Tina Histing 1 Affiliations
AbstractAim: With the predicted demographic change, the treatment of geriatric patients will become a major issue for health systems worldwide. The majority of pelvic ring fractures occur in older adults, and their treatment might be associated with a distinct mortality. Herein, we analyzed the data of 5665 patients with pelvic ring fractures aged ≥60 years included in the German Pelvic Trauma Registry from 1991 to 2013. Methods: The data were collected prospectively, multicentrically in hospitals participating in the German Pelvic Trauma Registry. Demographic data were retrospectively analyzed, stratified for age, sex, type of injury, mode of therapy, injury severity score (ISS) and mortality. Results: The overall mortality decreased over the 22-year study period from 9.3% to 3.8% (P < 0.05), whereas the median ISS significantly increased. During the observation period, mortality was higher in patients with type B and, particularly, type C fractures when compared with patients with type A fractures. Mortality rates of patients aged >80 years did not significantly differ from those aged >60 or >70 years. Male patients showed a significantly higher mortality compared with female patients, as well as a significantly higher median ISS. The mortality rate of patients with surgically-treated type C fractures decreased over the study period from 35.7% to 6.9% (P < 0.05). Conclusions: Over the past two decades, the mortality of older patients after pelvic ring fractures has significantly decreased. The higher overall mortality rate of male patients might mainly be accounted for by the relatively higher fraction of type C fractures and a higher ISS. Geriatr Gerontol Int 2019; 19: 24-29. Keywords: German Pelvic Trauma Registry; mortality of pelvic ring fractures; pelvic ring fractures. © 2018 Japan Geriatrics Society. Full text links |
| 62. | Marble-derived microcalcite improves bone healing in mice osteotomyBiomed Mater. 2018 Dec 7;14(2):025001. doi: 10.1088/1748-605X/aaee54. AuthorsMarcel Orth 1 , Takhirjan Shadmanov, Claudia Scheuer, Benedikt J Braun, Tobias Fritz, Jörg H Holstein, Tina Histing, Matthias W Laschke, Tim Pohlemann, Michael D Menger Affiliation
AbstractApproximately 10% of all fractures result in delayed healing or non-unions. Bone healing can be improved by the application of osteoconductive and osteoinductive biomaterials. Microcalcite (MCA) as a naturally available calcium carbonate-based biomaterial derived from marble may have the potential to improve bone healing. Herein, we studied for the first time, if MCA in combination with platelet-rich plasma (PRP) can be used as a bone graft material for bone healing in vivo. For this purpose, osteotomies were induced in CD-1 mice (n = 60). Animals received into the osteotomy gap either MCA-loaded PRP (MCA + PRP; n = 20), PRP alone (PRP; n = 20) or no application (NONE; n = 20). Bone healing was evaluated at two and five weeks after osteotomy by micro-computed tomography (μCT), histomorphometric, immunohistochemical and Western Blot analyses. μCT of MCA + PRP femurs revealed more bone volume and an increased polar moment of inertia, indicating a higher biomechanical stability when compared to PRP and NONE femurs. Histomorphometry revealed an increased total callus area after two weeks and a reduced callus tissue area after five weeks in MCA + PRP and PRP animals compared to NONE animals, indicating an accelerated process of bone healing and remodeling over the study period. Moreover, histomorphometric analyses demonstrated an increased fraction of osseous tissue within the callus in MCA + PRP femurs when compared to PRP and NONE femurs. Immunohistochemical analyses showed increased numbers of Ki67+ cells in callus tissue of MCA + PRP femurs. Of interest, Western Blotting revealed a significantly reduced expression of BMP-4 in MCA + PRP animals, while the expression of BMP-2 did not reveal any significant differences between the groups. This indicates a modified balance between angiogenesis and osteogenesis due to MCA. In conclusion, the application of MCA with PRP improved bone healing in a murine osteotomy model and, thus, might be a promising novel bone graft material which may be of interest for clinical fracture treatment. Full text links |
| 63. | Should I Stay or Should I Go? A Prospective, Blinded Study Comparing the Diagnostic Capability of Dynamic and Stationary Pedobarography in Plantar FasciitisJ Foot Ankle Surg. 2018 Nov-Dec;57(6):1181-1185. doi: 10.1053/j.jfas.2018.06.015. AuthorsBenedikt J Braun 1 , Christine Huss 2 , Sina Heimueller 3 , Moritz Klein 4 , Steven C Herath 4 , Christian Ruebe 5 , Tim Pohlemann 6 , Marcus Niewald 7 Affiliations
AbstractThe aim of this study was to determine the diagnostic capability of a dynamic gait analysis insole and compare its ability to detect clinical correlations to a common stationary analysis tool. Twenty-five patients with chronic plantar fasciitis were included in this prospective, blinded, diagnostic study. Conventional, stationary gait analysis on a force plate on an even surface and continuous dynamic pedobarography on a standardized course consisting of different gait tasks were performed and correlated to the disease severity. Mean patient age was 53.6 (range 41 to 68) years, with a mean pain level of 6.1 (range 4 to 10) on the Visual Analogue Scale and a calcaneodynia score of 48.7 (range 33 to 66). Significant correlations were seen between several dynamic gait values and clinical scoring: cadence (rs = 0.56, p = .004), stance time (rs = -0.6, p = .002), center-of-pressure velocity (rs = 0.44, p = .046), and double support time (rs = 0.42, p = .042). No significant correlations were seen between any force plate gait analysis values and clinical scoring. In this study setting, dynamic gait analysis was able to identify clinically relevant correlations to plantar fasciitis disease severity that standard force plate measurements could not. Keywords: gait; gait analysis; heel pain; insole; plantar fasciopathy. Copyright © 2018 the American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved. Full text links |
| 64. | Predictors for secondary hip osteoarthritis after acetabular fractures-a pelvic registry studyInt Orthop. 2019 Sep;43(9):2167-2173. doi: 10.1007/s00264-018-4169-3. Epub 2018 Sep 29. AuthorsMika F Rollmann 1 , Jörg H Holstein 2 , Tim Pohlemann 2 , Steven C Herath 2 , Tina Histing 2 , Benedikt J Braun 2 , Hagen Schmal 3 , Guy Putzeys 4 , Ivan Marintschev 5 , Emin Aghayev 6 Affiliations
AbstractPurpose: Secondary hip osteoarthritis after acetabular fractures requiring total arthroplasty (THA) poses a huge burden on the affected patients as well as health systems. The present study aimed to assess risk factors associated with THA after acetabular fractures based on the data from the German Pelvic Trauma Registry. Methods: Retrospective analysis of 678 acetabular fracture cases without concomitant pelvic ring fracture treated and followed-up between January 2004 and May 2015 at six large trauma centres. Multivariate Cox regression analysis was performed assessing the association of patient/treatment characteristics with THA likelihood at an average follow-up of 2.7 years (range 0.4-9.5 years; SD 1.8 years). Results: Overall, the rate of secondary osteoarthritis was 19.8%. The likelihood for THA increased with 6% per age year (95% CI 1.04-1.09) and with 21% per millimetre subluxation (95%CI 1.09-1.33). This likelihood was 3.54 (95% CI 1.77-7.08) and 3.68 times (95% CI 1.87-7.47) higher if the posterior wall was involved and a contusion and/or impaction of the femoral head was present. Other covariates (sex, ISS, trauma type, AO/OTA and Letournel classification, initial displacement, surgical approach, intra-articular fragments, contusion and/or impaction to the acetabulum, reduction, intervention type, duration of surgery, soft tissue damage, residual fracture step/gap, and prevention of heterotopic ossifications) were not significantly associated (p > 0.15). Conclusions: Twenty percent of patients with acetabular fractures require THA. The associated risk factors are patient age, femoral head lesion/subluxation, and involvement of the posterior wall. The identified risk factors support previous research and should be minded when treatment of acetabular fractures is planned. Keywords: Acetabular fracture; Cox regression model; German pelvic trauma registry; Secondary hip osteoarthritis. Full text links |
| 65. | Effects of locally applied adipose tissue-derived microvascular fragments by thermoresponsive hydrogel on bone healingActa Biomater. 2018 Sep 1:77:201-211. doi: 10.1016/j.actbio.2018.07.029. Epub 2018 Jul 17. AuthorsM Orth 1 , M A B Altmeyer 2 , C Scheuer 3 , B J Braun 2 , J H Holstein 2 , D Eglin 4 , M D'Este 4 , T Histing 2 , M W Laschke 3 , T Pohlemann 5 , M D Menger 3 Affiliations
AbstractInsufficient vascularization is a major cause for the development of non-unions. To overcome this problem, adipose tissue-derived microvascular fragments (MVF) may serve as vascularization units. However, their application into bone defects needs a carrier system. Herein, we analyzed whether this is achieved by a thermoresponsive hydrogel (TRH). MVF were isolated from CD-1 mice and cultivated after incorporation into TRH, while non-incorporated MVF served as controls. Viability of MVF was assessed immunohistochemically over a 7-day period. Moreover, osteotomies were induced in femurs of CD-1 mice. The osteotomy gaps were filled with MVF-loaded TRH (TRH + MVF), unloaded TRH (TRH) or no material (control). Bone healing was evaluated 14 and 35 days postoperatively. MVF incorporated into TRH exhibited less apoptotic cells and showed a stable vessel morphology compared to controls. Micro-computed tomography revealed a reduced bone volume in TRH + MVF femurs. Histomorphometry showed less bone and more fibrous tissue after 35 days in TRH + MVF femurs compared to controls. Accordingly, TRH + MVF femurs exhibited a lower osseous bridging score and a reduced bending stiffness. Histology and Western blot analysis revealed an increased vascularization and CD31 expression, whereas vascular endothelial growth factor (VEGF) expression was reduced in TRH + MVF femurs. Furthermore, the callus of TRH + MVF femurs showed increased receptor activator of NF-κB ligand expression and higher numbers of osteoclasts. These findings indicate that TRH is an appropriate carrier system for MVF. Application of TRH + MVF increases the vascularization of bone defects. However, this impairs bone healing, most likely due to lower VEGF expression during the early course of bone healing. Statement of significance: In the present study we analyzed for the first time the in vivo performance of a thermoresponsive hydrogel (TRH) as a delivery system for bioactive microvascular fragments (MVF). We found that TRH represents an appropriate carrier for MVF as vascularization units and maintains their viability. Application of MVF-loaded TRH impaired bone formation in an established murine model of bone healing, although vascularization was improved. This unexpected outcome was most likely due to a reduced VEGF expression in the early phase bone healing. Keywords: Bone healing; Microvascular fragments; Thermoresponsive hydrogel; VEGF; Vascularization. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Full text links |
| 66. | Evaluation of strategies for the treatment of type B and C pelvic fractures: results from the German Pelvic Injury RegisterBone Joint J. 2018 Jul;100-B(7):973-983. doi: 10.1302/0301-620X.100B7.BJJ-2017-1377.R1. AuthorsH Schmal 1 , L Froberg 2 , M S Larsen 3 , N P Südkamp 4 , T Pohlemann 5 , E Aghayev 6 , K Goodwin Burri 7 Affiliations
Free article AbstractAims: The best method of treating unstable pelvic fractures that involve the obturator ring is still a matter for debate. This study compared three methods of treatment: nonoperative, isolated posterior fixation and combined anteroposterior stabilization. Patients and methods: The study used data from the German Pelvic Trauma Registry and compared patients undergoing conservative management (n = 2394), surgical treatment (n = 1345) and transpubic surgery, including posterior stabilization (n = 730) with isolated posterior osteosynthesis (n = 405) in non-complex Type B and C fractures that only involved the obturator ring anteriorly. Calculated odds ratios were adjusted for potential confounders. Outcome criteria were intraoperative and general short-term complications, the incidence of nerve injuries, and mortality. Results: Operative stabilization reduced mortality by 36% (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.42 to 0.98) but the incidence of complications was twice as high (OR 2.04, 95% CI 1.57 to 2.64). Mortality and the incidence of neurological deficits at discharge were no different after isolated posterior or combined anteroposterior fixation. However, the odds of both surgical (98%, OR 1.98, 95%CI 1.22 to 3.22) and general complications (43%, OR 1.43, 95% CI 1.02 to 2.00) were higher in the group with the more extensive surgery. Conclusion: Operative stabilization is recommended for non-complex unstable pelvic fractures. The need for anterior fixation of obturator ring fractures should, however, be considered critically. Cite this article: Bone Joint J 2018;100-B:973-83. Keywords: Anterior pelvic ring; Fixation; Logistic regression; Models; Osteosynthesis; Pelvic fracture; Registry; Treatment; Unstable. Full text links |
| 67. | C-arm fluoroscopy in orthopaedic surgical practiceEur J Orthop Surg Traumatol. 2018 Dec;28(8):1563-1568. doi: 10.1007/s00590-018-2234-7. Epub 2018 May 23. AuthorsIshaq Ojodu 1 , Ayodele Ogunsemoyin 2 , Sascha Hopp 3 4 , Tim Pohlemann 4 , Oluwole Ige 5 , Oluwaseun Akinola 2 Affiliations
AbstractThe use of C-arm fluoroscopy in intraoperative orthopaedic procedures has become an important tool in modern orthopaedic surgical practice. It enhances the technical proficiency of the surgeon in addition to reducing the morbidity and length of hospital stay of the patient. Despite the documented benefits of this device, there has been a growing concern about the increased radiation exposure to the surgical team. We therefore present the review of the literature on the usefulness of C-arm fluoroscopy, pitfalls in application of the machine as well as the harmful radiation effects and precautionary measures that need to be observed when using the C-arm fluoroscopy in orthopaedic surgical procedures. Keywords: C-arm; Exposure; Fluoroscopy; Orthopaedic; Practice; Radiation. Full text links |
| 68. | A Minimally Invasive Model to Analyze Endochondral Fracture Healing in Mice Under Standardized Biomechanical ConditionsJ Vis Exp. 2018 Mar 22:(133):57255. doi: 10.3791/57255. AuthorsTina Histing 1 , Philipp Bremer 2 , Mika F Rollmann 2 , Steven Herath 2 , Moritz Klein 2 , Tim Pohlemann 2 , Michael D Menger 3 , Tobias Fritz 2 Affiliations
AbstractBone healing models are necessary to analyze the complex mechanisms of fracture healing to improve clinical fracture treatment. During the last decade, an increased use of mouse models in orthopedic research was noted, most probably because mouse models offer a large number of genetically-modified strains and special antibodies for the analysis of molecular mechanisms of fracture healing. To control the biomechanical conditions, well-characterized osteosynthesis techniques are mandatory, also in mice. Here, we report on the design and use of a closed bone healing model to stabilize femur fractures in mice. The intramedullary screw, made of medical-grade stainless steel, provides through fracture compression an axial and rotational stability compared to the mostly used simple intramedullary pins, which show a complete lack of axial and rotational stability. The stability achieved by the intramedullary screw allows the analysis of endochondral healing. A large amount of callus tissue, received after stabilization with the screw, offers ideal conditions to harvest tissue for biochemical and molecular analyses. A further advantage of the use of the screw is the fact that the screw can be inserted into the femur with a minimally invasive technique without inducing damage to the soft tissue. In conclusion, the screw is a unique implant that can ideally be used in closed fracture healing models offering standardized biomechanical conditions. Full text links |
| 69. | Novel pathomorphologic classification of capsulo-articular lesions of the pubic symphysis in athletes to predict treatment and outcomeArch Orthop Trauma Surg. 2018 May;138(5):687-697. doi: 10.1007/s00402-018-2893-1. Epub 2018 Feb 7. AuthorsSascha Hopp 1 2 , Ishaq Ojodu 3 4 , Atul Jain 3 5 , Tobias Fritz 3 , Tim Pohlemann 3 , Jens Kelm 6 Affiliations
AbstractIntroduction: Radiographic abnormalities of the symphysis as well as the formation of accessory clefts, indicating injury at the rectus-adductor aponeurosis, reportedly relate to longstanding groin pain in athletes. However, yet, no systematic classification for clinical and scientific purposes exists. We aimed to (1) create a radiographic classification based on symphysography; (2) test intra- and interobserver reliability; (3) characterise clinical significance of the morphologic patterns by evaluating success of injection therapy. Patients and methods: We retrospectively reviewed symphysography, AP radiographs, and MRI of the pelvis from 70 consecutive competitive athletes, with chronic groin pain. Symphysographs were evaluated for intra- and interobserver variance using cohen's kappa statistics. Morphologic studies of the different contrast distribution patterns and their clinical and radiological correlation with symptom relief were investigated. All patients were followed up to evaluate immediate and long-term response to the initial therapeutic injection with steroid. Results: Four reproducible symphysographic patterns were identified: type 0, no changes; type 1, symphyseal disk degeneration; types 2a with unilateral clefts, bilateral clefts (2b), suprapubic clefts (2c); and type 3, with expanded or multidirectional clefts. Analysis revealed excellent intra (0.94)-and interobserver (0.90) reliability. Our findings showed that 78.6% of our patients had significant short-term improvement enabling early resumption of physiotherapy, only in types 1 and 2 (p = 0.001), while type 0 and 3 did not respond. At follow-up, only 21.8% had permanent pain relief. Regarding the detection of pathologic clefts with symphysography, sensitivity (88%) and specifity (77%) were superior to that of MRI. Conclusions: A reproducible symphysography-based classification of distinct morphologic patterns is proposed. It serves as a predictive tool for response to injection therapy in a select group of pathologic lesions. Complete recovery after injection can only be expected in a lesser percentage, as this might indicate surgical treatment for long-term non-responders. Keywords: Athletic pubalgia; Classification; Groin pain; Pubic symphysis; Symphysography. Full text links |
| 70. | The role of adipose-derived stem cells in a self-organizing 3D model with regard to human soft tissue healingMol Cell Biochem. 2018 Aug;445(1-2):195-210. doi: 10.1007/s11010-017-3265-9. Epub 2018 Jan 5. AuthorsMartin Oberringer 1 , Monika Bubel 2 , Martina Jennewein 2 , Silke Guthörl 2 , Tamara Morsch 2 , Sophie Bachmann 2 , Wolfgang Metzger 2 , Tim Pohlemann 2 Affiliations
AbstractThe clinical phenomenon of inadequate soft tissue healing still remains an important issue. The occurrence of chronic wounds is correlated to the life span, which is still increasing in western countries. Tissue engineering products containing adipose-derived stem cells are discussed as a promising therapeutic approach. Several studies confirmed the value of these cells for soft tissue healing improvement, suggesting a paracrine as well as a direct effect on vessel repair and angiogenesis. In an attempt to figure out specific effects of adipose-derived stem cells on dermal microvascular endothelial cells with respect to the different phases of soft tissue healing, we designed a 3D in vitro model on the basis of spheroids. Basic parameters like spheroid volume, cell numbers, and rate of apoptotic cells were determined in dependence on culture time, on different oxygen conditions and using mono- as well as co-cultures of both cell types. Furthermore we focused on gene expression and protein levels of interleukin-6, interleukin-8, monocyte chemoattractant protein-1, and vascular endothelial growth factor, which are discussed against the background of therapies for chronic wounds. The visualization of α-smooth muscle actin allowed the estimation of the function of adipose-derived stem cells as stabilizer for dermal microvascular endothelial cells. The results of the present 3D model underscore a paracrine effect of adipose-derived stem cells on microvessel repair during early hypoxic conditions, whereas a stabilizing effect occurs during a later phase of soft tissue healing, simultaneously to reoxygenation. Keywords: Adipose-derived stem cell; Co-culture; Hypoxia; Microvascular endothelial cell; Soft tissue healing; Wound. Full text links |
| 71. | Long-term pathological gait pattern changes after talus fractures - dynamic measurements with a new insoleInt Orthop. 2018 May;42(5):1075-1082. doi: 10.1007/s00264-017-3720-y. Epub 2018 Jan 2. AuthorsBenedikt J Braun 1 , Patrick Pelz 2 , Nils T Veith 2 , Mika Rollmann 2 , Moritz Klein 2 , Steven C Herath 2 , Jörg H Holstein 2 , Tim Pohlemann 2 Affiliations
AbstractPurpose: The aim of the current study was to describe long-term gait changes after talus fractures, identify patterns associated with poor outcome and discuss possible treatment options based on dynamic gait analysis. Methods: Twenty-seven patients were followed-up clinically and via gait analysis after talus fracture osteosynthesis. Continuous dynamic pedobarography with a gait analysis insole was performed on a standardized parcours consisting of different gait tasks and matched to the outcome. Results: Mean follow-up was 78.3 months (range 21-150), mean AOFAS and Olerud-Molander scores 66 (range 20-100) and 54 (range 15-100). Significant correlations between fracture classification and osteoarthritis (Hawkins: rs = 0.67 / Marti-Weber: rs = 0.5) as well as several gait differences between injured and healthy foot with correlations to outcome were seen: decreased step load-integral/maximum-load; associations between centre-of-pressure displacement and outcome as well as between temporospatial measures and outcome. Overall, pressure-distribution was lateralized in patients with subtalar joint injury (Δ: 0.5765 N/cm2, p = 0.0475). Conclusions: Talus fractures lead to chronic gait changes and restricted function. Dynamic pedobarography can identify patterns associated with poor results. The observed gait patterns suggest that changes can be addressed by physical therapy and customized orthoses to improve overall outcome. The presented insole and measurement protocol are immediately feasible as a diagnostic and rehabilitation aid. Keywords: Fracture; Gait analysis; Pedobarography; Talus. Full text links |
| 72. | Accidental Thumb Injection With an Epinephrine AutoinjectorDtsch Arztebl Int. 2017 Nov 24;114(47):804. doi: 10.3238/arztebl.2017.0804. AuthorsTobias Fritz, Tim Pohlemann, Moritz Klein
No abstract available Full text links |
| 73. | Dissociation of mono- and co-culture spheroids into single cells for subsequent flow cytometric analysisAnn Anat. 2018 Mar:216:1-8. doi: 10.1016/j.aanat.2017.10.002. Epub 2017 Nov 21. AuthorsUte Grässer 1 , Monika Bubel 2 , Daniela Sossong 3 , Martin Oberringer 4 , Tim Pohlemann 5 , Wolfgang Metzger 6 Affiliations
AbstractBackground: Spheroids are considered to reflect the natural organization of cells better than 2D cell cultures, but their analysis by flow cytometry requires dissociation into single cells. Methods: We established protocols for dissociation of mono- and co-culture spheroids consisting of human fibroblasts and human endothelial cells. Cell recovery rate and viability after dissociation were evaluated with hemocytometer and by flow cytometry. The diameter of cells and the amount of cell aggregates were quantified by Casy®-technology and the cellular composition was analyzed by flow cytometry. Results: Optimal dissociation conditions with low cell aggregation were determined by size, cultivation time and cellular composition of the spheroids. Smaller spheroids (10,000 cells) could be dissociated with Accutase®, whereas larger spheroids (50,000 cells) required more stringent dissociation conditions. The size of the cells decreased with increasing cultivation time. Cell recovery rate was dependent upon cellular composition and spheroid size. The highest cell recovery rate was found for co-culture spheroids. The highest cell viability was detected for dissociated fibroblast spheroids. A quantitative analysis of the cellular composition of dissociated co-culture spheroids was possible. Discussion: Spheroids can be successfully dissociated into singular cells for subsequent flow cytometric analysis. Dissociation conditions as well as cell recovery rate and cell viability depend on size, cultivation time and cellular composition of the spheroids. The observed decrease in cell size in spheroids over time might be responsible for the well-known time-dependent decrease in spheroid size. Keywords: Cell recovery rate; Cell viability; Co-culture; Dissociation; Endothelial cells; Fibroblasts; Spheroids. Copyright © 2017 Elsevier GmbH. All rights reserved. Full text links |
| 74. | Comparative Degradomics of Porcine and Human Wound Exudates Unravels Biomarker Candidates for Assessment of Wound Healing Progression in Trauma PatientsJ Invest Dermatol. 2018 Feb;138(2):413-422. doi: 10.1016/j.jid.2017.08.032. Epub 2017 Sep 9. AuthorsFabio Sabino 1 , Fabian E Egli 2 , Simonas Savickas 2 , Jörg Holstein 3 , Daniela Kaspar 4 , Mika Rollmann 3 , Jayachandran N Kizhakkedathu 5 , Tim Pohlemann 3 , Hans Smola 4 , Ulrich Auf dem Keller 6 Affiliations
Free article AbstractImpaired cutaneous wound healing is a major complication in elderly people and patients suffering from diabetes, the rate of which is rising in industrialized countries. Heterogeneity of clinical manifestations hampers effective molecular diagnostics and decisions for appropriate therapeutic regimens. Using a customized positional quantitative proteomics workflow, we have established a time-resolved proteome and N-terminome resource from wound exudates in a clinically relevant pig wound model that we exploited as a robust template to interpret a heterogeneous dataset from patients undergoing the same wound treatment. With zyxin, IQGA1, and HtrA1, this analysis and validation by targeted proteomics identified differential abundances and proteolytic processing of proteins of epidermal and dermal origin as prospective biomarker candidates for assessment of critical turning points in wound progression. Thus, we show the possibility of using a fine-tuned animal wound model to bridge the translational gap as a prerequisite for future extended clinical studies with large cohorts of individuals affected by healing impairments. Data are available via ProteomeXchange with identifier PXD006674. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved. Full text links |
| 75. | Mechanical and biological characterization of alkaline substituted orthophosphate bone substitutes containing meta- and diphosphatesBiomed Mater. 2017 Sep 25;12(5):055007. doi: 10.1088/1748-605X/aa7e80. AuthorsMoritz Klein 1 , Matthias W Laschke, Jörg H Holstein, Tina Histing, Tim Pohlemann, Michael D Menger, Patric Garcia Affiliation
AbstractDespite the growing knowledge on the mechanisms of fracture healing, bone defects often do not heal in a timely manner. Clinically, tricalcium phosphate (TCP) bone substitutes are used to fill bone defects and promote bone healing. However, the degradation rate of these implants is often too slow for sufficient bone replacement. The use of calcium phosphate material with the crystalline phase Ca10[K/Na](PO4)7 containing different amounts of di- and metaphosphates may overcome this problem, because these materials show an accelerated degradation. Therefore, we generated alkaline substituted Ca-P scaffolds with different amounts of ortho-, di- and metaphosphates. The degradation of these materials was analyzed in TRIS-HCl buffer solution in vitro. Moreover, we measured the compressive strength and porosity of the scaffolds by micro-CT analysis. The biocompatibility of the scaffolds was evaluated in vivo in the mouse dorsal skinfold chamber by means of intravital fluorescence microscopy and histology. We found that higher amounts of incorporated di- and metaphosphates increase the degradation rate and compressive strength of the scaffolds without inducing a stronger leukocytic inflammatory host tissue reaction after implantation. Histological analyses confirmed the good biocompatibility of the scaffolds containing di- and metaphosphates. In summary, this study demonstrates that the compressive strength and degradation rate of Ca-P scaffolds can be improved by incorporation of di- and metaphosphates without affecting their good biocompatibility. Hence, this material modification may be particularly beneficial for the treatment of metaphyseal bone defects in weight bearing locations. Full text links |
| 76. | Helping prometheus: liver protection in acute hemorrhagic shockAnn Transl Med. 2017 May;5(10):206. doi: 10.21037/atm.2017.03.109. AuthorsNils T Veith 1 , Tina Histing 1 , Michael D Menger 2 , Tim Pohlemann 1 , Thomas Tschernig 3 Affiliations
AbstractAcute hemorrhagic hypovolemic shock is caused by a significant high blood loss and leads to hemodynamic instability. The decrease in intravascular volume results in cellular hypoxia and finally in damage to organs such as the liver and the kidney. The liver plays a decisive role in the development or prevention of multiple organ failure after hemorrhagic shock. Despite the large number of experimental studies, the knowledge of pathophysiological mechanisms in the liver after hemorrhagic shock is incomplete. The aim of this mini review was to provide an overview of the pathophysiological changes in liver function after acute hemorrhagic shock and to address treatment options to improve liver perfusion. Keywords: Adrenomedullin; experimental treatment; hemorrhagic shock; intravital microscopy; liver perfusion. Conflict of interest statementConflicts of Interest: The authors have no conflicts of interest to declare. Full text links |
| 77. | Polytrauma in the elderly: a reviewEFORT Open Rev. 2017 Mar 13;1(5):146-151. doi: 10.1302/2058-5241.1.160002. eCollection 2016 May. AuthorsBenedikt Johannes Braun 1 , Jörg Holstein 1 , Tobias Fritz 1 , Nils Thomas Veith 1 , Steven Herath 1 , Philipp Mörsdorf 1 , Tim Pohlemann 1 Affiliation
AbstractAlthough the field of geriatric trauma is - ironically - young, care for the elderly trauma patient is increasingly recognised as an important challenge, considering the worldwide trend towards increasing longevity.Increasing age is associated with physiological changes and resulting comorbidities that present multiple challenges to the treating physician.Even though polytrauma is less likely with increasing age, lower-energy trauma can also result in life-threatening injuries due to the reduced physiological reserve.Mechanisms of injury and resulting injury patterns are markedly changed in the elderly population and new management strategies are needed. From initial triage to long-term rehabilitation, these patients require care that differs from the everyday standard.In the current review, the special requirements of this increasing patient population are reviewed and management options discussed. With the increase in orthogeriatrics as a speciality, the current status quo will almost certainly shift towards a more tailored treatment approach for the elderly patient. Further research expanding our current knowledge is needed to reduce the high morbidity and mortality rate. Cite this article: Braun BJ, Holstein J, Fritz T, Veith NT, Herath S, Mörsdorf P, Pohlemann T. Polytrauma in the elderly: a review. EFORT Open Rev 2016;1:146-151. DOI: 10.1302/2058-5241.1.160002. Keywords: comorbidities; elderly; orthogeriatrics; polytrauma. Conflict of interest statementConflict of Interest: None declared. Full text links |
| 78. | Weight-bearing recommendations after operative fracture treatment-fact or fiction? Gait results with and feasibility of a dynamic, continuous pedobarography insoleInt Orthop. 2017 Aug;41(8):1507-1512. doi: 10.1007/s00264-017-3481-7. Epub 2017 Apr 19. AuthorsBenedikt J Braun 1 , Nils T Veith 2 , Mika Rollmann 2 , Marcel Orth 2 , Tobias Fritz 2 , Steven C Herath 2 , Jörg H Holstein 2 , Tim Pohlemann 2 Affiliations
AbstractPurpose: Rehabilitation after lower-extremity fractures is based on the physicians' recommendation for non-, partial-, or full weight-bearing. Clinical studies rely on this assumption, but continuous compliance or objective loading rates are unknown. The purpose of this study was to determine the compliance to weight-bearing recommendations by introducing a novel, pedobarography system continuously registering postoperative ground forces into ankle, tibial shaft and proximal femur fracture aftercare and test its feasibility for this purpose. Methods: In this prospective, observational study, a continuously measuring pedobarography insole was placed in the patients shoe during the immediate post-operative aftercare after ankle, tibial shaft and intertrochanteric femur fractures. Weight-bearing was ordered as per the institutional standard and controlled by physical therapy. The insole was retrieved after a maximum of six weeks (28 days [range 5-42 days]). Non-compliance was defined as a failure to maintain, or reach the ordered weight-bearing within 30%. Results: Overall 30 patients were included in the study. Fourteen (47%) of the patients were compliant to the weight-bearing recommendations. Within two weeks after surgery patients deviated from the recommendation by over 50%. Sex, age and weight did not influence the performance (p > 0.05). Ankle fracture patients (partial weight-bearing) showed a significantly increased deviation from the recommendation (p = 0.01). Conclusions: Our study results show that, despite physical therapy training, weight-bearing compliance to recommended limits was low. Adherence to the partial weight-bearing task was further decreased over time. Uncontrolled weight-bearing recommendations should thus be viewed with caution and carefully considered as fiction. The presented insole is feasible to determine weight bearing continuously, could immediately help define real-time patient behaviour and establish realistic, individual weight-bearing recommendations. Keywords: Compliance; Gait analysis; Pedobarography; Weight-bearing. Full text links |
| 79. | Pelvic ring fractures in the elderly now and then - a pelvic registry studyArch Gerontol Geriatr. 2017 Jul:71:83-88. doi: 10.1016/j.archger.2017.03.007. Epub 2017 Mar 19. AuthorsMika F Rollmann 1 , Steven C Herath 2 , Florian Kirchhoff 2 , Benedikt J Braun 2 , Joerg H Holstein 2 , Tim Pohlemann 2 , Michael D Menger 3 , Tina Histing 2 Affiliations
AbstractObjectives: To analyze the changes in demographic data stratified for age, sex and type of injury of elderly patients suffering from pelvic ring fractures over a 22-year observation period. Design/setting: Data has been collected prospectively, multi-centrically in hospitals participating in the German Pelvic Trauma Registry. Patients: We analyzed the data of 5665 patients with an age ≥60years included in the German Pelvic Trauma Registry from 1991 to 2013. Key results: Over the 22-year study period the frequency of type A fractures decreased significantly from 84.8% to 43.9%, while type C and, in particular, type B fractures significantly increased from 7.0% and 8.2% to 14.3% and 41.8%. In patients between 60 and 70 years of age the frequency of type B and C fractures was higher compared to patients >70years. The proportion of female patients, who represent the majority of the cohort (75%), was stable over the entire observation period. Interestingly, type A fractures were found more frequently in females, while type B and C fractures were found more frequently in males. Conclusions: With the predicted demographic change and a shift toward more severe injury patterns (type B and C pelvic fractures) in the elderly population, trauma departments will need to develop specific surgical concepts for geriatric patients with pelvic ring fractures. Keywords: Elderly; Gender; Geriatric medicine; Pelvic ring fractures. Copyright © 2017 Elsevier B.V. All rights reserved. Full text links |
| 80. | Introduction of a computer-based method for automated planning of reduction paths under consideration of simulated muscular forcesInt J Comput Assist Radiol Surg. 2017 Aug;12(8):1369-1381. doi: 10.1007/s11548-017-1562-0. Epub 2017 Mar 20. AuthorsJan Buschbaum 1 , Rainer Fremd 2 , Tim Pohlemann 3 , Alexander Kristen 3 Affiliations
AbstractPurpose: Reduction is a crucial step in the surgical treatment of bone fractures. Finding an optimal path for restoring anatomical alignment is considered technically demanding because collisions as well as high forces caused by surrounding soft tissues can avoid desired reduction movements. The repetition of reduction movements leads to a trial-and-error process which causes a prolonged duration of surgery. By planning an appropriate reduction path-an optimal sequence of target-directed movements-these problems should be overcome. For this purpose, a computer-based method has been developed. Methods: Using the example of simple femoral shaft fractures, 3D models are generated out of CT images. A reposition algorithm aligns both fragments by reconstructing their broken edges. According to the criteria of a deduced planning strategy, a modified A*-algorithm searches collision-free route of minimal force from the dislocated into the computed target position. Muscular forces are considered using a musculoskeletal reduction model (OpenSim model), and bone collisions are detected by an appropriate method. Results: Five femoral SYNBONE models were broken into different fracture classification types and were automatically reduced from ten randomly selected displaced positions. Highest mean translational and rotational error for achieving target alignment is [Formula: see text] and [Formula: see text]. Mean value and standard deviation of occurring forces are [Formula: see text] for M. tensor fasciae latae and [Formula: see text] for M. semitendinosus over all trials. These pathways are precise, collision-free, required forces are minimized, and thus regarded as optimal paths. Conclusions: A novel method for planning reduction paths under consideration of collisions and muscular forces is introduced. The results deliver additional knowledge for an appropriate tactical reduction procedure and can provide a basis for further navigated or robotic-assisted developments. Keywords: Automated path planning; Computer-assisted fracture reduction; Femoral fractures; Guided surgery; Reduction paths. Full text links |
| 81. | Clinical outcome after alternative treatment of scaphoid fractures and nonunionsEur J Trauma Emerg Surg. 2018 Feb;44(1):113-118. doi: 10.1007/s00068-017-0773-y. Epub 2017 Feb 27. AuthorsA L Sander 1 2 , K Sommer 3 , D Schäf 3 , C Braun 4 , I Marzi 3 , T Pohlemann 5 , J Frank 3 Affiliations
AbstractPurpose: Achieving stable fixation of scaphoid fractures and nonunions continues to be a challenge. Compression screw fixation has been the current standard surgical procedure. However, in some cases, bone healing cannot be achieved and requires further revision. Recent series reintroduced volar plating as valid option for stable fixation. The aim of the study was to review clinical outcome of alternative scaphoid treatment. Methods: From 2011 to 2014, nine patients with scaphoid fracture were treated by Headless Compression Screw (HCS) and seven patients with scaphoid nonunion by HCS or volar mini condylar plate with bone graft. The average age was 34.4 years and the average time to follow-up was 19.3 months. From 1996 to 1998, 38 patients with scaphoid nonunion were treated using compression screw (S-group) or volar mini condylar plate (P-group) with bone graft. The average age was 39.6 years and the average time to follow-up was 26.2 months. Results: The union rate was 100%. For scaphoid fractures, the mean Modified Mayo Wrist Score (MMWS) was 94.1 and the DASH score 7.4. From 2011 to 2014, the MMWS was 87.9 and the DASH score 7 in scaphoid nonunions. In the period between 1996 and 1998, the MMWS was 67.2 in the P-group and 58.6 in the S-group, and the DASH score 16.8 and 28.2. Conclusions: Our study demonstrated that appropriate application of the HCS was able to produce very satisfactory results in scaphoid fractures and nonunions. In our opinion, however, the method of scaphoid plate osteosynthesis can achieve a higher degree of stability, particularly rotational stability, in case of multifragmentary avascular scaphoid nonunions. Keywords: 1,2-ICSRA; Compression screw; Mini condylar plate; Scaphoid fracture; Scaphoid nonunion. Full text links |
| 82. | [A new continuous gait analysis system for ankle fracture aftercare]Unfallchirurg. 2018 Apr;121(4):293-299. doi: 10.1007/s00113-017-0332-3. [Article in German] AuthorsB J Braun 1 , N T Veith 2 , S C Herath 2 , R Hell 2 , M Rollmann 2 , M Orth 2 , J H Holstein 2 , T Pohlemann 2 Affiliations
AbstractBackground: Correct aftercare following lower extremity fractures remains a controversial issue. Reliable, clinically applicable weight-bearing recommendations have not yet been defined. The aim of the current study was to establish a new gait analysis insole during physical therapy aftercare of ankle fractures to test patients' continuous, long-term compliance to partial weight-bearing restrictions and investigate whether patients can estimate their weight-bearing compliance. Materials and methods: The postoperative gait of 14 patients after operative treatment of Weber B-type ankle fractures was monitored continuously for six weeks (OpenGO, Moticon GmbH, Munich). All patients were instructed and trained by physical therapists on how to maintain partial weight-bearing for this time. Discontinuous (three, six and twelve weeks) clinical (patient questionnaire, visual analogue pain score [VAS]) and radiographic controls were performed. Results: Despite the set weight-bearing limits, individual ranges for overall weight-bearing (range 5-107% of the contralateral side) and patient activity (range 0-366 min/day) could be shown. A good correlation between weight-bearing and pain was seen (rs = -0.68; p = <0.0001). Patients significantly underestimated their weight-bearing time over the set limit (2.3 ± 1.4 min/day vs. real: 12.6 ± 5.9 min/day; p < 0.01). Conclusions: Standardized aftercare protocols and repeated training alone cannot ensure compliance to postoperative partial weight-bearing. Patients unconsciously increased weight-bearing based on their pain level. This study shows that new, individual and possibly technology-assisted weight-bearing regimes are needed. The introduced measuring device is feasible to monitor and steer patient weight-bearing during future studies. Keywords: Aftercare; Ankle; Fracture; Gait analysis; Pedobarography. Full text links |
| 83. | Evaluation of cell-surface interaction using a 3D spheroid cell culture model on artificial extracellular matricesMater Sci Eng C Mater Biol Appl. 2017 Apr 1:73:310-318. doi: 10.1016/j.msec.2016.12.087. Epub 2016 Dec 20. AuthorsWolfgang Metzger 1 , Sandra Rother 2 , Tim Pohlemann 3 , Stephanie Möller 4 , Matthias Schnabelrauch 4 , Vera Hintze 2 , Dieter Scharnweber 2 Affiliations
AbstractSince decades, cell-surface interactions are studied in 2D cell culture approaches, but cells organized in 3D (spheroids) reflect the normal situation of cells in tissues much better due to intense cell-cell-contacts. Accordingly, this study aimed to prove, if spheroids could be used to study cell-surface interaction. Spheroids consisting of fibroblasts and/or osteoblasts were seeded on artificial extracellular matrices. Here, non-sulfated hyaluronan as a biological relevant compound of the extracellular matrix was chemically sulfated to different extents and co-fibrillised with collagen. The changes of the spheroid diameters and the migration distance of outgrown cells after seeding on the matrices were used as parameters to evaluate cell-surface interaction quantitatively. Fibroblast-based spheroids reacted in the initial phase of adhesion with different spheroid sizes on the contact with the matrices. In contrast, the reaction of osteoblasts was more pronounced at later time points exhibiting a decrease of the size of the spheroids with increasing sulfation degree of the matrix. The migration of the cells was impaired by increasing sulfation degree, which might be caused by an increased expression of focal adhesion relevant proteins. In summary, spheroids can be used in cell-surface interaction studies and additional analytical tools could be implemented. Keywords: Cell-surface interaction; Glycosaminoglycans; Spheroid; Sulfated hyaluronan. Copyright © 2016 Elsevier B.V. All rights reserved. Full text links |
| 84. | [Surgery in the elderly]Chirurg. 2017 Feb;88(2):93-94. doi: 10.1007/s00104-016-0350-7. [Article in German] AuthorAffiliation
No abstract available Full text links |
| 85. | BMP-2-coated mineral coated microparticles improve bone repair in atrophic non-unionsEur Cell Mater. 2017 Jan 2:33:1-12. doi: 10.22203/eCM.v033a01. AuthorsM Orth 1 , N J Kruse, B J Braun, C Scheuer, J H Holstein, A Khalil, X Yu, W L Murphy, T Pohlemann, M W Laschke, M D Menger Affiliation
Free article AbstractAtrophic non-unions are a major clinical problem. Mineral coated microparticles (MCM) are electrolyte-coated hydroxyapatite particles that have been shown in vitro to bind growth factors electrostatically and enable a tuneable sustained release. Herein, we studied whether MCM can be used in vivo to apply Bone Morphogenetic Protein-2 (BMP-2) to improve bone repair of atrophic non-unions. For this purpose, atrophic non-unions were induced in femurs of CD-1 mice (n = 48). Animals either received BMP-2-coated MCM (MCM + BMP; n = 16), uncoated MCM (MCM; n = 16) or no MCM (NONE; n = 16). Bone healing was evaluated 2 and 10 weeks postoperatively by micro-computed tomographic (µCT), biomechanical, histomorphometric and immunohistochemical analyses. µCT revealed more bone volume with more highly mineralised bone in MCM + BMP femurs. Femurs of MCM + BMP animals showed a significantly higher bending stiffness compared to other groups. Histomorphometry further demonstrated that the callus of MCM + BMP femurs was larger and contained more bone and less fibrous tissue. After 10 weeks, 7 of 8 MCM + BMP femurs presented with complete osseous bridging, whereas NONE femurs exhibited a non-union rate of 100 %. Of interest, immunohistochemistry could not detect macrophages within the callus, indicating a good biocompatibility of MCM. In conclusion, the local application of BMP-2-coated MCM improved bone healing in a challenging murine non-union model and, thus, should be of clinical interest in the treatment of non-unions. Full text links |
| 86. | [Periprosthetic acetabular fractures in geriatric patients]Chirurg. 2017 Feb;88(2):105-109. doi: 10.1007/s00104-016-0340-9. [Article in German] AuthorsS C Herath 1 , M F R Rollmann 2 , T Histing 2 , J H Holstein 2 , T Pohlemann 2 Affiliations
AbstractPeriprosthetic acetabular fractures in geriatric patients are rare injuries; however, the incidence is increasing because of the current demographic developments. For diagnosis of periprosthetic acetabular fractures, conventional X‑ray images are regularly complemented by computed tomography (CT). For exclusion of loosening of the prosthesis more advanced techniques, such as single photon emission CT (SPECT/CT) are applied. In addition to classification of periprosthetic acetabular fractures by the traditional system of Letournel there are several other classification systems, which take into account the etiology of the fracture and the stability of the prosthesis. While, under certain circumstances conservative treatment of periprosthetic acetabular fractures is possible, operative treatment often requires extensive surgical procedures to restore the stability of the acetabulum as a support for the cup of the prosthesis. Besides the traditional techniques of acetabular osteosynthesis, special revision systems, augmentations and allografts are used for the reconstruction of periprosthetic acetabular fractures. To determine a therapeutic regimen patient-specific preconditions as well as fracture pattern and type of prosthesis need to be taken into account. In the literature there are several algorithms, which are aimed at supporting the attending physician in making the correct decision for the treatment of periprosthetic acetabular fractures. In cases of periprosthetic acetabular fractures even experienced surgeons are faced with great challenges. Thus, treatment should be carried out in specialized centers. Keywords: Acetabulum; Hip; Periprosthetic fracture; Prosthesis; Treatment. Full text links |
| 87. | Challenges in geriatric trauma careInnov Surg Sci. 2016 Dec 22;1(2):47-48. doi: 10.1515/iss-2016-0201. eCollection 2016 Dec. AuthorsTim Pohlemann 1 , Tina Histing 2 Affiliations
No abstract available Full text links |
| 88. | An Intramedullary Locking Nail for Standardized Fixation of Femur Osteotomies to Analyze Normal and Defective Bone Healing in MiceJ Vis Exp. 2016 Nov 13:(117):54472. doi: 10.3791/54472. AuthorsTina Histing 1 , Michael D Menger 2 , Tim Pohlemann 3 , Romano Matthys 4 , Tobias Fritz 3 , Patric Garcia 3 , Moritz Klein 3 Affiliations
AbstractBone healing models are essential to the development of new therapeutic strategies for clinical fracture treatment. Furthermore, mouse models are becoming more commonly used in trauma research. They offer a large number of mutant strains and antibodies for the analysis of the molecular mechanisms behind the highly differentiated process of bone healing. To control the biomechanical environment, standardized and well-characterized osteosynthesis techniques are mandatory in mice. Here, we report on the design and use of an intramedullary nail to stabilize open femur osteotomies in mice. The nail, made of medical-grade stainless steel, provides high axial and rotational stiffness. The implant further allows the creation of defined, constant osteotomy gap sizes from 0.00 mm to 2.00 mm. Intramedullary locking nail stabilization of femur osteotomies with gap sizes of 0.00 mm and 0.25 mm result in adequate bone healing through endochondral and intramembranous ossification. Stabilization of femur osteotomies with a gap size of 2.00 mm results in atrophic non-union. Thus, the intramedullary locking nail can be used in healing and non-healing models. A further advantage of the use of the nail compared to other open bone healing models is the possibility to adequately fix bone substitutes and scaffolds in order to study the process of osseous integration. A disadvantage of the use of the intramedullary nail is the more invasive surgical procedure, inherent to all open procedures compared to closed models. A further disadvantage may be the induction of some damage to the intramedullary cavity, inherent to all intramedullary stabilization techniques compared to extramedullary stabilization procedures. Full text links |
| 89. | Predictive value of clinical scoring and simplified gait analysis for acetabulum fracturesJ Surg Res. 2016 Dec;206(2):405-410. doi: 10.1016/j.jss.2016.08.061. Epub 2016 Aug 23. AuthorsBenedikt J Braun 1 , Julian Wrona 2 , Nils T Veith 2 , Mika Rollman 2 , Marcel Orth 2 , Steven C Herath 2 , Jörg H Holstein 2 , Tim Pohlemann 2 Affiliations
AbstractBackground: Fractures of the acetabulum show a high, long-term complication rate. The aim of the present study was to determine the predictive value of clinical scoring and standardized, simplified gait analysis on the outcome after these fractures. Methods: Forty-one patients with acetabular fractures treated between 2008 and 2013 and available, standardized video recorded aftercare were identified from a prospective database. A visual gait score was used to determine the patients walking abilities 6-m postoperatively. Clinical (Merle d'Aubigne and Postel score, visual analogue scale pain, EQ5d) and radiological scoring (Kellgren-Lawrence score, postoperative computed tomography, and Matta classification) were used to perform correlation and multivariate regression analysis. Results: The average patient age was 48 y (range, 15-82 y), six female patients were included in the study. Mean follow-up was 1.6 y (range, 1-2 y). Moderate correlation between the gait score and outcome (versus EQ5d: rs = 0.477; versus Merle d'Aubigne: rs = 0.444; versus Kellgren-Lawrence: rs = -0.533), as well as high correlation between the Merle d'Aubigne score and outcome were seen (versus EQ5d: rs = 0.575; versus Merle d'Aubigne: rs = 0.776; versus Kellgren-Lawrence: rs = -0.419). Using a multivariate regression model, the 6 m gait score (B = -0.299; P < 0.05) and early osteoarthritis development (B = 1.026; P < 0.05) were determined as predictors of final osteoarthritis. A good fit of the regression model was seen (R2 = 904). Conclusions: Easy and available clinical scoring (gait score/Merle d'Aubigne) can predict short-term radiological and functional outcome after acetabular fractures with sufficient accuracy. Decisions on further treatment and interventions could be based on simplified gait analysis. Keywords: Acetabular fracture; Clinical scoring; Gait analysis. Copyright © 2016 Elsevier Inc. All rights reserved. Full text links |
| 90. | Blood loss in pelvic ring fractures: CT-based estimationAnn Transl Med. 2016 Oct;4(19):366. doi: 10.21037/atm.2016.08.39. AuthorsNils T Veith 1 , Moritz Klein 1 , Daniel Köhler 1 , Thomas Tschernig 2 , Jörg Holstein 1 , Philipp Mörsdorf 1 , Tim Pohlemann 1 , Benedikt J Braun 1 Affiliations
AbstractBackground: The main cause of mortality after pelvic ring fractures is the acute haemorrhagic shock. The aim of the study was to estimate blood loss using CT and to correlate estimated blood loss to the mortality. Methods: A retrospective analysis of 42 patients with AO/OTA C-type pelvic ring fractures was performed. In total 29 AO/OTA C1-type, 4 C2-type and 9 C3-type fractures were analysed. A CT-volumetric analysis was developed to estimate the early blood loss in the different compartments. The results were correlated to the mortality of the patients. Results: Significant increases in interstitial free blood volume (392±502.8 vs. 888±663; P<0.05) and total blood loss (476±535 vs. 1,005±649; P<0.05) were seen when comparing C1 to C3-type fractures. Early blood loss significantly correlated to mortality. No significant difference was seen between all groups with respect to systolic blood pressure, haemoglobin concentration and the Injury Severity Score (ISS). Conclusions: In pelvic ring fractures the CT-estimated blood loss correlates to mortality. Keywords: Pelvic ring fractures; blood loss; haemorrhagic shock; volumetric CT. Conflict of interest statementThe authors have no conflicts of interest to declare. Full text links |
| 91. | [Traumatic hip dislocation in a 6-year-old male child: Seldom but demanding]Unfallchirurg. 2017 Apr;120(4):350-354. doi: 10.1007/s00113-016-0268-z. [Article in German] AuthorsP Mörsdorf 1 , A Lauer 2 , T Histing 1 , T Pohlemann 1 , M Burkhardt 3 Affiliations
AbstractTraumatic hip dislocations in children are not frequent but constitute true emergencies. They require urgent reduction because of the risk of consecutive avascular necrosis of the femoral head. We report a 6-year-old boy with traumatic posterior hip dislocation on a vacation abroad. After closed reduction the day of the accident, a hip spica cast was applied and the patient was transferred home. Once home, X‑ray and CT diagnostics were completed by MRI. In future, long-term clinical and radiological investigations for avascular necrosis and growth disorders, as well as thoroughly informing the parents, should be mandatory. Keywords: Childhood; Problems and complications; Traumatic hip dislocation; Treatment. Full text links |
| 92. | Does the implant make the difference ? - Prospective comparison of two different proximal femur nailsActa Orthop Belg. 2016 Aug;82(2):319-331. AuthorsS Hopp, R Wirbel, I Ojodu, A Pizanis, T Pohlemann, J Fleischer
AbstractThe aim of this study was to compare two proximal femur nails with regard to the complication rate and midterm clinical outcome : the InterTAN nail (ITN) versus the third generation gamma nail (GN). 78 patients older than 60 years with an unstable intertrochanteric femoral fracture (AO/OTA 31 A2/A3) were randomised over a 20 month period into either ITN (n = 39) or GN (n = 39). The outcomes of interest were the perioperative implant-related complications and the functional status (Harris Hip Score) at 6 months postoperatively. In 14 of the ITN and in two of the GN procedures the surgeons rated the implant as cumbersome (p = 0.002). Functional outcome and complication rate did not differ between both groups. The mechanical failure correlated with the positioning of the lag screw independent on the used implant. The surgeon's technique (closed reduction, positioning of lag screw) and not implant configuration, is of crucial importance in achieving successful outcome. |
| 93. | [Salvage procedure for painful proximalisation of the 1st metacarpal after trapeziectomy using the Mini TightRope®]Handchir Mikrochir Plast Chir. 2016 Aug;48(5):300-5. doi: 10.1055/s-0042-113774. Epub 2016 Aug 31. [Article in German] AuthorsB J Braun 1 , N T Veith 1 , F S Frueh 2 , M Klein 1 , W Knopp 1 , T Pohlemann 1 Affiliations
AbstractPurpose: This study analyses our results after revision surgery for failed trapezectomy and suspension arthroplasty with painful proximalisation of the 1(st) metacarpal using the Mini TightRope(®). Patients and methods: In a prospective observational study, 5 patients (4 women and 1 man) with an average age of 62 years were treated with the Mini TightRope(®) for revision of a failed Epping arthroplasty with painful proximalisation of the first ray. The mean time between initial surgery and revision was 23.1 (12.5-31.5) months; the mean follow-up was 25±7.7 (12-32) months. The pain level (visual analogue scale - VAS), pinch grip, and qDASH score were evaluated preoperatively and postoperatively. In addition, the Conolly score was used postoperatively. Directly after surgery and at the last follow-up exam, the degree of proximalisation of the first metacarpal was measured radiologically. Results: At the last follow-up, there was significant mean pain relief during everyday stress, from 5.2 preoperatively to 1.6 (p<0.01) postoperatively, and a significant increase in pinch grip, from 0.5 kg to 3 kg (p<0.01). qDASH improved significantly, from 54 to 20 (p<0.001). The Conolly score showed 2 good and 3 fair results. Renewed proximalisation could not be entirely prevented, but was limited to an average of 2 mm. Conclusion: Mini TightRope(®) revision surgery after failed trapezectomy and suspension arthroplasty showes good results with significant pain reduction and gain of function. Renewed proximalisation of the first ray cannot be completely avoided. © Georg Thieme Verlag KG Stuttgart · New York. Comment in
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| 94. | Penetrating Thoracic Trauma Patients with Gross Physiological Derangement: A Responsibility for the General Surgeon in the Absence of Trauma or Cardiothoracic Surgeon?World J Surg. 2017 Jan;41(1):170-175. doi: 10.1007/s00268-016-3703-y. AuthorsDietrich Doll 1 2 , Markus Eichler 2 , Pantelis Vassiliu 3 , Kenneth Boffard 4 , Tim Pohlemann 5 , Elias Degiannis 1 4 Affiliations
AbstractBackground: Penetrating trauma is becoming increasingly common in parts of the world where previously it was rare. At the same time, general surgeons and surgical trainees are becoming more specialized, and less comfortable operating within areas beyond their zone of specialization. Objective: The purpose of this manuscript is to assess the technical difficulties encountered in operating on patients who have sustained penetrating trauma, and to prove to general surgeons that the technical skills and techniques required are no different to those required for abdominal surgery, and do not require additional dexterity. Methods: This prospective study was conducted in an Academic Trauma unit over a 3-year period. All patients who were operated upon for penetrating thoracic trauma were included in the study. The pre-operative management, techniques of surgical repair and the outcome were assessed. Results: One hundred and forty-five patients were included in the study over a 3-year period. There were 97 patients with stab wounds, 47 with gunshot wounds and 1 patient with an injury from an angle grinder. Mortality was six times greater in those patients with gunshot wounds, than those with stab wounds. Several patients had multiple thoracic organ injuries. There were 57 patients who were operated upon for thoracic vessel injury. There was a 3.5 % mortality overall. Eighty-eight patients sustained pulmonary injury with a 7 % mortality, and they were managed mainly by simply repair, tractotomy or stapled partial non-anatomical lobectomy. Of the 39 patients with cardiac trauma, there was 17 % mortality, and all cases were managed by simple repair. There were 5 patients with an oesophageal injury of whom 3 died (mortality of 60 %). Twenty-four patients had thoraco-abdominal injuries with 30 % mortality. Conclusion: Most of the injuries in the chest can be managed by simple procedures to control life-threatening bleeding. The techniques required are similar to those taught to and are practiced comfortably by general surgeons used to work in the abdominal cavity. We encourage the general surgeon who receives a grossly unstable patient with penetrating thoracic trauma to operate, instead of adding risk to the patient's physiology by a transfer to cardio-thoracic or dedicated trauma units. Full text links |
| 95. | Surgical treatment of pelvic ring fractures in the elderly now and then: a pelvic registry studyAging Clin Exp Res. 2017 Aug;29(4):639-646. doi: 10.1007/s40520-016-0612-8. Epub 2016 Aug 19. AuthorsMika F Rollmann 1 , Steven C Herath 2 , Joerg H Holstein 2 , Tim Pohlemann 2 , Michael D Menger 3 , Tina Histing 2 Affiliations
AbstractBackground: With the demographic change, the treatment of elderly patients has become a major issue for health systems worldwide. Aims: The aim of this study was to analyze the change in the rate of surgical treatment of pelvic ring fractures in patients with an age of ≥60 years over a 22-year period depending on fracture type, age and sex. Methods: Data of 5665 patients with an age of ≥60 years, who were treated for pelvic ring fractures from 1991 to 2013 in one of 31 hospitals participating in the German Pelvic Trauma Registry, were included. The registry is divided into four time periods: t 1 = 1991-1993, t 2 = 1997-2000, t 3 = 2001-2008 and t 4 = 2009-2013. Data had been collected prospectively and was analyzed retrospectively, stratified for age and sex of the patients as well as type of fracture and mode of therapy (surgical vs. conservative). Results: There was a significant increase (p < 0.05) in the overall rate of surgical treatment. Nonetheless, during all time periods patients with an age of >70 years were significantly less frequently surgically treated compared to 60- to 70-year-olds. Regardless of the fracture type, the rate of surgical treatment was significantly higher (p < 0.05) in male compared to female patients during t 1. While this difference persisted for type A and type B fractures, the frequency of surgical treatment of type C fractures approximated in males and females. Conclusions: The present data indicate that the rate of surgical treatment of pelvic ring fractures in elderly patients has significantly increased over the 22-year period. Nonetheless, older patients (>70 years) as well as female patients are still less frequently surgically treated. Keywords: Conservative; Elderly; Gender; Pelvic fractures; Surgery; Treatment. Full text links |
| 96. | [Midterm Results for Quality of Life After Surgical Treatment of Moore Type V Fractures of the Tibial Plateau]Z Orthop Unfall. 2016 Oct;154(5):513-520. doi: 10.1055/s-0042-106905. Epub 2016 Jul 1. [Article in German] AuthorsR Wirbel 1 , A Weber 1 , J Heinzmann 2 , C Meyer 3 , T Pohlemann 2 Affiliations
AbstractBackground: Dislocation fractures of the tibial plateau often lead to functional restrictions and subjective complaints from the patients. Besides functional and radiological results, criteria to determine the quality of life are of increasing importance. Intermediate term restriction in quality of life was evaluated and correlated with objective radiological results in patients with Moore type V dislocation fracture of the tibial plateau. Patients and Methods: From 2003 to 2012, a multicentre retrospective cohort study in three hospitals was used to register 36 patients with 38 Moore type V dislocation fractures of the tibial plateau. The injury mechanism, the surgical treatment (one step or two step surgery, single or double plate fixation) the complication rate, the radiological result (Kellgren/Lawrence osteoarthritis score, loss of reduction, secondary deviation of the axis) after a mean follow-up of 37 months, and the quality of life (pain and function by NRS, IKDC form, EQ 5D score) after a mean follow-up of 68 months (range, 15-128 months), were analysed. Results: The mean age of the 27 men and the 9 women was 50.8 years. There were 30 cases of high impact injury. An external fixator was used for primary fracture stabilisation in 24 knees; definitive internal fixation was performed in a second step. Internal fixation using a single plate was used in 12 knees, and double plate fixation in 25 knees; one patient was treated definitively with an external fixator. Early complications (3 × infection, 2 × compartment syndrome, 4 × implant failure) were seen in 21.1 % of patients; all could be cured surgically. The function of the affected knee joint gave a mean NRS of 4.53; the IKDC score was 50.46, and the EQ 5D 7.47. Only two patients (5 %) were free of pain, 27 (75 %) reported mild to moderate pain, and 7 patients (20 %) reported severe pain. Four patients are retired or have applied for a pension. Altogether, the quality of life was calculated as being 44 % of the initial value before the injury. Four patients required an endoprosthetic replacement at an early stage, after an average of 6 months. Signs of osteoarthritis (Kellgren/Lawrence > I) were seen in 32 of the remaining 33 fractures; 19 of these exhibited distinct signs of osteoarthritis (Kellgren/Lawrence III, IV). Loss of reduction (≥ 2 mm) was seen in 13 (34.2 %) and deviation of axis (> 10°) in 3 patients (7.8 %). There was no relation to the surgical strategy. However, there was a correlation between the subjective assessments of the quality of life and the radiological results. Conclusion: Moore type V dislocation fractures of the tibial plateau are severe knee injuries resulting in a distinct reduction in quality of life in the intermediate term. There is a correlation between the subjective assessments and the objective radiological results. Therefore, the congruency of the articular surface and the axis have to be reconstructed as precisely as possible when repairing fractures of the tibial plateau. Georg Thieme Verlag KG Stuttgart · New York. Full text links |
| 97. | [Talus Fractures - an Update]Zentralbl Chir. 2017 Apr;142(2):189-193. doi: 10.1055/s-0042-107950. Epub 2016 Jun 23. [Article in German] AuthorsN Veith 1 , B Braun 1 , M Hell 1 , M T Klein 1 , T Tschernig 2 , P Mörsdorf 1 , J H Holstein 1 , T Pohlemann 1 Affiliations
AbstractBackground: Talus fractures are rare and often result from axial trauma. As most of the talus surface is covered by cartilage, the blood supply is limited. Thus talus fractures are seen as one of the most severe fractures and often lead to significant long-term complications. Several studies suggest that the initial fracture classification can lead to correct treatment and that this can influence the long-term outcome. The aim of the current study was to investigate the importance of the initial fracture classification in respect to the radiological outcome in a large patient cohort. Patients and Methods: Over a span of 12 years, 61 patients with talus fractures were treated at our institution. Overall 45 patients were available for a retrospective analysis. Correlation analysis was performed between the initial fracture severity and the radiological outcome. Results: The average follow-up was 17.3 months (range 6-68). Significant correlations were found between the Marti-Weber Classification and Bargon Score (rs = 0.78; p < 0.0001), as well as between the Hawkins Classification and the Bargon Score (rs = 0.80; p < 0.0001). Conclusions: Precise prediction of the expected radiological outcome of talar neck and body fractures is possible through the initial fracture classification alone. Computed tomography is the accepted standard to determine the exact diagnosis and extent of injury. Georg Thieme Verlag KG Stuttgart · New York. Full text links |
| 98. | [Influence of the pelvic trauma registry of the DGU on treatment of pelvic ring fractures]Unfallchirurg. 2016 Jun;119(6):475-81. doi: 10.1007/s00113-016-0168-2. [Article in German] AuthorsJ H Holstein 1 , F M Stuby 2 , S C Herath 3 , U Culemann 4 , E Aghayev 5 , T Pohlemann 3 Affiliations
Free article AbstractFractures of the pelvic ring are comparatively rare with an incidence of 2-8 % of all fractures depending on the study in question. The severity of pelvic ring fractures can be very different ranging from simple and mostly "harmless" type A fractures up to life-threatening complex type C fractures. Although it was previously postulated that high-energy trauma was necessary to induce a pelvic ring fracture, over the past decades it became more and more evident, not least from data in the pelvic trauma registry of the German Society for Trauma Surgery (DGU), that low-energy minor trauma can also cause pelvic ring fractures of osteoporotic bone and in a rapidly increasing population of geriatric patients insufficiency fractures of the pelvic ring are nowadays observed with no preceding trauma.Even in large trauma centers the number of patients with pelvic ring fractures is mostly insufficient to perform valid and sufficiently powerful monocentric studies on epidemiological, diagnostic or therapeutic issues. For this reason, in 1991 the first and still the only registry worldwide for the documentation and evaluation of pelvic ring fractures was introduced by the Working Group Pelvis (AG Becken) of the DGU. Originally, the main objectives of the documentation were epidemiological and diagnostic issues; however, in the course of time it developed into an increasingly expanding dataset with comprehensive parameters on injury patterns, operative and conservative therapy regimens and short-term and long-term outcome of patients. Originally starting with 10 institutions, in the meantime more than 30 hospitals in Germany and other European countries participate in the documentation of data. In the third phase of the registry alone, which was started in 2004, data from approximately 15,000 patients with pelvic ring and acetabular fractures were documented. In addition to the scientific impact of the pelvic trauma registry, which is reflected in the numerous national and international publications, the dramatically changing epidemiology of pelvic ring fractures, further developments in diagnostics and the changes in operative procedures over time could be demonstrated. Last but not least the now well-established diagnostic and therapeutic algorithms for pelvic ring fractures, which could be derived from the information collated in registry studies, reflect the clinical impact of the registry. Keywords: Diagnostics algorithms; Epidemiology; Pelvic fracture; Registry; Therapy algorithms. Full text links |
| 99. | Obesity does not affect the healing of femur fractures in miceInjury. 2016 Jul;47(7):1435-44. doi: 10.1016/j.injury.2016.04.030. Epub 2016 Apr 23. AuthorsT Histing 1 , A Andonyan 2 , M Klein 2 , C Scheuer 3 , D Stenger 2 , J H Holstein 2 , N T Veith 2 , T Pohlemann 2 , M D Menger 3 Affiliations
AbstractObesity is reported to be both protective and deleterious to bone. Lipotoxicity and inflammation might be responsible for bone loss through inhibition of osteoblasts and activation of osteoclasts. However, little is known whether obesity affects the process of fracture healing. Therefore, we studied the effect of high fat diet-induced (HFD) obesity on callus formation and bone remodelling in a closed femur fracture model in mice. Thirty-one mice were fed a diet containing 60kJ% fat (HFD) for a total of 20 weeks before fracture and during the entire postoperative observation period. Control mice (n=31) received a standard diet containing 10kJ% fat. Healing was analyzed using micro-CT, biomechanical, histomorphometrical, immunohistochemical, serum and protein biochemical analysis at 2 and 4 weeks after fracture. HFD-fed mice showed a higher body weight and increased serum concentrations of leptin and interleukin-6 compared to controls. Within the callus tissue Western blot analyses revealed a higher expression of transcription factor peroxisome proliferator-activated receptor y (PPARy) and a reduced expression of runt-related transcription factor 2 (RUNX2) and bone morphogenetic protein (BMP)-4. However, obesity did not affect the expression of BMP-2 and did not influence the receptor activator of nuclear factor κB (RANK)/RANK ligand/osteoprotegerin (OPG) pathway during fracture healing. Although the bones of HFD-fed animals showed an increased number of adipocytes within the bone marrow, HFD did not increase callus adiposity. In addition, radiological and histomorphometric analysis could also not detect significant differences in bone formation between HFD-fed animals and controls. Accordingly, HFD did not affect bending stiffness after 2 and 4 weeks of healing. These findings indicate that obesity does not affect femur fracture healing in mice. Keywords: Bone formation; Bone remodelling; Callus adiposity; Fracture healing; Obesity. Copyright © 2016 Elsevier Ltd. All rights reserved. Full text links |
| 100. | Two- and three-dimensional co-culture models of soft tissue healing: pericyte-endothelial cell interactionCell Tissue Res. 2016 Aug;365(2):279-93. doi: 10.1007/s00441-016-2391-0. Epub 2016 Mar 30. AuthorsMartina Jennewein 1 , Monika Bubel 1 , Silke Guthörl 1 , Wolfgang Metzger 1 , Martin Weigert 1 , Tim Pohlemann 1 , Martin Oberringer 2 Affiliations
AbstractThe demographic change in western countries towards an older population is being shadowed by an increased appearance of chronic diseases influencing soft tissue healing in a negative manner. Although various promising therapeutic approaches are available for treating chronic wounds, no in vitro model exists that successfully allows the analysis of interacting cells and of the effect of therapeutic drugs within a wound. Granulation tissue assures wound stability, neo-angiogenesis and revascularization finally leading to functional soft tissue repair. As one of the first steps in developing a model for human granulation tissue, we examined microvascular endothelial cells and pericytes in conventional 2D and in 3D spheroid co-cultures. We determined which parameters could be used in a standardized manner and whether the cultures were responsive to hypoxia and to erythropoietin supplementation. The read-out parameters of cell migration, cell density, rate of apoptotic cells, spatial cell distribution in the spheroid and spheroid volume were shown to be excellent analytic measures. In addition, quantification of hypoxia-related genes identified a total of 13 genes that were up-regulated in spheroids after hypoxia. As these parameters delivered reliable results in the present approach and as the general morphological distribution of pericytes and endothelial cells within the spheroid occurred in a typical manner, we believe that this basic in vitro model will serve for the future study of diverse aspects of soft tissue healing. Keywords: Granulation tissue; Hypoxia; Microvascular endothelial cells; Pericytes; Wound healing. Full text links |
| 101. | Effect of Stabilization on the Healing Process of Femur Fractures in Aged MiceJ Invest Surg. 2016 Aug;29(4):202-8. doi: 10.3109/08941939.2015.1127448. Epub 2016 Feb 18. AuthorsT Histing 1 , K Heerschop 1 , M Klein 1 , C Scheuer 2 , D Stenger 1 , S C Herath 1 , T Pohlemann 1 , M D Menger 2 Affiliations
AbstractBackground: The influence of mechanical stability on fracture healing has previously been studied in adult mice, but is poorly understood in aged animals. Therefore, we herein studied the effect of stabilization on the healing process of femur fractures in aged mice. Methods: Twenty-four 18-month-old CD-1 mice were stabilized after midshaft fracture of the femur with an intramedullary screw. In another 24 18-month-old mice, the femur fractures were left unstabilized. Bone healing was studied by radiological, biomechanical, histomorphometric, and protein expression analyses. Results: After 2 and 5 weeks of healing, the callus of nonstabilized fractures compared to stabilized fractures was significantly larger, containing a significantly smaller amount of osseous tissue and a higher amount of cartilaginous tissue. This was associated with a significantly lower biomechanical stiffness during the early phase of healing. However, during the late phase of fracture healing both nonstabilized and stabilized fractures showed a biomechanical stiffness of ∼40%. Of interest, Western blot analyses of callus tissue demonstrated that the expression of proteins related to angiogenesis, bone formation and remodeling, i.e. VEGF, CYR61, BMP-2, BMP-4, Col-2, Col-10, RANKL, OPG, did not differ between nonstabilized and stabilized fractures. Conclusion: Nonstabilized fractures in aged mice show delayed healing and remodeling. This is not caused by an altered protein expression in the callus but rather by the excessive interfragmentary movements. Keywords: aging; bone remodeling; fracture; mechanical stability; nonstabilization; stabilization. Full text links |
| 102. | Osteogenic differentiation of immature osteoblasts: Interplay of cell culture media and supplementsBiotech Histochem. 2016;91(3):161-9. doi: 10.3109/10520295.2015.1110254. Epub 2016 Jan 21. AuthorsA Brauer 1 , T Pohlemann 1 , W Metzger 1 Affiliation
AbstractDifferentiation of immature osteoblasts to mature osteoblasts in vitro initially was induced by supplementing the medium with β-gylcerophosphate and dexamethasone. Later, ascorbic acid, vitamin D3, vitamin K3 and TGFβ1 were used in varying concentrations as supplements to generate a mature osteoblast phenotype. We tested the effects of several combinations of cell culture media, seeding protocols and osteogenic supplements on osteogenic differentiation of human primary osteoblasts. Osteogenic differentiation was analyzed by staining alkaline phosphatase (ALP) with 5-bromo-4-chloro-3-indolyl-phosphate/nitro blue tetrazolium (BCIP/NBT) and by von Kossa staining of deposited calcium phosphate. The combinations of culture media and supplements significantly influenced osteogenic differentiation, but the seeding protocol did not. Staining of ALP and calcium phosphate could be achieved only if our own mix of osteogenic supplements was used in combination with Dulbecco's modified Eagle medium or if a commercial mix of osteogenic supplements was used in combination with osteoblast growth medium. Especially for von Kossa, we observed great variations in the staining intensity. Because osteogenic differentiation is a complex process, the origin of the osteoblasts, cell culture media and osteogenic supplements should be established by preliminary experiments to achieve optimal differentiation. Staining of ALP or deposited calcium phosphate should be supplemented with qRT-PCR studies to learn more about the influence of specific supplements on osteogenic markers. Keywords: alkaline; cell culture; culture media; human; osteoblasts; osteogenic differentiation; osteogenic supplements; phosphatase; von Kossa staining. Full text links |
| 103. | [Saw Injuries to the Hand - Epidemiological Aspects]Zentralbl Chir. 2017 Apr;142(2):194-198. doi: 10.1055/s-0041-107435. Epub 2015 Dec 17. [Article in German] AuthorsN T Veith 1 , B Braun 1 , T Fritz 1 , T Pohlemann 1 , T Tschernig 2 , R Ziegler 1 , P Mörsdorf 1 , W Knopp 1 Affiliations
AbstractBackground: No current studies regarding saw injuries have been published in German literature for quite some time. Despite awareness measures and safety instructions, saw accidents along with crush injuries are the most common causes of severe hand injuries. Approximately 12,000 circular saw injuries occur in Germany each year. Since professional providers have increased prices due to the rising energy costs and a wide range of different home appliance saws are available, increasing use has been made of portable circular saws in the do-it-yourself market sector. Patients and methods: At our hospital, we evaluated the data of 51 male patients with saw injuries. The present study investigated factors that may contribute to accidents involving saws. Results: 80 % of the accidents occurred at home, usually on weekends or after work. 51 % of the accidents happened while patients cut firewood. In 84 % of the cases, an electric table saw was used. The majority of severe hand injuries were sustained with lower priced saws. Injuries occurred most frequently between 11 a. m. and 2 p. m., primarily with injuries to bones, tendons, blood vessels and nerves. Replantable amputations or partial amputations occured rarely. In 37 % of the patients, anatomical reconstruction using osteosynthesis and/or microsurgical techniques was performed successfully. Conclusions: Saw injuries to the hand are sustained almost exclusively by men. Serious injuries from low-priced table saws and due to the lack of protective covering are predominant. Preventive measures and mandatory training could reduce the number of saw injuries in the years to come. The results obtained by us largely confirm the data from previous publications. Georg Thieme Verlag KG Stuttgart · New York. Full text links |
| 104. | A novel tool for continuous fracture aftercare - Clinical feasibility and first results of a new telemetric gait analysis insoleInjury. 2016 Feb;47(2):490-4. doi: 10.1016/j.injury.2015.11.004. Epub 2015 Nov 12. AuthorsBenedikt J Braun 1 , Eva Bushuven 2 , Rebecca Hell 3 , Nils T Veith 3 , Jan Buschbaum 3 , Joerg H Holstein 3 , Tim Pohlemann 3 Affiliations
AbstractWeight bearing after lower extremity fractures still remains a highly controversial issue. Even in ankle fractures, the most common lower extremity injury no standard aftercare protocol has been established. Average non weight bearing times range from 0 to 7 weeks, with standardised, radiological healing controls at fixed time intervals. Recent literature calls for patient-adapted aftercare protocols based on individual fracture and load scenarios. We show the clinical feasibility and first results of a new, insole embedded gait analysis tool for continuous monitoring of gait, load and activity. Ten patients were monitored with a new, independent gait analysis insole for up to 3 months postoperatively. Strict 20 kg partial weight bearing was ordered for 6 weeks. Overall activity, load spectrum, ground reaction forces, clinical scoring and general health data were recorded and correlated. Statistical analysis with power analysis, t-test and Spearman correlation was performed. Only one patient completely adhered to the set weight bearing limit. Average time in minutes over the limit was 374 min. Based on the parameters load, activity, gait time over 20 kg weight bearing and maximum ground reaction force high and low performers were defined after 3 weeks. Significant difference in time to painless full weight bearing between high and low performers was shown. Correlation analysis revealed a significant correlation between weight bearing and clinical scoring as well as pain (American Orthopaedic Foot and Ankle Society (AOFAS) Score rs=0.74; Olerud-Molander Score rs=0.93; VAS pain rs=-0.95). Early, continuous gait analysis is able to define aftercare performers with significant differences in time to full painless weight bearing where clinical or radiographic controls could not. Patient compliance to standardised weight bearing limits and protocols is low. Highly individual rehabilitation patterns were seen in all patients. Aftercare protocols should be adjusted to real-time patient conditions, rather than fixed intervals and limits. With a real-time measuring device high performers could be identified and influenced towards optimal healing conditions early, while low performers are recognised and missing healing influences could be corrected according to patient condition. Keywords: Aftercare performance; Ankle fracture; Continuous fracture monitoring; Gait analysis. Copyright © 2015 Elsevier Ltd. All rights reserved. Full text links |
| 105. | Characterization of the healing process in non-stabilized and stabilized femur fractures in miceArch Orthop Trauma Surg. 2016 Feb;136(2):203-11. doi: 10.1007/s00402-015-2367-7. Epub 2015 Nov 24. AuthorsT Histing 1 , K Heerschop 2 , M Klein 2 , C Scheuer 3 , D Stenger 2 , J H Holstein 2 , T Pohlemann 2 , M D Menger 3 Affiliations
AbstractBackground: Although a variety of suitable fracture models for mice exist, in many studies bone healing was still analyzed without fracture stabilization. Because there is little information whether the healing of non-stabilized fractures differs from that of stabilized fractures, we herein studied the healing process of non-stabilized compared to stabilized femur fractures. Materials and methods: Twenty-one CD-1 mice were stabilized after midshaft fracture of the femur with an intramedullary screw allowing micromovements and endochondral healing. In another 22 mice the femur fractures were left unstabilized. Bone healing was studied by radiological, biomechanical, histomorphometric and protein expression analyses. Results: Non-stabilized femur fractures revealed a significantly lower biomechanical stiffness compared to stabilized fractures. During the early phase of fracture healing non-stabilized fractures demonstrated a significantly lower amount of osseous tissue and a higher amount of cartilage tissue. During the late phase of fracture healing both non-stabilized and stabilized fractures showed almost 100 % osseous callus tissue. However, in stabilized fractures remodeling was almost completed with lamellar bone while non-stabilized fractures still showed large callus with great amounts of woven bone, indicating a delay in bone remodeling. Of interest, western blot analyses of callus tissue demonstrated in non-stabilized fractures a significantly reduced expression of vascular endothelial growth factor and a slightly lowered expression of bone morphogenetic protein-2 and collagen-10. Conclusion: Non-stabilized femur fractures in mice show a marked delay in bone healing compared to stabilized fractures. Therefore, non-stabilized fracture models may not be used to analyze the mechanisms of normal bone healing. Keywords: Bone remodeling; Fracture; Mice; Non-stabilization; Stabilization. Full text links |
| 106. | Validation and reliability testing of a new, fully integrated gait analysis insoleJ Foot Ankle Res. 2015 Sep 22:8:54. doi: 10.1186/s13047-015-0111-8. eCollection 2015. AuthorsBenedikt Johannes Braun 1 , Nils Thomas Veith 1 , Rebecca Hell 1 , Stefan Döbele 2 , Michael Roland 3 , Mika Rollmann 1 , Jörg Holstein 1 , Tim Pohlemann 1 Affiliations
AbstractBackground: A new tool (OpenGo, Moticon GmbH) was introduced to continuously measure kinetic and temporospatial gait parameters independently through an insole over up to 4 weeks. The goal of this study was to investigate the validity and reliability of this new insole system in a group of healthy individuals. Methods: Gait data were collected from 12 healthy individuals on a treadmill at two different speeds. In total, six trials of three minutes each were performed by every participant. Validation was performed with the FDM-S System (Zebris). Complete sensor data were used for a within test reliability analysis of over 10000 steps. Intraclass correlation was calculated for different gait parameters and analysis of variance performed. Results: Intraclass correlation for the validation was >0.796 for temporospatial and kinetic gait parameters. No statistical difference was seen between the insole and force plate measurements (difference between means: 36.3 ± 27.19 N; p = 0.19 and 0.027 ± 0.028 s; p = 0.36). Intraclass correlation for the reliability was >0.994 for all parameters measured. Conclusion: The system is feasible for clinical trials that require step by step as well as grouped analysis of gait over a long period of time. Comparable validity and reliability to a stationary analysis tool has been shown. Keywords: Gait analysis; Integrated insole system; Reliability; Validation. Full text links |
| 107. | Fracture healing redefinedMed Hypotheses. 2015 Dec;85(6):940-3. doi: 10.1016/j.mehy.2015.09.006. Epub 2015 Sep 5. AuthorsB J Braun 1 , M Rollmann 2 , N Veith 2 , T Pohlemann 2 Affiliations
AbstractIt is well established that local mechanical conditions and interfragmentary movement are important factors for successful bone healing and may vary dramatically with patient fracture-load and activity. Up until now however it was technically impossible to use these key influence parameters in the aftercare treatment process of human lower extremity fractures. We propose a theory that with state of the art sensor technology these biomechanical influences can not only be monitored in vivo, but also used for individualized therapy protocols. Local measurement systems for fracture healing are available but remain research tools, due to various technical issues. To investigate the biomechanical influences on healing right away surrogate sensor tools are needed. Various gait characteristics have been proposed as surrogate measures. Currently available sensor tools could be modified with the appropriate support structure to allow such measurements continuously over the course of a fracture healing. Interdisciplinary work between clinicians, software engineers with computer and biomechanical simulations is needed. Through such a sensor system human boundary conditions for fracture healing could not only be defined for the first time, but also used for a unique, extendible aftercare system. With this tool critical healing situations would be detected much earlier and could be prevented with easy activity modifications, reducing patient and socioeconomic burden of disease. The hypothesis, necessary tools and support structures are presented. Copyright © 2015 Elsevier Ltd. All rights reserved. Full text links |
| 108. | Predictors of mortality for complex fractures of the pelvic ring in the elderly: a twelve-year review from a German level I trauma centerInjury. 2015 Oct;46(10):1996-8. doi: 10.1016/j.injury.2015.07.034. Epub 2015 Aug 3. AuthorsIshaq Ojodu 1 , Tim Pohlemann 2 , Sascha Hopp 2 , Mika F R Rollmann 2 , Joerg H Holstein 2 , Steven C Herath 3 Affiliations
AbstractStudy objective: To document mortality rate and predictors of mortality in elderly patients with complex pelvic fractures. Methods: We reviewed a total of 84 subjects whose ages were above 70 years with complex pelvic fractures, admitted to our hospital from January 2001 to December 2012. A multivariate linear regression model was used to determine the predictors of mortality in the study population. The median age of the patients was 80.4 years (range 70-94 years). 65 of 84 (77%) patients were females. There were 72 Tile Type B fractures (86%) and 12 Type C fractures (14%). The most common associated injuries were thoracic, extremity and head injuries, with incidence of 13 (15%), 11 (13%), and 9 (11%), respectively. Results: The mortality rate was 10% in our study population. The initial haemoglobin on admission (p<0.01), the presence of blood vessel injuries (p<0.01) and the number of PRBCs transfused within the first six hours after admission (p<0.01) independently predicted mortality in elderly patients with complex pelvic fractures. Conclusion: Although there is a downward trend in mortality in elderly patients with complex pelvic fractures, haemodynamic instability still has a significant impact on survival of those patients. Keywords: Elderly; Mortality; Pelvic fracture; Predictors. Copyright © 2015 Elsevier Ltd. All rights reserved. Comment in
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| 109. | Stimulation of angiogenesis by cilostazol accelerates fracture healing in miceJ Orthop Res. 2015 Dec;33(12):1880-7. doi: 10.1002/jor.22967. Epub 2015 Jul 7. AuthorsSteven C Herath 1 , Thorsten Lion 1 , Moritz Klein 1 , David Stenger 1 , Claudia Scheuer 2 , Jörg H Holstein 1 , Philipp Mörsdorf 1 , Mika F R Rollmann 1 , Tim Pohlemann 1 , Michael D Menger 2 , Tina Histing 1 Affiliations
Free article AbstractCilostazol, a selective phosphodiesterase-3 inhibitor, is known to control cyclic adenosine monophosphate (c-AMP) and to stimulate angiogenesis through upregulation of pro-angiogenic factors. There is no information, however, whether cilostazol affects fracture healing. We, therefore, studied the effect of cilostazol on callus formation and biomechanics during fracture repair. Bone healing was analyzed in a murine femur fracture stabilized with an intramedullary screw. Radiological, biomechanical, histomorphometric, histochemical, and protein biochemical analyses were performed at 2 and 5 weeks after fracture. Twenty-five mice received 30 mg/kg body weight cilostazol p.o. daily. Controls (n=24) received equivalent amounts of vehicle. In cilostazol-treated animals radiological analysis at 2 weeks showed an improved healing with an accelerated osseous bridging compared to controls. This was associated with a significantly higher amount of bony tissue and a smaller amount of cartilage tissue within the callus. Western blot analysis showed a higher expression of cysteine-rich protein 61 (CYR61), bone morphogenetic protein (BMP)-4, and receptor activator of NF-kappaB ligand (RANKL). At 5 weeks, improved fracture healing after cilostazol treatment was indicated by biomechanical analyses, demonstrating a significant higher bending stiffness compared to controls. Thus, cilostazol improves fracture healing by accelerating both bone formation and callus remodeling. Keywords: BMP-4; CYR61; RANKL; cilostazol; fracture healing. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. Full text links |
| 110. | Response of endothelial cells and pericytes to hypoxia and erythropoietin in a co-culture assay dedicated to soft tissue repairMol Cell Biochem. 2015 Sep;407(1-2):29-40. doi: 10.1007/s11010-015-2451-x. Epub 2015 May 31. AuthorsGerrit Schneider 1 , Monika Bubel, Tim Pohlemann, Martin Oberringer Affiliation
AbstractThe increasing mean life expectancy of the citizens of the western world countries leads to an increase of the age-related diseases, among them soft tissue defects exhibiting inadequate healing. In order to develop new therapeutic strategies to support disturbed soft tissue repair, there is a strong need of sophisticated in vitro assays. A new assay combining scratch wounding with co-cultures of primary human microvascular endothelial cells (HDMEC) and pericytes (HPC) focuses on basic characteristics of cell interaction against the background of soft tissue repair. The cell parameters proliferation, migration and differentiation, and the release of monocyte chemoattractant protein-1 (MCP-1) were analysed in response to hypoxia (pO2 < 5 mmHg) and to erythropoietin (EPO; 50 IU/ml), a glycoprotein hormone having shown promising effects in soft tissue repair. As basic characteristics of the assay, direct cell contact in co-culture led to a weakened proliferation of both cell types, an increase of the percentage of myofibroblast-like pericytes and to a higher release of MCP-1. Hypoxia caused a proliferation decrease of HPC in co-culture, which was slightly attenuated by EPO. Hypoxia also reduced the MCP-1 release of co-cultured cells, when EPO had been added. In addition, EPO had a rather positive effect on HPC migration under hypoxia. These in vitro results allow new insights into the interaction of pericytes with endothelial cells in the context of soft tissue repair. Full text links |
| 111. | Seltene Kombinationsverletzung des Unterarmes nach AbstütztraumaChirurg. 2016 Feb;87(2):162-4. doi: 10.1007/s00104-015-0025-9. [Article in German] AuthorsN T Veith 1 , W Knopp 2 , A Pizanis 2 , T Tschernig 3 , T Pohlemann 2 , P Mörsdorf 2 Affiliations
No abstract available Full text links |
| 112. | [Penetrating injury of two body cavities with a 20 cm long dagger-like sliver after falling into a glass door]Unfallchirurg. 2015 Nov;118(11):982-6. doi: 10.1007/s00113-014-2719-8. [Article in German] AuthorsP Mörsdorf 1 , S C Herath 2 , H V Groesdonk 3 , S Hoersch 3 , T Pohlemann 2 , M Burkhardt 4 Affiliations
AbstractIn Germany the numbers of penetrating thoracic injuries are rare compared to Anglo-American countries; however, the number of cases has increased in recent years due to an increase in violent incidents. This article reports the case of a patient who suffered such a penetrating thoracic injury after a domestic accident. Operative treatment was performed according to the well-established standard treatment algorithms. Contrary to the initial assessment of the emergency doctor, substantially more severe injuries were found. Keywords: Accidental; Domestic accident; Penetrating injuries; Thoracic injuries; Treatment algorithm. Full text links |
| 113. | Comparison of healing process in open osteotomy model and open fracture model: Delayed healing of osteotomies after intramedullary screw fixationJ Orthop Res. 2015 Jul;33(7):971-8. doi: 10.1002/jor.22861. Epub 2015 Apr 10. AuthorsMoritz Klein 1 , Andrea Stieger 1 , David Stenger 1 , Claudia Scheuer 2 , Jörg H Holstein 1 , Tim Pohlemann 1 , Michael D Menger 2 , Tina Histing 1 Affiliations
Free article AbstractMurine osteotomy and fracture models have become the standard to study molecular mechanisms of bone healing. Because there is little information whether the healing of osteotomies differs from that of fractures, we herein studied in mice the healing of femur osteotomies compared to femur fractures. Twenty CD-1 mice underwent a standardized open femur osteotomy. Another 20 mice received a standardized open femur fracture. Stabilization was performed by an intramedullary screw. Bone healing was studied by micro-CT, biomechanical, histomorphometric and protein expression analyses. Osteotomies revealed a significantly lower biomechanical stiffness compared to fractures. Micro-CT showed a reduced bone/tissue volume within the callus of the osteotomies. Histomorphometric analyses demonstrated also a significantly lower amount of osseous tissue in the callus of osteotomies (26% and 88% after 2 and 5 weeks) compared to fractures (50% and 100%). This was associated with a delayed remodeling. Western blot analyses demonstrated comparable BMP-2 and BMP-4 expression, but higher levels of collagen-2, CYR61 and VEGF after osteotomy. Therefore, we conclude that open femur osteotomies in mice show a markedly delayed healing when stabilized less rigidly with an intramedullary screw. This should be considered when choosing a model for studying the mechanisms of bone healing in mice. Keywords: CYR61; VEGF; bone healing; callus remodeling; mouse. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. Full text links |
| 114. | Posterior symphyseal spurs--an unusual differential diagnosis in athletes with groin painPhys Sportsmed. 2015 May;43(2):150-4. doi: 10.1080/00913847.2015.1012038. Epub 2015 Feb 11. AuthorsSascha Jörg Hopp 1 , Ishaq Ojodu, Tim Pohlemann, Jens Kelm Affiliation
AbstractWe set out to highlight the significance of posterior symphyseal spurs as an unusual diagnostic possibility in athletes with chronic groin pain and to demonstrate that operative resection was successful in quickly and safely returning the patients to sporting activities. Five competitive nonprofessional male athletes, three soccer players, and two marathon runners (median age: 30 [26/33] years), who presented to us with significant groin and central pubic pain with duration of at least 12 months, and who had failed conservative or surgical interventions (symphyseal plating), were evaluated. Physical examination as well as pelvic radiographs confirmed the diagnosis of posterior symphyseal spurs. Four out of five athletes underwent complete resection of the spur. Size of spurs was 2.2 (1.3/2.9) cm (median) with four of them posterosuperiorly and one posterocentrally located. All of them had uneventful postoperative recovery period and were still pain-free at the latest follow up after 26.6 months (24/30). Median time-to-return to competitive sports level was 10 weeks (8/13). None of the patients developed pubic instability due to symphyseal spur resection. The results of considerable postoperative improvement in our patients highlight the significance of posterior symphyseal spurs as a diagnostic possibility in athletes with chronic groin pain. Keywords: Symphyseal spurs; athletes; groin pain; pubalgia; pubic symphysis; surgery. Full text links |
| 115. | Dynamic locking screw improves fixation strength in osteoporotic bone: an in vitro study on an artificial bone modelInt Orthop. 2015 Apr;39(4):761-8. doi: 10.1007/s00264-014-2658-6. Epub 2015 Jan 28. AuthorsTim Pohlemann 1 , Boyko Gueorguiev, Yash Agarwal, Dieter Wahl, Christoph Sprecher, Karsten Schwieger, Mark Lenz Affiliation
AbstractPurpose: The novel dynamic locking screw (DLS) was developed to improve bone healing with locked-plate osteosynthesis by equalising construct stiffness at both cortices. Due to a theoretical damping effect, this modulated stiffness could be beneficial for fracture fixation in osteoporotic bone. Therefore, the mechanical behaviour of the DLS at the screw-bone interface was investigated in an artificial osteoporotic bone model and compared with conventional locking screws (LHS). Methods: Osteoporotic surrogate bones were plated with either a DLS or a LHS construct consisting of two screws and cyclically axially loaded (8,500 cycles, amplitude 420 N, increase 2 mN/cycle). Construct stiffness, relative movement, axial screw migration, proximal (P) and distal (D) screw pullout force and loosening at the bone interface were determined and statistically evaluated. Results: DLS constructs exhibited a higher screw pullout force of P 85 N [standard deviation (SD) 21] and D 93 N (SD 12) compared with LHS (P 62 N, SD 28, p = 0.1; D 57 N, SD 25, p < 0.01) and a significantly lower axial migration over cycles compared with LHS (p = 0.01). DLS constructs showed significantly lower axial construct stiffness (403 N/mm, SD 21, p < 0.01) and a significantly higher relative movement (1.1 mm, SD 0.05, p < 0.01) compared with LHS (529 N/mm, SD 27; 0.8 mm, SD 0.04). Conclusion: Based on the model data, the DLS principle might also improve in vivo plate fixation in osteoporotic bone, providing enhanced residual holding strength and reducing screw cutout. The influence of pin-sleeve abutment still needs to be investigated. Full text links |
| 116. | [Purpura fulminans of the adult--a hematological emergency]Dtsch Med Wochenschr. 2014 Dec;139(50):2597-601. doi: 10.1055/s-0034-1387428. Epub 2014 Dec 3. [Article in German] AuthorsN T Veith 1 , T Tschernig 2 , B J Braun 1 , T Pohlemann 1 , G Aßmann 3 Affiliations
AbstractHistory and clinical findings: A 51-year-old female patient with history of longterm drug abuse, was admitted to our hospital with large, stocking-shaped areas of painful, non-displaceable confluent bruising reaching up to the groin. Investigations: The emergency laboratory tests showed leucopenia, thrombocytopenia and anemia as well as a distinct protein C deficiency. Diagnosis, treatment and course: Purpura fulminans was diagnosed and treated with an initial dose of protein C. The patient survived and the skin necrosis can be treated. Conclusion: Purpura fulminans is an internistic and dermatological emergency situation which can lead to shock through consumptive coagulopathy. The serious course of disease can be prevented by rapid treatment with protein C. © Georg Thieme Verlag KG Stuttgart · New York. Full text links |
| 117. | Evaluation of the effectiveness of the angular stable locking system in patients with distal tibial fractures treated with intramedullary nailing: a multicenter randomized controlled trialJ Bone Joint Surg Am. 2014 Nov 19;96(22):1889-97. doi: 10.2106/JBJS.M.01355. AuthorsDankward Höntzsch 1 , Klaus-Dieter Schaser 2 , Gunther O Hofmann 3 , Tim Pohlemann 4 , Einar Sturla Hem 5 , Erik Rothenbach 6 , Christian Krettek 7 , René Attal 8 Affiliations
AbstractBackground: Angular stable locking of intramedullary nails has been shown to enhance fixation stability of tibial fractures in biomechanical and animal studies. The aim of our study was to assess whether use of the angular stable locking system or conventional locking resulted in earlier full weight-bearing with minimum pain for patients with a distal tibial fracture treated with an intramedullary nail. Methods: A prospective multicenter, randomized, patient-blinded trial was conducted with adults who had a distal tibial fracture. Patients' fractures were managed with an intramedullary nail locked with either an angular stable locking system or conventional locking screws. Outcomes were evaluated at six weeks, twelve weeks, six months, and one year after surgery. Time to full weight-bearing with minimum pain was calculated with use of daily entries from patient diaries. Secondary outcomes included pain at the fracture site under load, quality of life, gait analysis, mobility, radiographic findings, and adverse events. Results: One hundred and forty-two patients were randomly allocated to two treatment groups: seventy-five to the group receiving intramedullary nailing with the angular stable locking system and sixty-seven to the group receiving conventional intramedullary nailing. No clinically important differences were found for either the primary or secondary outcome parameters between the groups during the entire follow-up period. Conclusions: Use of an angular stable locking system with intramedullary nailing did not improve the outcome compared with conventional locking screws in the treatment of distal tibial fractures. Trial registration: ClinicalTrials.gov NCT00875992. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated. Full text links |
| 118. | Pelvic fracture in multiple trauma: are we still up-to-date with massive fluid resuscitation?Injury. 2014 Oct:45 Suppl 3:S70-5. doi: 10.1016/j.injury.2014.08.021. AuthorsMarkus Burkhardt 1 , Alexander Kristen 2 , Ulf Culemann 3 , Daniel Koehler 4 , Tina Histing 5 , Joerg H Holstein 6 , Antonius Pizanis 7 , Tim Pohlemann 8 ; TraumaRegister DGU; German Pelvic Injury Register Affiliations
AbstractUntil today the mortality of complex pelvic trauma remains unacceptably high. On the one hand this could be attributed to a biological limit of the survivable trauma load, on the other hand side an ongoing inadequate treatment might be conceivable too. For the management of multiple trauma patients with life-threatening pelvic fractures, there is ongoing international debate on the adequate therapeutic strategy, e.g. arterial embolization or pelvic packing, as well as aggressive or restrained volume therapy. Whereas traditional pelvis-specific trauma algorithms still recommend massive fluid resuscitation, there is upcoming evidence that a restrained volume therapy in the preclinical setting may improve trauma outcomes. Less intravenous fluid administration may also reduce haemodilution and concomitant trauma-associated coagulopathy. After linking the data of the TraumaRegister DGU(®) and the German Pelvic Injury Register, for the first time, the initial fluid management for complex pelvic traumas as well as for different Tile/OTA types of pelvic ring fractures could be addressed. Unfortunately, the results could not answer the question of the adequate fluid resuscitation but confirmed the actuality of massive fluid resuscitation in the prehospital and emergency room setting. Low-volume resuscitation seems not yet accepted in practice in managing multiple trauma patients with pelvic fractures at least in Germany. Nevertheless, prevention of exsanguination and of complications like multiple organ dysfunction syndrome still poses a major challenge in the management of complex pelvic ring injuries. Even nowadays, fluid management for trauma, not only for pelvic fractures, remains a controversial area and further research is mandatory. Keywords: Coagulopathy; Fluid resuscitation; Haemorrhage; Management; Mortality; Pelvic fractures. Copyright © 2014 Elsevier Ltd. All rights reserved. Full text links |
| 119. | [Fractures of the acetabulum: complications and joint replacement]Z Orthop Unfall. 2014 Aug;152(4):399-413. doi: 10.1055/s-0034-1382862. Epub 2014 Aug 21. [Article in German] AuthorsS C Herath 1 , J H Holstein 1 , A Pizanis 1 , T Pohlemann 1 Affiliation
AbstractAcetabular fractures assume a special role amongst the fractures of the pelvis, because they involve a major weight-bearing joint. As those fractures mostly result from exposure to great force, and because of their location in an anatomically complex region, a high rate of complications has to be anticipated. Besides general and perioperative complications long-term consequences, especially post-traumatic arthrosis, are relevant problems when it comes to treating fractures of the acetabulum. The primary reconstruction of the acetabulum, as well as a possibly necessary prosthetic replacement of the hip joint, makes high demands on the diagnostic and operative capabilities of the attending physician. Exact knowledge of the specific risks and pitfalls for each type of fracture and for the specific surgical techniques is crucial for a successful treatment. Due to the much worse long-term outcome when compared to primary total hip replacement in patients with osteoarthritis, acetabular fractures should, regardless of the patient's age, whenever possible be treated by operative reconstruction. Georg Thieme Verlag KG Stuttgart · New York. Full text links |
| 120. | Proper coding of the Abbreviated Injury Scale: can clinical parameters help as surrogates in estimating blood loss?Eur J Trauma Emerg Surg. 2014 Aug;40(4):473-9. doi: 10.1007/s00068-013-0335-x. Epub 2013 Oct 5. AuthorsM Burkhardt 1 , J H Holstein 2 , P Moersdorf 3 , A Kristen 4 , R Lefering 5 , T Pohlemann 6 , A Pizanis 7 ; TraumaRegister DGU Affiliations
AbstractPurpose: The Abbreviated Injury Scale (AIS) requires the estimation of the lost blood volume for some severity assignments. This study aimed to develop a rule of thumb for facilitating AIS coding by using objective clinical parameters as surrogate markers of blood loss. Methods: Using the example of pelvic ring fractures, a retrospective analysis of TraumaRegister DGU(®) data from 2002 to 2011 was performed. As potential surrogate markers of blood loss, we recorded the hemoglobin (Hb) level, systolic blood pressure (SBP), base excess (BE), Quick's value, units of packed red blood cells (PRBCs) transfused before intensive care unit (ICU) admission, and mortality within 24 h. Results: We identified 11,574 patients with pelvic ring fractures (Tile/OTA classification: 39 % type A, 40 % type B, 21 % type C). Type C fractures were 73.1 % AISpelvis 4 and 26.9 % AISpelvis 5. Type B fractures were 47 % AISpelvis 3, 47 % AISpelvis 4, and 6 % AISpelvis 5. In type C fractures, cut-off values of <7 g/dL Hb, <90 mmHg SBP, <-9 mmol/L BE, <35 % Quick's value, >15 units PRBCs, and death within 24 h had a positive predictive value of 47 % and a sensitivity of 62 % for AISpelvis 5. In type B fractures, these cut-off values had poor sensitivity (48 %) and positive predictive value (11 %) for AISpelvis 5. Conclusions: We failed to develop a rule of thumb for facilitating a proper future AIS coding using the example of pelvic ring fractures. The estimation of blood loss for severity assignment still remains a noteworthy weakness in the AIS coding of traumatic injuries. Keywords: Abbreviated Injury Scale (AIS); Coding; Estimated blood loss; Pelvic ring fracture; Rule of thumb. Full text links |
| 121. | Arthroscopic pubic symphysis debridement and adductor enthesis repair in athletes with athletic pubalgia: technical note and video illustrationArch Orthop Trauma Surg. 2014 Nov;134(11):1595-9. doi: 10.1007/s00402-014-2065-x. Epub 2014 Jul 24. AuthorsSascha Hopp 1 , Masjudin Tumin, Peter Wilhelm, Tim Pohlemann, Jens Kelm Affiliation
AbstractWe elaborately describe our novel arthroscopic technique of the symphysis pubis in athletes with osteitis pubis and concomitant adductor enthesopathy who fail to conservative treatment modalities. The symphysis pubis is debrided arthroscopically and the degenerated origin of adductor tendon (enthesis) is excised and reattached. With our surgical procedure the stability of the symphysis pubis is successfully preserved and the adductor longus enthesopathy simultaneously addressed in the same setting. Full text links |
| 122. | Analysis of cellular composition of co-culture spheroidsAnn Anat. 2014 Sep;196(5):303-11. doi: 10.1016/j.aanat.2014.05.038. Epub 2014 Jun 10. AuthorsNatalie Dorst 1 , Martin Oberringer 2 , Ute Grässer 3 , Tim Pohlemann 4 , Wolfgang Metzger 5 Affiliations
Abstract3D spheroids and in particular co-culture spheroids reflect the natural organization of cells in tissues much better than 2D cell cultures as indicated by differences in cellular phyisology. However, most methods to analyze cells were established for 2D cultures and cannot easily be applied to spheroids. This study has aimed to demonstrate the possibility of quantification of the cellular composition of co-culture spheroids without previous dissociation into single cells. Prior to the generation of the spheroids, human endothelial cells, osteoblasts and fibroblasts were stained with fluoresent dyes for living cells. Co-culture spheroids of defined stoichiometric compositions were generated by the liquid overlay technique, cultivated for one, three or six days, respectively, and afterwards snap-frozen in liquid nitrogen. Cryo-sections of co-culture spheroids were analyzed by fluorescence microscopy and a newly established semi-automatic measuring routine. In order to compare the results, spheroids of one group were dissociated and the cellular composition was quantified by FACS-analysis. Staining efficiencies were higher than 95% as quantified in preliminary experiments with 2D cultures. Depending on the staining procedure, variations from uniform to punctate signals were detected. The size of all co-culture spheroids decreased over time and snap-freezing did not lead to shrinkage of the spheroids. We were able to detect organizational patterns of different cell types within the spheroids. It was possible to determine the cellular composition by quantitative microscopic analyses of cryo-sections as it could be confirmed by flow cytometric analyses. Depending on the experimental requirements, a combination of both methods might lead to valuable synergy. Keywords: Cellular composition; Co-culture spheroids; Dissociation; Endothelial cells; Fibroblasts; Fluorescence staining; Osteoblasts. Copyright © 2014 Elsevier GmbH. All rights reserved. Full text links |
| 123. | Arthroscopic debridement of the pubic symphysis: an experimental studyKnee Surg Sports Traumatol Arthrosc. 2015 Sep;23(9):2568-75. doi: 10.1007/s00167-014-3105-3. Epub 2014 Jun 11. AuthorsSascha Hopp 1 , Ulf Culemann, Ishaq Ojodu, Tim Pohlemann, Jens Kelm Affiliation
AbstractPurpose: Open curettage of the symphysis has shown promising results in patients with recalcitrant osteitis pubis. However, this has been bedevilled with an extended intraoperative morbidity. Aim of this study was to come up with a novel arthroscopic debridement of the pubic symphysis and to bring to the fore the potential risks of soft tissue damage. Methods: This study was conducted on six human cadavers (mean age 83 years). CT scans were obtained for measurement of the symphyseal morphology. Consequent upon these measurements, four different potential arthroscopic portals were defined with the intention to gain adequate insight and to reach the whole joint space with instruments: one suprapubic portal and three anterior portals (antero-superior, antero-central and antero-inferior). Soft tissue, except for musculotendinous attachments and neurovascular structures, was dissected. A two-portal arthroscopic debridement under image intensifier control with resection of the symphyseal disc and abrasion of the subchondral bone were performed. Results: Considering the narrow joint space, small instruments/scope (4.5/2.7 mm) is recommended. Correct portal placement and debridement procedure can only be reliably performed under fluoroscopic imaging in two radiographic projections (outlet and inlet view) with a mean total fluoroscopic time of 15-20 s and a dose area product between 100 and 120 cGy cm(2). Two portals have proved beneficial: the suprapubic portal for instruments and the antero-central portal for the scope. Other portals had several limitations, e.g. potential instrumental conflict (anterior-superior) or damaging of neurovascular and other soft tissue structures (anterior-inferior). Conclusion: With well-defined arthroscopic portals and adherence to basic principles of arthroscopic surgery, debridement of the pubic symphysis can be performed reproducibly without compromising important anatomical structures. This less invasive arthroscopic debridement is a safely applicable procedure and therefore might be a reasonable alternative to open curettage. One may assume that this technique will lead to a shorter rehabilitation time and will provide a successful therapy especially in the treatment of professional athletes in the future. |
| 124. | [Funktionsoberarzt. Pseudo-title or meaningful position?]Unfallchirurg. 2014 Jun;117(6):557-9. doi: 10.1007/s00113-014-2581-8. [Article in German] AuthorsT Histing 1 , M Burkhardt, M Rollmann, M D Menger, T Pohlemann Affiliation
AbstractThe position of the Funktionsoberarzt ("functioning senior physician") is to date not specified. Nevertheless, in the majority of hospitals the position exists, although the function and responsibilities are not clearly defined. Frequently, it is thought that the position represents a consultant who works independently, but who is still supported by experienced colleagues to achieve the full qualification for a senior physician. In contrast, others indicate that the position represents a consultant who works as a senior physician with all responsibilities, but without an established post and without the corresponding reimbursement. A critical disadvantage of the position is that frequently the duties of both a resident and senior physician must be managed. Rotation between the two functions results in a higher workload, and the lack of identity and acceptance may lead to frustration. Therefore, we feel that the position is only meaningful if the Funktionsoberarzt works exclusively as a senior physician who is supported for complex surgeries and decisions by more experienced colleagues. In addition, the position should only be temporary and the time period for the position should be defined in advance. Full text links |
| 125. | Computer-assisted fracture reduction: a new approach for repositioning femoral fractures and planning reduction pathsInt J Comput Assist Radiol Surg. 2015 Feb;10(2):149-59. doi: 10.1007/s11548-014-1011-2. Epub 2014 May 10. AuthorsJan Buschbaum 1 , Rainer Fremd, Tim Pohlemann, Alexander Kristen Affiliation
AbstractPurpose: Reduction is a crucial step in the surgical treatment of bone fractures to achieve anatomical alignment and facilitate healing. Surgical planning for treatment of simple femoral fractures requires suitable gentle reduction paths. A plan with optimal movement of fracture fragments from the initial to the desired target position should improve the reduction procedure. A virtual environment which repositions the fracture fragments automatically and provides the ability to plan reduction paths was developed and tested. Methods: Virtual 3D osseous fragments are created from CT scans. Based on the computed surface curvatures, strongly curved edges are selected and fracture lines are generated. After assignment of matching points, the lines are compared and the desired target position is calculated. Planning of reduction paths was achieved using a reference-coordinate-system for the computation of reduction parameters. The fracture is reduced by changing the reduction parameters step by step until the target position is reached. To test this system, nine different fractured SYNBONE models and one human fracture were reduced, based on CT scans with varying resolution. Results: The highest mean translational error is 1.2 ± 0.9 (mm), and the rotational error is 2.6 ± 2.8 (°), both of which are considered as clinically acceptable. The reduction paths can be planned manually or semi-automatically for each fracture. Conclusions: Automated fracture reduction was achieved using a system based on preoperative CT scans. The automated system provides a clinically feasible basis for planning optimal reduction paths that may be augmented by further computer- or robot-assisted applications. Full text links |
| 126. | Induction of osteogenic differentiation by nanostructured alumina surfacesJ Biomed Nanotechnol. 2014 May;10(5):831-45. doi: 10.1166/jbn.2014.1775. AuthorsWolfgang Metzger, Benedikt Schwab, Marina M Miro, Sibylle Grad, Angharad Simpson, Michael Veith, Gunther Wennemuth, Vladimir Zaporojtchenko, Sophie Verrier, Jessica S Hayes, Monika Bubel, Tim Pohlemann, Martin Oberringer, Cenk Aktas
AbstractPermanent orthopedic implants are becoming increasingly important due to the demographic development. Their optimal osseointegration is key in obtaining good secondary stability. For anchorage dependent cells, topographic features of a surface play an essential role for cell adhesion, proliferation, differentiation and biomineralization. We studied the topographical effect of nanostructured alumina surfaces prepared by chemical vapor deposition on osteogenic differentiation and growth of human osteoblasts. Chemical vapor deposition of the single source precursor (tBuOAIH2)2 led to synthesis of one dimensional alumina nanostructures of high purity with a controlled stoichiometry. We fabricated different topographic features by altering the distribution density of deposited one dimensional nanostructures. Although the topography differed, all surfaces exhibited identical surface chemistry, which is the key requirement for systematically studying the effect of the topography on cells. Forty-eight hours after seeding, cell density and cell area were not affected by the nanotopography, whereas metabolic activity was reduced and formation of actin-fibres and focal adhesions was impaired compared to the uncoated control. Induction of osteogenic differentiation was demonstrated via up-regulation of alkaline phosphatase, bone sialoprotein, osteopontin and Runx2 at the mRNA level, demonstrating the potential of nanostructured surfaces to improve the osseointegration of permanent implants. |
| 127. | [Complex pelvic traumas : data linkage of the German Pelvic Injury Register and the TraumaRegister DGU®]Unfallchirurg. 2015 Nov;118(11):957-62. doi: 10.1007/s00113-014-2565-8. [Article in German] AuthorsM Burkhardt 1 , U Nienaber 2 , J Krause 3 , A Pizanis 3 , P Moersdorf 3 , U Culemann 4 , E Aghayev 5 , T Paffrath 6 , T Pohlemann 3 , J H Holstein 3 ; Beckenregister DGU; TraumaRegister DGU® Affiliations
Free article AbstractBackground: Complex pelvic traumas, i.e., pelvic fractures accompanied by pelvic soft tissue injuries, still have an unacceptably high mortality rate of about 18 %. Patients and methods: We retrospectively evaluated an intersection set of data from the TraumaRegister DGU® and the German Pelvic Injury Register from 2004-2009. Patients with complex and noncomplex pelvic traumas were compared regarding their vital parameters, emergency management, stay in the ICU, and outcome. Results: From a total of 344 patients with pelvic injuries, 21 % of patients had a complex and 79 % a noncomplex trauma. Complex traumas were significantly less likely to survive (16.7 % vs. 5.9 %). Whereas vital parameters and emergency treatment in the preclinical setting did not differ substantially, patients with complex traumas were more often in shock and showed acute traumatic coagulopathy on hospital arrival, which resulted in more fluid volumes and transfusions when compared to patients with noncomplex traumas. Furthermore, patients with complex traumas had more complications and longer ICU stays. Conclusion: Prevention of exsanguination and complications like multiple organ dysfunction syndrome still pose a major challenge in the management of complex pelvic traumas. Keywords: Emergency management; Mortality; Pelvic fracture; Pelvic trauma, complex; Registry. Full text links |
| 128. | [Current treatment of pelvic ring fractures]Unfallchirurg. 2014 Feb;117(2):145-59; quiz 160-1. doi: 10.1007/s00113-014-2558-7. [Article in German] AuthorsU Culemann 1 , H J Oestern, T Pohlemann Affiliation
AbstractPelvic injuries are often associated with multiple injuries of other body regions, neurovascular and visceral lesions, as well as hemodynamic instability. The use of a standardized classification characterizing the severity and stability of pelvic fractures and the early stabilization of pelvic ring injuries in appreciation of damage control principles has helped to improve the number of survivors. This is particularly necessary due to the higher number of older patients. Complex pelvic trauma still represents a life-threatening situation for the patient, particularly in multiple traumatized patients. Standardized clinical investigations and modern concepts even in the preclinical therapy of complex pelvic fractures make a contribution to enhancement of treatment options. Because of the still problematic long-term results after surgery of instable pelvic fractures, the need for modern treatment concepts has to be adapted to the requirements. Full text links |
| 129. | [Quality of life after multiple trauma]Chirurg. 2014 Mar;85(3):208, 210-4. doi: 10.1007/s00104-013-2601-1. [Article in German] AuthorsP Mörsdorf 1 , S C Becker, J H Holstein, M Burkhardt, T Pohlemann Affiliation
AbstractBackground: Multiple trauma is an independent injury pattern which, because of its complexity, is responsible for 25 % of the costs for the treatment of all injured patients. Because of the often long-lasting physical impairment and the high incidence of residual permanent handicaps, it is apparent that multiple trauma can lead to a reduction in patient quality of life. Objectives: The aim of this study was to give an overview of the known data concerning the change in quality of life for multiple trauma patients. Furthermore, predictors for the reduction of quality of life after multiple trauma will be identified. Materials and methods: A MedLine search was performed to identify studies dealing with the outcome after multiple trauma. Results: In addition to functional outcome parameters, the term quality of life has become more important in recent years when it comes to evaluating the outcome following injury. While the mortality after multiple trauma could be significantly reduced over the years, there is no comparable effect on the quality of life. Predictors for a worse quality of life after multiple trauma are female gender, high age, low social status, concomitant head injuries and injury to the lower extremities. Conclusion: The fact that mortality after multiple trauma has decreased but not impairment of the quality of life makes it clear that in addition to the acute medical treatment, a follow-up treatment including not only physiotherapy but also psychotherapy is crucial for multiple trauma patients. Full text links |
| 130. | [Primary cancellous bone formation around micro-chambered beads]Rev Esp Cir Ortop Traumatol. 2014 May-Jun;58(3):131-7. doi: 10.1016/j.recot.2013.11.003. Epub 2014 Feb 8. [Article in Spanish] AuthorsM E Draenert 1 , Y Draenert 2 , K Draenert 2 , T Pohlemann 3 , M Erler 4 Affiliations
AbstractObjectives: The question has been raised whether benign bone defects in patients can be treated with bone forming osteoconductive ceramics achieving primarily a cancellous bone scaffold, which is under load from the beginning. Material and methods: Ten reconstructions were performed in 9patients (6women and 3male), with a mean age of 49 (25-65)years, suffering a high variety of epi- and metaphyseal defects, four tibial fractures, two calcaneal fractures, one pathological phalangeal fracture, one chondroma of the distal femur and two open-wedge osteotomies were filled with micro-chambered ceramic beads of 4 and 6mm in diameter. The mean follow up was 22 (7- 8)months. X-rays and CT-scans formed the basis for the evaluation of the reconstruction of the cancellous bone scaffolds. Results: All cancellous structures were rebuilt, if completely filled with bone-forming elements. If the filling was incomplete, no physiological cancellous bone scaffold resulted. The β-TCP micro-chambered beads were completely reabsorbed or sandwich-like incorporated at the time of evaluation. The HA micro-chambered beads revealed a contrast enhancement and were integrated in the osseous construction of the bone scaffold. Conclusion: Primary cancellous bone formation can be achieved with osteoconductive ceramic micro-chambered beads and can be combined with any osteosynthesis for stable fixation. Keywords: Bone defect; Bone substitute; Cancellous bone; Defecto óseo; Fractura; Fracture; Hueso esponjoso; Open wedge osteotomy; Osteotomía de apertura; Sustitutivo óseo. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved. Full text links |
| 131. | Generation of co-culture spheroids as vascularisation units for bone tissue engineeringEur Cell Mater. 2013 Nov 6:26:222-33. doi: 10.22203/ecm.v026a16. AuthorsR Walser 1 , W Metzger, A Görg, T Pohlemann, M D Menger, M W Laschke Affiliation
Free article AbstractCell spheroids represent attractive building units for bone tissue engineering, because they provide a three-dimensional environment with intensive direct cell-cell contacts. Moreover, they allow for co-culture of both osteoblasts and vessel-forming cells, which may markedly increase their survival and vascularisation after transplantation. To test this hypothesis, we generated co-culture spheroids by aggregating different combinations of primary human osteoblasts (HOB), human dermal microvascular endothelial cells (HDMEC) and normal human dermal fibroblasts (NHDF) using the liquid overlay technique. Mono-culture spheroids consisting either of HOB or HDMEC served as controls. After in vitro characterisation, the different spheroids were transplanted into dorsal skinfold chambers of CD1 nu/nu mice to study in vivo their viability and vascularisation over a 2-week observation period by means of repetitive intravital fluorescence microscopy and immunohistochemistry. In vitro, co-culture spheroids containing HDMEC rapidly formed dense tubular vessel-like networks within 72 h and exhibited a significantly decreased rate of apoptotic cell death when compared to mono-culture HDMEC spheroids. After transplantation, these networks interconnected to the host microvasculature by external inosculation. Of interest, this process was most pronounced in HOB-HDMEC spheroids and could not further be improved by the addition of NHDF. Accordingly, HOB-HDMEC spheroids were larger when compared to the other spheroid types. These findings indicate that HOB-HDMEC spheroids exhibit excellent properties to preserve viability and to promote proliferation and vascularisation. Therefore, they may be used as functional vascularisation units in bone tissue engineering for the seeding of scaffolds or for the vitalisation of non-healing large bone defects. Full text links |
| 132. | Intra- and postoperative complications of navigated and conventional techniques in percutaneous iliosacral screw fixation after pelvic fractures: Results from the German Pelvic Trauma RegistryInjury. 2013 Dec;44(12):1765-72. doi: 10.1016/j.injury.2013.08.008. Epub 2013 Aug 15. AuthorsJörn Zwingmann 1 , Norbert P Südkamp, Benjamin König, Ulf Culemann, Tim Pohlemann, Emin Aghayev, Hagen Schmal Affiliation
AbstractBackground: Percutaneous iliosacral screw placement following pelvic trauma is a very demanding technique involving a high rate of screw malpositions possibly associated with the risk of neurological damage or inadequate stability. In the conventional technique, the screw's correct entry point and the small target corridor for the iliosacral screw may be difficult to visualise using an image intensifier. 2D and 3D navigation techniques may therefore be helpful tools. The aim of this multicentre study was to evaluate the intra- and postoperative complications after percutaneous screw implantation by classifying the fractures using data from a prospective pelvic trauma registry. The a priori hypothesis was that the navigation techniques have lower rates of intraoperative and postoperative complications. Methods: This study is based on data from the prospective pelvic trauma registry introduced by the German Society of Traumatology and the German Section of the AO/ASIF International in 1991. The registry provides data on all patients with pelvic fractures treated between July 2008 and June 2011 at any one of the 23 Level I trauma centres contributing to the registry. Results: A total of 2615 patients were identified. Out of these a further analysis was performed in 597 patients suffering injuries of the SI joint (187×with surgical interventions) and 597 patients with sacral fractures (334×with surgical interventions). The rate of intraoperative complications was not significantly different, with 10/114 patients undergoing navigated techniques (8.8%) and 14/239 patients in the conventional group (5.9%) for percutaneous screw implantation (p=0.4242). Postoperative complications were analysed in 30/114 patients in the navigated group (26.3%) and in 70/239 patients (29.3%) in the conventional group (p=0.6542). Patients who underwent no surgery had with 66/197 cases (33.5%) a relatively high rate of complications during their hospital stay. The rate of surgically-treated fractures was higher in the group with more unstable Type-C fractures, but the fracture classification had no significant influence on the rate of complications. Discussion: In this prospective multicentre study, the 2D/3D navigation techniques revealed similar results for the rate of intraoperative and postoperative complications compared to the conventional technique. The rate of neurological complications was significantly higher in the navigated group. Keywords: German Pelvic Trauma Registry; Iliosacral screw; Navigation; Pelvic fracture; SI screw. Copyright © 2013 Elsevier Ltd. All rights reserved. Full text links |
| 133. | [Current treatment of pelvic ring fractures]Chirurg. 2013 Sep;84(9):809-26. doi: 10.1007/s00104-012-2391-x. [Article in German] AuthorsU Culemann 1 , H J Oestern, T Pohlemann Affiliation
AbstractPelvic injuries are often associated with multiple injuries of other body regions, neurovascular and visceral lesions, as well as hemodynamic instability. The use of a standardized classification characterizing the severity and stability of pelvic fractures and the early stabilization of pelvic ring injuries in appreciation of damage control principles has helped to improve the number of survivors. This is particularly necessary due to the higher number of older patients.Complex pelvic trauma still represents a life-threatening situation for the patient, particularly in multiple traumatized patients. Standardized clinical investigations and modern concepts even in the preclinical therapy of complex pelvic fractures make a contribution to enhancement of treatment options. Because of the still problematic long-term results after surgery of instable pelvic fractures, the need for modern treatment concepts has to be adapted to the requirements. Full text links |
| 134. | The posterior two-portal approach for reconstruction of scapula fractures: results of 39 patientsInjury. 2013 Nov;44(11):1630-5. doi: 10.1016/j.injury.2013.07.020. Epub 2013 Aug 6. AuthorsA Pizanis 1 , G Tosounidis, C Braun, T Pohlemann, R J Wirbel Affiliation
AbstractThe purpose of this study was to describe the so-called posterior two-portal approach to the scapula in detail and to investigate the clinical outcome of patients with displaced glenoid and scapular neck fractures who were surgically treated using this approach. From February 1992 to August 2008, 39 patients (30 men and nine women; mean age: 53 years) with scapular fractures underwent surgical fixation at our institution. Thirty-three patients had glenoid fractures and six had unstable scapular neck fractures. All patients were treated via the two-portal approach. The reduction was evaluated radiographically, and the clinical results were analysed using the Constant score. The mean follow-up period was 78 months (range: 6-168). In 24 of the 33 glenoid fractures, the reduction was anatomical. The mean Constant score was 82.3 (range: 35-100) points. In one case, an early postoperative wound infection was cured by local revision, and one patient developed posttraumatic osteoarthritis of the acromioclavicular joint after 2 years. Only one patient developed specific glenohumeral degeneration after non-anatomical reduction. The posterior two-portal approach allows for a good visualisation of the posterior scapular neck and the glenoid area, facilitating the reduction and safe internal fixation of dislocated scapular neck and glenoid fractures. Keywords: Scapula fracture; Scapula surgery; Surgical approach. Copyright © 2013 Elsevier Ltd. All rights reserved. Full text links |
| 135. | Compression and contact area of anterior strut grafts in spinal instrumentation: a biomechanical studyBMC Musculoskelet Disord. 2013 Aug 26:14:254. doi: 10.1186/1471-2474-14-254. AuthorsAntonius Pizanis 1 , Jörg H Holstein, Felix Vossen, Markus Burkhardt, Tim Pohlemann Affiliation
AbstractBackground: Anterior bone grafts are used as struts to reconstruct the anterior column of the spine in kyphosis or following injury. An incomplete fusion can lead to later correction losses and compromise further healing. Despite the different stabilizing techniques that have evolved, from posterior or anterior fixating implants to combined anterior/posterior instrumentation, graft pseudarthrosis rates remain an important concern. Furthermore, the need for additional anterior implant fixation is still controversial. In this bench-top study, we focused on the graft-bone interface under various conditions, using two simulated spinal injury models and common surgical fixation techniques to investigate the effect of implant-mediated compression and contact on the anterior graft. Methods: Calf spines were stabilised with posterior internal fixators. The wooden blocks as substitutes for strut grafts were impacted using a "pressfit" technique and pressure-sensitive films placed at the interface between the vertebral bone and the graft to record the compression force and the contact area with various stabilization techniques. Compression was achieved either with posterior internal fixator alone or with an additional anterior implant. The importance of concomitant ligament damage was also considered using two simulated injury models: pure compression Magerl/AO fracture type A or rotation/translation fracture type C models. Results: In type A injury models, 1 mm-oversized grafts for impaction grafting provided good compression and fair contact areas that were both markedly increased by the use of additional compressing anterior rods or by shortening the posterior fixator construct. Anterior instrumentation by itself had similar effects. For type C injuries, dramatic differences were observed between the techniques, as there was a net decrease in compression and an inadequate contact on the graft occurred in this model. Under these circumstances, both compression and the contact area on graft could only be maintained at high levels with the use of additional anterior rods. Conclusions: Under experimental conditions, we observed that ligamentous injury following type C fracture has a negative influence on the compression and contact area of anterior interbody bone grafts when only an internal fixator is used for stabilization. Because of the loss of tension banding effects in type C injuries, an additional anterior compressing implant can be beneficial to restore both compression to and contact on the strut graft. Full text links |
| 136. | [Practical courses for students can not only improve the teaching quality but can also increase the attractiveness of orthopaedic and trauma surgery]Z Orthop Unfall. 2013 Aug;151(4):389-93. doi: 10.1055/s-0033-1350747. Epub 2013 Aug 20. [Article in German] AuthorsT Histing 1 , J Jung, D Wincheringer, J Ludwig, A Pizanis, T Pohlemann, M D Menger Affiliation
AbstractBackground: Students often complain about a lack of teaching of practical skills. This may be a cause for the low attractiveness of surgical disciplines. We therefore established a practical course to improve teaching quality to inspire the students for orthopedic and trauma surgery. Methods: The platforms of the course included the teaching and acquisition of suture techniques, arthroscopy and osteosynthesis techniques. A total of 119 students participated in 9 courses and performed a detailed evaluation. Results: The main motivation to participate was (i) to acquire practical skills (93 %), (ii) to learn about orthopaedic and trauma surgery (66 %) and (iii) to facilitate decision-making for the occupational choice (21 %). 94 % judged the quality of the course as "excellent", and all 119 participants indicated that they would recommend the course to other students. 43 of 45 students, who had not yet decided on their occupational choice, indicated that the course stimulated them for a career in orthopaedic and trauma surgery. Conclusion: This course not only can improve the teaching quality but also can increase the attractiveness of muskuloskeletal surgery. Georg Thieme Verlag KG Stuttgart · New York. Full text links |
| 137. | Emergency stabilization of the pelvic ring: Clinical comparison between three different techniquesInjury. 2013 Dec;44(12):1760-4. doi: 10.1016/j.injury.2013.07.009. Epub 2013 Aug 2. AuthorsA Pizanis 1 , T Pohlemann, M Burkhardt, E Aghayev, J H Holstein Affiliation
AbstractBackground: Emergency devices for pelvic ring stabilization include circumferential sheets, pelvic binders, and c-clamps. Our knowledge of the outcome of these techniques is currently based on limited information. Methods: Using the dataset of the German Pelvic Trauma Registry, demographic and injury-associated characteristics as well as the outcome of pelvic fracture patients after sheet, binder, and c-clamp treatment was compared. Outcome parameters included transfusion requirement of packed red blood cells, length of hospital stay, mortality, and incidence of lethal pelvic bleeding. Results: Two hundred seven of 6137 (3.4%) patients documented in the German Pelvic Trauma Registry between April 30th 2004 and January 19th 2012 were treated by sheets, binders, or c-clamps. In most cases, c-clamps (69%) were used, followed by sheets (16%), and binders (15%). The median age was significantly lower in patients treated with binders than in patients treated with sheets or c-clamps (26 vs. 47 vs. 42 years, p=0.01). Sheet wrapping was associated with a significantly higher incidence of lethal pelvic bleeding compared to binder or c-clamp stabilization (23% vs. 4% vs. 8%). No significant differences between the study groups were found in sex, fracture type, blood haemoglobin concentration, arterial blood pressure, Injury Severity Score, the incidence of additional pelvic packing and arterial embolization, need of red blood cell transfusion, length of hospitalisation, and mortality. Conclusions: The data suggest that emergency stabilization of the pelvic ring by binders and c-clamps is associated with a lower incidence of lethal pelvic bleeding compared to sheet wrapping. Level of evidence: Level III. Keywords: Bleeding control; C-clamp; Circumferential sheet; Pelvic binder; Pelvic fracture. Copyright © 2013 Elsevier Ltd. All rights reserved. Full text links |
| 138. | Rodent animal models of delayed bone healing and non-union formation: a comprehensive reviewEur Cell Mater. 2013 Jul 16:26:1-12; discussion 12-4. doi: 10.22203/ecm.v026a01. AuthorsP Garcia 1 , T Histing, J H Holstein, M Klein, M W Laschke, R Matthys, A Ignatius, B Wildemann, J Lienau, A Peters, B Willie, G Duda, L Claes, T Pohlemann, M D Menger Affiliation
Free article AbstractDespite the growing knowledge on the mechanisms of fracture healing, delayed healing and non-union formation remain a major clinical challenge. Animal models are needed to study the complex process of normal and impaired fracture healing and to develop new therapeutic strategies. Whereas in the past mainly large animals have been used to study normal and impaired fracture healing, nowadays rodent models are of increasing interest. New osteosynthesis techniques for rat and mice have been developed during the last years, which allowed for the first time stable osteosynthesis in these animals comparable to the standards in large animals and humans. Based on these new implants, different models in rat and mice have been established to study delayed healing and non-union formation. Although in humans the terms delayed union and non-union are well defined, in rodents definitions are lacking. However, especially in scientific studies clear definitions are necessary to develop a uniform scientific language and allow comparison of the results between different studies. In this consensus report, we define the basic terms "union", "delayed healing" and "non-union" in rodent animal models. Based on a review of the literature and our own experience, we further provide an overview on available models of delayed healing and non-union formation in rats and mice. We further summarise the value of different approaches to study normal and delayed fracture healing as well as non-union formation, and discuss different methods of data evaluation. Full text links |
| 139. | Bromelain down-regulates myofibroblast differentiation in an in vitro wound healing assayNaunyn Schmiedebergs Arch Pharmacol. 2013 Oct;386(10):853-63. doi: 10.1007/s00210-013-0890-z. Epub 2013 Jun 15. AuthorsKathrin Aichele 1 , Monika Bubel, Gunther Deubel, Tim Pohlemann, Martin Oberringer Affiliation
AbstractBromelain, a pineapple-derived enzyme mixture, is a widely used drug to improve tissue regeneration. Clinical and experimental data indicate a better outcome of soft tissue healing under the influence of bromelain. Proteolytic, anti-bacterial, anti-inflammatory, and anti-oedematogenic effects account for this improvement on the systemic level. It remains unknown, whether involved tissue cells are directly influenced by bromelain. In order to gain more insight into those mechanisms by which bromelain modulates tissue regeneration at the cellular level, we applied a well-established in vitro wound healing assay. Two main players of soft tissue healing--fibroblasts and microvascular endothelial cells--were used as mono- and co-cultures. Cell migration, proliferation, apoptosis, and the differentiation of fibroblasts to myofibroblasts as well as interleukin-6 were quantified in response to bromelain (36 × 10(-3) IU/ml) under normoxia and hypoxia. Bromelain attenuated endothelial cell and fibroblast proliferation in a moderate way. This proliferation decrease was not caused by apoptosis, rather, by driving cells into the resting state G0 of the cell cycle. Endothelial cell migration was not influenced by bromelain, whereas fibroblast migration was clearly slowed down, especially under hypoxia. Bromelain led to a significant decrease of myofibroblasts under both normoxic (from 19 to 12 %) and hypoxic conditions (from 22 to 15 %), coincident with higher levels of interleukin-6. Myofibroblast differentiation, a clear sign of fibrotic development, can be attenuated by the application of bromelain in vitro. Usage of bromelain as a therapeutic drug for chronic human wounds thus remains a very promising concept for the future. Full text links |
| 140. | Treatment for displaced proximal humerus fractures: comparison of interlocking plate fixation versus minimal invasive techniquesEur J Orthop Surg Traumatol. 2014 Jul;24(5):707-14. doi: 10.1007/s00590-013-1235-9. Epub 2013 Jun 1. AuthorsFelix Bachelier 1 , Antonius Pizanis, Julia Schwitalla, Tim Pohlemann, Dieter Kohn, Reiner Wirbel Affiliation
AbstractBackground and purpose: The functional results and the complications following interlocking plate fixation of displaced proximal humerus fractures should be evaluated and compared with those following minimal invasive fixation techniques. Patients and methods: Fifty patients (30 women, 20 men, mean age 62.7 (18-91) years) were treated for a displaced proximal humerus fracture using an interlocking plate fixation (PHILOS®) between 2003 and 2004. The mean follow-up time was 12 (9-36) months. Functional and radiographic results (Constant-Murley and Neer scores) were analyzed and compared with an equivalent historical control group of 53 patients operated for the same fracture types using minimal invasive techniques (K-wires and/or cannulated screws) between 1995 and 1997. According to the OTA/AO classification, there were 15 type A, 18 type B, and 17 type C fractures in the plate fixation group, and 23, 25, and 5 of these types in the control group, respectively. Results: The mean Neer score was 85.9, the mean Constant-Murley score 84, whereas 82.4 and 75.4 for the control group, respectively. Good and excellent results were seen in 78%, whereas in 70% in the control group. The results were dependent upon the fracture's type, sex, and patient's age. Complications were seen in 9 patients, whereas in 16 patients in the control group. Interpretation: Using an interlocking plate, the indication of fixation of displaced proximal humerus fractures had been expanded to type C fractures. The implant failure rate can be reduced. The functional results achieved are better compared with those following minimal invasive techniques. Full text links |
| 141. | Endostatin inhibits Callus remodeling during fracture healing in miceJ Orthop Res. 2013 Oct;31(10):1579-84. doi: 10.1002/jor.22401. Epub 2013 May 30. AuthorsJoerg H Holstein 1 , Bianca Karabin-Kehl, Claudia Scheuer, Patric Garcia, Tina Histing, Christoph Meier, Emanuel Benninger, Michael D Menger, Tim Pohlemann Affiliation
Free article AbstractInformation on the impact of endogenous anti-angiogenic factors on bone repair is limited. The hypothesis of the present study was endostatin, an endogenous inhibitor of angiogenesis, disturbs fracture healing. We evaluated this hypothesis in a closed femoral fracture model studying two groups of mice, one that was treated by a daily injection of 10 µg recombinant endostatin subcutaneously (n = 38) and a second one that received the vehicle for control (n = 37). Histomorphometric analysis showed a significantly increased callus formation in endostatin-treated animals at 2 and 5 weeks post-fracture. This was associated with a significantly higher callus tissue fraction of cartilage and fibrous tissue at 2 weeks and a significantly higher fraction of bone at 5 weeks post-fracture. Biomechanical testing revealed a significantly higher torsional stiffness in the endostatin group at 2 weeks. For both groups, we could demonstrate the expression of the endostatin receptor unit integrin alpha5 in endothelial cells, osteoblasts, osteoclasts, and chondrocytes at 2 weeks. Immunohistochemical fluorescence staining of CD31 showed a lower number of blood vessels in endostatin-treated animals compared to controls. The results of the present study indicate endostatin promotes soft callus formation but inhibits callus remodeling during fracture healing most probably by an inhibition of angiogenesis. Keywords: angiogenesis; endostatin; fracture healing; integrin alpha5; mice. Copyright © 2013 Orthopaedic Research Society. Full text links |
| 142. | Improvement of research quality in the fields of orthopaedics and trauma: a global perspectiveInt Orthop. 2013 Jul;37(7):1205-12. doi: 10.1007/s00264-013-1897-2. Epub 2013 May 21. AuthorsHangama C Fayaz 1 , Norbert Haas, James Kellam, Suthorn Bavonratanavech, Javad Parvizi, George Dyer, Tim Pohlemann, Jörg Jerosch, Karl-Josef Prommersberger, Hans Christoph Pape, Malcolm Smith, Marc Vrahas, Carsten Perka, Klaus Siebenrock, Bassem Elhassan, Christopher Moran, Jesse B Jupiter Affiliation
AbstractThe international orthopaedic community aims to achieve the best possible outcome for patient care by constantly modifying surgical techniques and expanding the surgeon's knowledge. These efforts require proper reflection within a setting that necessitates a higher quality standard for global orthopaedic publication. Furthermore, these techniques demand that surgeons acquire information at a rapid rate while enforcing higher standards in research performance. An international consensus exists on how to perform research and what rules should be considered when publishing a scientific paper. Despite this global agreement, in today's "Cross Check Era", too many authors do not give attention to the current standards of systematic research. Thus, the purpose of this paper is to describe these performance standards, the available choices for orthopaedic surgeons and the current learning curve for seasoned teams of researchers and orthopaedic surgeons with more than three decades of experience. These lead to provide an accessible overview of all important aspects of the topics that will significantly influence the research development as we arrive at an important globalisation era in orthopaedics and trauma-related research. Full text links |
| 143. | Osteitis pubis and adductor tendinopathy in athletes: a novel arthroscopic pubic symphysis curettage and adductor reattachmentArch Orthop Trauma Surg. 2013 Jul;133(7):1003-9. doi: 10.1007/s00402-013-1777-7. Epub 2013 May 21. AuthorsSascha Jörg Hopp 1 , Ulf Culemann, Jens Kelm, Tim Pohlemann, Antonius Pizanis Affiliation
AbstractIntroduction: Various surgical treatment options have been described in athletes with degenerative osteitis pubis who fail to respond to conservative treatment modalities. Although adductor longus tendinopathy often represents an additional pain generator in chronic groin pain associated with osteitis pubis, this has not been acknowledged in the surgical literature, to our knowledge. We present the results of a novel surgical technique for combined degenerative lesions of the pubic symphysis joint and the adjacent adductor longus tendon in a series of athletes with osteitis pubis. Methods: During 2009 and 2010, five competitive non-professional soccer players with considerable groin and pubic pain were referred to our clinic, after conservative therapy over a period of at least 12 months had failed. According to our clinical protocol for patients with groin pain, physical examination, pelvic radiographs and arthrography of the pubic symphysis to detect microlesions of the adjacent adductor longus tendons were performed. The patients diagnosed with degenerative osteitis pubis and concomitant lesion of the adductor longus origin were indicated for surgery. Surgery consisted of resection of the degenerative soft and bone tissue and subsequent reattachment with suture anchors. With regard to stability of the symphysis pubis, a two-portal arthroscopic curettage of the degenerative fibrocartilaginous disc tissue was performed. The patients were followed prospectively at medium term with assessment of general pain level (VAS score) and sport activity with pain (NIPPS score) pre- and postoperatively. Results: All patients recovered to full activity sports after an average period of 14.4 weeks. VAS and NIPPS scores markedly improved and overall satisfaction with the postoperative result was high. One intraoperative bleeding occurred, needing revision surgery. None of the patients developed pubic instability due to pubic symphysis curettage in the sequel. Conclusions: This novel surgical technique combines successfully stability-preserving arthroscopic pubic symphysis curettage with adductor debridement and reattachment in well-selected cases of athletes suffering from degenerative osteitis pubis and concomitant adductor pathology, being refractory to conservative treatment. Diligent preoperative evaluation of the specific pathology will lead to successful outcome. Full text links |
| 144. | Trauma registry record linkage: methodological approach to benefit from complementary data using the example of the German Pelvic Injury Register and the TraumaRegister DGU(®)BMC Med Res Methodol. 2013 Mar 5:13:30. doi: 10.1186/1471-2288-13-30. AuthorsMarkus Burkhardt 1 , Ulrike Nienaber, Joerg H Holstein, Ulf Culemann, Bertil Bouillon, Emin Aghayev, Thomas Paffrath, Marc Maegele, Tim Pohlemann, Rolf Lefering; TraumaRegister DGU(®); Pelvic Injury Register of the German Trauma Society Affiliation
AbstractBackground: In Germany, hospitals can deliver data from patients with pelvic fractures selectively or twofold to two different trauma registries, i.e. the German Pelvic Injury Register (PIR) and the TraumaRegister DGU(®) (TR). Both registers are anonymous and differ in composition and content. We describe the methodological approach of linking these registries and reidentifying twofold documented patients. The aim of the approach is to create an intersection set that benefit from complementary data of each registry, respectively. Furthermore, the concordance of data entry of some clinical variables entered in both registries was evaluated. Methods: PIR (4,323 patients) and TR (34,134 patients) data from 2004-2009 were linked together by using a specific match code including code of the trauma department, dates of admission and discharge, patient's age, and sex. Data entry concordance was evaluated using haemoglobin and blood pressure levels at emergency department arrival, Injury Severity Score (ISS), and mortality. Results: Altogether, 420 patients were identified as documented in both data sets. Linkage rates for the intersection set were 15.7% for PIR and 44.4% for TR. Initial fluid management for different Tile/OTA types of pelvic ring fractures and the patient's posttraumatic course, including intensive care unit data, were now available for the PIR population. TR is benefiting from clinical use of the Tile/OTA classification and from correlation with the distinct entity "complex pelvic injury." Data entry verification showed high concordance for the ISS and mortality, whereas initial haemoglobin and blood pressure data showed significant differences, reflecting inconsistency at the data entry level. Conclusions: Individually, the PIR and the TR reflect a valid source for documenting injured patients, although the data reflect the emphasis of the particular registry. Linking the two registries enabled new insights into care of multiple-trauma patients with pelvic fractures even when linkage rates were poor. Future considerations and development of the registries should be done in close bilateral consultation with the aim of benefiting from complementary data and improving data concordance. It is also conceivable to integrate individual modules, e.g. a pelvic fracture module, into the TR likewise a modular system in the future. Full text links |
| 145. | [Anterior approaches to the pelvic ring]Unfallchirurg. 2013 Mar;116(3):198-204. doi: 10.1007/s00113-012-2329-2. [Article in German] AuthorsS C Becker 1 , J H Holstein, A Pizanis, T Pohlemann Affiliation
AbstractAnterior approaches for the stabilization of anterior and also posterior B and C type instability of the pelvic ring were the standard procedures before minimally invasive percutaneous methods supported by image intensifiers or navigation devices were established. Anterior approaches are currently still of high relevance for difficult or impossible closed reductions in multiple trauma surgery where the patient must remain in a supine position. They are also used for stabilization of an increasing number of osteoporotic fractures in the elderly which are no longer only treated in specialized pelvic trauma centres. The anterior as well as the posterior part of the pelvic ring can be stabilized via various anterior approaches. A Pfannenstiel incision is appropriate for plating of ruptures of the pubic symphysis and can be extended to a modified Stoppa approach if necessary. Fractures of the iliac wings can be approached either laterally or less traumatically, via an anterolateral approach. The latter equates the lateral window of the ilioinguinal approach to the acetabulum, allows visualization of the entire sacroiliac joint and therefore stabilization of not only iliosacral luxation but also luxated fractures with a small iliac fragment. By a combination of the different approaches it is possible to simultaneously stabilize ventral and dorsal instabilities in type C fractures of the pelvic ring with a minimal amount of iatrogenic soft tissue trauma. Although the described anterior approaches are considered as simple exact knowledge of the endangered structures and general risks for each approach are essential for a safe exposure of the anatomical region addressed. Full text links |
| 146. | Reduced myofibroblast differentiation on femtosecond laser treated 316LS stainless steelMater Sci Eng C Mater Biol Appl. 2013 Mar 1;33(2):901-8. doi: 10.1016/j.msec.2012.11.018. Epub 2012 Nov 21. AuthorsMartin Oberringer 1 , Erhan Akman 2 , Juseok Lee 3 , Wolfgang Metzger 1 , Cagri Kaan Akkan 3 , Elif Kacar 2 , Arif Demir 4 , Hashim Abdul-Khaliq 5 , Norbert Pütz 6 , Gunther Wennemuth 6 , Tim Pohlemann 1 , Michael Veith 3 , Cenk Aktas 7 Affiliations
AbstractIn-stent restenosis is a common complication after stent surgery which leads to a dangerous wall narrowing of a blood vessel. Laser assisted patterning is one of the effective methods to modify the stent surface to control cell-surface interactions which play a major role in the restenosis. In this current study, 316 LS stainless steel substrates are structured by focusing a femtosecond laser beam down to a spot size of 50 μm. By altering the laser induced spot density three distinct surfaces (low density (LD), medium density (MD) and high density (HD)) were prepared. While such surfaces are composed of primary microstructures, due to fast melting and re-solidification by ultra-short laser pulses, nanofeatures are also observed as secondary structures. Following a detailed surface characterization (chemical and physical properties of the surface), we used a well-established co-culture assay of human microvascular endothelial cells and human fibroblasts to check the cell compatibility of the prepared surfaces. The surfaces were analyzed in terms of cell adherence, proliferation, cell morphology and the differentiation of the fibroblast into the myofibroblast, which is a process indicating a general fibrotic shift within a certain tissue. It is observed that myofibroblast proliferation decreases significantly on laser treated samples in comparison to non-treated ones. On the other hand endothelial cell proliferation is not affected by the surface topography which is composed of micro- and nanostructures. Such surfaces may be used to modify stent surfaces for prevention or at least reduction of restenosis. Copyright © 2012 Elsevier B.V. All rights reserved. Full text links |
| 147. | What are predictors for patients' quality of life after pelvic ring fractures?Clin Orthop Relat Res. 2013 Sep;471(9):2841-5. doi: 10.1007/s11999-013-2840-y. AuthorsJoerg H Holstein 1 , Antonius Pizanis, Daniel Köhler, Tim Pohlemann; Working Group Quality of Life After Pelvic Fractures Collaborators
Affiliation
AbstractBackground: Data from literature on predictors for patients' quality of life after pelvic ring fractures are conflicting and based on small study populations. Questions/purposes: We therefore evaluated predictors for health-related quality of life in patients with pelvic ring injuries at a minimum of 1 year postfracture. Methods: We surveyed 172 patients of the German Pelvic Trauma Registry admitted to four medical centers between February 3, 2004, and May 11, 2011. The median age of the followup cohort was 47 years (range, 8-88 years); 69 of 172 (40%) patients were female. Patients were characterized by a median Injury Severity Score of 17. There were 31 Tile Type A fractures (18%), 77 Type B fractures (45%), and 64 Type C fractures (37%). The incidence of complex fractures and multiple traumas was 34 of 172 (20%) and 116 of 172 (67%), respectively. One hundred twenty-five (73%) patients were treated operatively. We obtained the EQ-5D™ score to assess patients' health-related quality of life. For the analysis of predictors for quality of life, a multivariate linear regression model was built. The median followup was 3 years (range, 1-6 years). Results: The median EQ-5D™ score was 0.78 (interquartile limits, 0.63 and 1.00). Age, complex trauma, and surgery independently predicted the EQ-5D™ score. Conclusions: We conclude patients with higher age, complex trauma, and surgery had a higher likelihood for a reduced quality of life after pelvic ring injuries. Full text links |
| 148. | Delayed fracture healing in aged senescence-accelerated P6 miceJ Invest Surg. 2013 Feb;26(1):30-5. doi: 10.3109/08941939.2012.687435. Epub 2012 Dec 28. AuthorsTina Histing 1 , Swantje Kuntz, David Stenger, Claudia Scheuer, Patric Garcia, Joerg H Holstein, Moritz Klein, Tim Pohlemann, Michael D Menger Affiliation
AbstractBackground: Osteoporosis is characterized by poor bone quality. However, it is still controversially discussed whether osteoporosis compromises fracture healing. Herein, we studied whether the course of healing of a femur fracture is affected by osteoporosis or age. Methods: Using the senescence-accelerated osteoporotic mouse, strain P6 (SAMP6), and a closed femur fracture model, we studied the process of fracture healing in 5- and 10-month-old animals, including biomechanical, histomorphometric, and protein biochemical analysis. Results: In five-month-old osteoporotic SAMP6 mice, bending stiffness, callus size, and callus tissue distribution as well as the concentrations of the bone formation marker osteocalcin and the bone resorption markers tartrate-resistant acid phosphatase form 5b (TRAP) and deoxypyridinoline (DPD) did not differ from that of non-osteoporotic, senescence-resistant, strain 1 (SAMR1) controls. In contrast, femur fractures in 10-month-old SAMP6 mice showed a significantly reduced bending stiffness and an increased callus size compared to fractures in age-matched SAMR1 controls. This indicates a delayed fracture healing in advanced age SAMP6 mice. The delay of fracture healing was associated with higher concentrations of TRAP and DPD. Significant differences in osteocalcin concentrations were not found between SAMP6 animals and SAMR1 controls. Conclusion: In conclusion, the present study indicates that fracture healing in osteoporotic SAMP6 mice is not affected in five-month-old animals, but delayed in animals with an age of 10 months. This is most probably due to the increased osteoclast activity in advanced age SAMP6 animals. Full text links |
| 149. | Expansion and differentiation of human primary osteoblasts in two- and three-dimensional cultureBiotech Histochem. 2013 Feb;88(2):86-102. doi: 10.3109/10520295.2012.741262. Epub 2012 Dec 4. AuthorsW Metzger 1 , L Schimmelpfennig, B Schwab, D Sossong, N Dorst, M Bubel, A Görg, N Pütz, G Wennemuth, T Pohlemann, M Oberringer Affiliation
AbstractDespite the regenerative capability of bone, treatment of large defects often requires bone grafts. The challenge for bone grafting is to establish rapid and sufficient vascularization. Three-dimensional (3D) multicellular spheroids consisting of the relevant cell types can be used as "mini tissues" to study the complexity of angiogenesis. We investigated two-dimensional (2D) expansion, differentiation and characterization of primary osteoblasts as steps toward the establishment of 3D multicellular spheroids. Supplementation of cell culture medium with vitamin D(3) induces the osteocalcin expression of osteoblasts. An increased osteocalcin concentration of 10.8 ± 0.58 ng/ml could be measured after 19 days in supplemented medium. Vitamin D(3) has no influence on the expression of alkaline phosphatase or the deposition of calcium. Expression of these additional osteogenic markers requires addition of a cocktail of osteogenic factors that, conversely, have no influence on the expression of osteocalcin. Supplementation of the cell culture medium with both vitamin D(3) and a cocktail of osteogenic factors is recommended to produce an osteoblast phenotype that secretes osteocalcin, expresses alkaline phosphatase and deposits calcium. In such a supplemented medium, a mean osteocalcin concentration of 11.63 ± 4.85 ng/ml was secreted by the osteoblasts. Distinguishing osteoblasts and fibroblasts remains a challenge. Neither differentiated nor undifferentiated osteoblasts can be distinguished from fibroblasts by the expression of CD90, ED-A-fibronectin or α-smooth muscle actin; however, these cell types exhibit clear differences in their growth characteristics. Osteoblasts can be arranged as 3D spheroids by coating the bottom of the cell culture device with agarose. The cellular composition of 3D multicellular spheroids can be evaluated quantitatively using vital fluorescence labeling techniques. Spheroids are a promising tool for studying angiogenic and osteogenic phenomena in vivo and in vitro. Full text links |
| 150. | Excess dietary methionine does not affect fracture healing in miceMed Sci Monit. 2012 Dec;18(12):BR469-74. doi: 10.12659/msm.883590. AuthorsJoerg H Holstein 1 , Julia Schmalenbach, Markus Herrmann, Ilona Ölkü, Patric Garcia, Tina Histing, Wolfgang Herrmann, Michael D Menger, Tim Pohlemann, Lutz Claes Affiliation
AbstractBackground: An elevated serum concentration of homocysteine (hyperhomocysteinemia) has been shown to disturb fracture healing. As the essential amino acid, methionine, is a precursor of homocysteine, we aimed to investigate whether excess methionine intake affects bone repair. Material/methods: We analyzed bone repair in 2 groups of mice. One group was fed a methionine-rich diet (n=13), and the second group received an equicaloric control diet without methionine supplementation (n=12). Using a closed femoral fracture model, bone repair was analyzed by histomorphometry and biomechanical testing at 4 weeks after fracture. Blood was sampled to measure serum concentrations of homocysteine, the bone formation marker osteocalcin, and the bone resorption marker collagen I C-terminal crosslaps Results: Serum concentrations of homocysteine were significantly higher in the methionine group than in the control group, while serum markers of bone turnover did not differ significantly between the 2 groups. Histomorphometry revealed no significant differences in size and tissue composition of the callus between animals fed the methionine-enriched diet and those receiving the control diet. Accordingly, animals of the 2 groups showed a comparable bending stiffness of the healing bones. Conclusions: We conclude that excess methionine intake causes hyperhomocysteinemia, but does not affect fracture healing in mice. Full text links |
| 151. | [The pelvis]Unfallchirurg. 2012 Nov;115(11):956-7. doi: 10.1007/s00113-012-2311-z. [Article in German] AuthorAffiliation
No abstract available Full text links |
| 152. | Reduction and fixation capabilities of different plate designs for pubic symphysis disruption: a biomechanical comparisonInjury. 2013 Feb;44(2):183-8. doi: 10.1016/j.injury.2012.09.023. Epub 2012 Oct 12. AuthorsAntonius Pizanis 1 , Patric Garcia, Maike Santelmann, Ulf Culemann, Tim Pohlemann Affiliation
AbstractBackground: Typical stabilisation of pelvic open book injuries consists in plate fixation of the symphysis, leading to many different plate designs and procedures that have evolved. However, implant loosening and development of chronic instability are still evident and represent major complications after plate fixation of the symphysis. The aim of this study was to analyse reduction and fixation capabilities of different classical plate techniques with dynamic compression (DC), prebending or modern interlocking screws. Methods: Compression injuries (OTA B1.1) were simulated on synthetic composite pelvises. Sensor films placed in the disrupted symphysis allowed assessment of reduction and compression forces, as well as contact characteristics by implants at defined time points under static non loaded conditions. The commercially available steel plates used in our study differed in curved design, prebending and DC- or locking screw capabilities, as narrow large fragment (4.5) or small fragment plates (3.5). Results: DC procedure clearly increased the compressive force in the symphysis and improved the reduction by enhanced contact areas. These effects were preserved to the end of the experiments only when the plates were prebended (10°). Anatomically contoured and prebended 3.5 plates had a similar effect, but the contact area was even more pronounced. Best results were observed using the "3.5 symphyseal plate" with DC-effect medially and locking screws laterally. Purely interlocking screw plates by themselves allowed an optimal contact area, yet failed to preserve the initial compressive reduction force. Conclusions: The experimental results suggest a biomechanical advantage in using prebended plates for symphysis fixation compared to non-bended plates. Best results with regard to compression and increased contact area can be achieved by anatomically contoured plates with combined DC and locking screw capabilities. These findings are of special interest in pelvic surgery for choosing the right implant in severe displacements, obese patients and symphysiodesis techniques. Copyright © 2012 Elsevier Ltd. All rights reserved. Full text links |
| 153. | Soft tissue fibroblasts from well healing and chronic human wounds show different rates of myofibroblasts in vitroMol Biol Rep. 2013 Feb;40(2):1721-33. doi: 10.1007/s11033-012-2223-6. Epub 2012 Oct 14. AuthorsFlorian Schwarz 1 , Martina Jennewein, Monika Bubel, Joerg H Holstein, Tim Pohlemann, Martin Oberringer Affiliation
AbstractDue to an increasing life expectancy in western countries, chronic wound treatment will be an emerging challenge in the next decades. Because therapies are improving slowly appropriate diagnostic tools enabling the early prediction of the healing success remain to be developed. We used a well-established in vitro assay in combination with the analysis of 27 cytokines to discriminate between fibroblasts from chronic (n = 6) and well healing (n = 8) human wounds. Proliferation and migration of the cells as well as their response to hypoxia and their behaviour in co-culture with microvascular endothelial cells were analyzed. Myofibroblast differentiation, a time-limited essential process of regular wound healing, was also quantified. Besides weaker proliferation and migration significantly higher rates of myofibroblasts were detected in chronic wounds. With respect to the cytokine release, there was a clear trend within the group of chronic wound fibroblasts, which were releasing interferon-γ, monocyte chemotactic protein-1, granulocyte-macrophage colony stimulating factor and basic fibroblast growth factor in higher amounts than fibroblasts from healing wounds. Although the overall response of both groups of fibroblasts to hypoxia and to the contact with endothelial cells was similar, especially chronic wound fibroblasts seemed to benefit from the endothelial interaction during hypoxia and displayed better migration characteristics. The study shows (1) that the assay can identify specific features of fibroblasts derived from different human wounds and (2) that wound fibroblasts are varying in their response to the chosen parameters. Thus, current therapeutic approaches and individual healing prediction might benefit from this assay. Full text links |
| 154. | Acute management and outcome of multiple trauma patients with pelvic disruptionsCrit Care. 2012 Aug 22;16(4):R163. doi: 10.1186/cc11487. AuthorsMarkus Burkhardt, Ulrike Nienaber, Antonius Pizanis, Marc Maegele, Ulf Culemann, Bertil Bouillon, Sascha Flohé, Tim Pohlemann, Thomas Paffrath; TraumaRegister DGU; German Pelvic Injury Register of the Deutsche Gesellschaft für Unfallchirurgie
AbstractIntroduction: Data on prehospital and trauma-room fluid management of multiple trauma patients with pelvic disruptions are rarely reported. Present trauma algorithms recommend early hemorrhage control and massive fluid resuscitation. By matching the German Pelvic Injury Register (PIR) with the TraumaRegister DGU (TR) for the first time, we attempt to assess the initial fluid management for different Tile/OTA types of pelvic-ring fractures. Special attention was given to the patient's posttraumatic course, particularly intensive care unit (ICU) data and patient outcome. Methods: A specific match code was applied to identify certain patients with pelvic disruptions from both PIR and TR anonymous trauma databases, admitted between 2004 and 2009. From the resulting intersection set, a retrospective analysis was done of prehospital and trauma-room data, length of ICU stay, days of ventilation, incidence of multiple organ dysfunction syndrome (MODS), sepsis, and mortality. Results: In total, 402 patients were identified. Mean ISS was 25.9 points, and the mean of patients with ISS ≥ 16 was 85.6%. The fracture distribution was as follows: 19.7% type A, 29.4% type B, 36.6% type C, and 14.3% isolated acetabular and/or sacrum fractures. The type B/C, compared with type A fractures, were related to constantly worse vital signs that necessitated a higher volume of fluid and blood administration in the prehospital and/or the trauma-room setting. This group of B/C fractures were also related to a significantly higher presence of concomitant injuries and related to increased ISS. This was related to increased ventilation and ICU stay, increased rate of MODS, sepsis, and increased rate of mortality, at least for the type C fractures. Approximately 80% of the dead had sustained type B/C fractures. Conclusions: The present study confirms the actuality of traditional trauma algorithms with initial massive fluid resuscitation in the recent therapy of multiple trauma patients with pelvic disruptions. Low-volume resuscitation seems not yet to be accepted in practice in managing this special patient entity. Mechanically unstable pelvic-ring fractures type B/C (according to the Tile/OTA classification) form a distinct entity that must be considered notably in future trauma algorithms. Full text links |
| 155. | Management of hemodynamic unstable patients "in extremis" with pelvic ring fracturesActa Chir Orthop Traumatol Cech. 2012;79(3):193-202. AuthorsA Gänsslen 1 , F Hildebrand, T Pohlemann Affiliation
AbstractThe hemodynamic status in patients with pelvic ring injuries is a major prognostic factor of an immediate mortality risk. Especially, patients "in extremis" are of high risk to die. This patient group is characterized by absent vital signs or being in severe shock with initial systolic blood pressure .70 mm Hg and/or requiring mechanical resuscitation or catecholamines despite >12 blood transfusions within the first two hours after admission. The sources of pelvic bleeding is in approximately 80-90% of venous origin and relevant arterial bleeding accounts for 10-20%. Important parts of the initial treatment treatment concept include mechanical pelvic ring stabilization combined with hemorrhage control concepts. Mechanical stabilization is performed non-invasively by pelvic binder application or invasively by classical anterior pelvic fixation or posterior pelvic C-clamp, depending on the local available resources. In patients "in extremis" the concept of direct extraperitoneal pelvic packing is recommended, whereas in moderately unstable patients or in patients where persistant hemodynamic instability occurs despite shock therapy and mechanical stabilization and pelvic packing, arterial injury is ruled out by angiography followed by selected embolization of pelvic vessels. |
| 156. | Angioembolization for pelvic hemorrhage control: results from the German pelvic injury registerJ Trauma Acute Care Surg. 2012 Sep;73(3):679-84. doi: 10.1097/TA.0b013e318253b5ba. AuthorsOliver Hauschild 1 , Emin Aghayev, Johanna von Heyden, Peter C Strohm, Ulf Culemann, Tim Pohlemann, Norbert P Suedkamp, Hagen Schmal Affiliation
AbstractBackground: Hemorrhage from pelvic vessels is a potentially lethal complication of pelvic fractures. There is ongoing controversy on the ideal treatment strategy for patients with pelvic hemorrhage. The aim of the study was to analyze the role of angiography and subsequent embolization in patients with pelvic fractures and computed tomography scan-proven vascular injuries. Methods: The data from the prospective multicenter German pelvic injury registry were analyzed. Of 5,040 patients with pelvic fractures, 152 patients with associated vascular injuries were identified. Patients undergoing angioembolization (n = 17) were compared with those undergoing conventional measures for hemorrhage control (n = 135) with regard to demographic and physiologic parameters, fracture type distribution, and treatment measures. Outcome measures were mortality, requirement for blood transfusions, complications, and hospital length of stay. Results: Embolization and nonembolization groups were comparable with regard to age, sex, Injury Severity Score, Hannover Polytrauma Score, initial hemoglobin levels, blood pressure, fracture distribution, and conventional measures. Blood transfusion requirement was significantly prolonged in the embolization group. This resulted in a higher adult respiratory distress syndrome incidence and a tendency toward increased multiple organ failure rate in this group. There was no significant difference in overall mortality rate when compared with the nonembolization group (17.6% vs. 32.6%, respectively; p = 0.27). None of the patients undergoing embolization died from exsanguination when compared with 20.6% in the nonembolization group (p = 0.038). Conclusion: Angioembolization alongside with conventional measures is an effective complementary means for hemorrhage control in patients sustaining pelvic fracture-related vascular lesions. It might prove even more effective when performed early enough to avoid prolonged blood transfusion requirement. Further studies without the mentioned limitations of the study are desired. Level of evidence: Therapeutic study, level IV. Full text links |
| 157. | Screw- versus plate-fixation strength of acetabular anterior column fractures: a biomechanical studyJ Trauma Acute Care Surg. 2012 Jun;72(6):1664-70. doi: 10.1097/TA.0b013e3182463b45. AuthorsFlorian Gras 1 , Ivan Marintschev, Christoph E Schwarz, Gunther O Hofmann, Tim Pohlemann, Ulf Culemann Affiliation
AbstractBackground: The standard for operative treatment of acetabular fractures is open reduction and plate fixation. Recently, screw fixation-only methods through less invasive approaches are reported, but biomechanical data are missing. Questions posed in this study are (1) is the static fixation strength of different screw types equivalent to the standard plate fixation for anterior column fractures of the acetabulum? and (2) does the placement of an additional screw in the infra-acetabular corridor increase the fixation strength independent of the used implant? Methods: Three groups of different screws (group II, titanium; group III, stainless steel; and group IV, biodegradable Poly-L-Lactid) were compared with the standard plate fixation (group I) in Synbone pelves with custom-made anterior column fractures. Six pelvises per group were axial loaded with six cycles of 800 N, twice with and without an additional placed infra-acetabular screw. Results: The fixation strength of titanium screws was equivalent to the standard plate fixation. The stainless steel and Poly-L-Lactid screw fixation strengths were equivalent to each other but inferior to the aforementioned. The additional placement of an infra-acetabular screw significantly increased the fracture fixation strength, independent of the used implant. Conclusion: Screw fixation is a promising alternative approach for the stabilization of noncomminuted acetabular fractures of the anterior column with equivalent fixation strength to the standard plate fixation. The additional placement of an infra-acetabular screw significantly increases the fracture fixation independent of the used implant and should be considered for acetabular fractures with separation of both columns. Level of evidence: Therapeutic study, level IV. Copyright © 2012 by Lippincott Williams & Wilkins. Full text links |
| 158. | A new model to analyze metaphyseal bone healing in miceJ Surg Res. 2012 Dec;178(2):715-21. doi: 10.1016/j.jss.2012.04.007. Epub 2012 Apr 27. AuthorsTina Histing 1 , Moritz Klein, Andrea Stieger, David Stenger, Roland Steck, Romano Matthys, Joerg H Holstein, Patric Garcia, Tim Pohlemann, Michael D Menger Affiliation
AbstractBackground: Despite the increasing clinical problems with metaphyseal fractures, most experimental studies investigate the healing of diaphyseal fractures. Although the mouse would be the preferable species to study the molecular and genetic aspects of metaphyseal fracture healing, a murine model does not exist yet. Using a special locking plate system, we herein introduce a new model, which allows the analysis of metaphyseal bone healing in mice. Methods: In 24 CD-1 mice the distal metaphysis of the femur was osteotomized. After stabilization with the locking plate, bone repair was analyzed radiologically, biomechanically, and histologically after 2 (n=12) and 5 wk (n=12). Additionally, the stiffness of the bone-implant construct was tested biomechanically ex vivo. Results: The torsional stiffness of the bone-implant construct was low compared with nonfractured control femora (0.23 ± 0.1 Nmm/°versus 1.78 ± 0.15 Nmm/°, P<0.05). The cause of failure was a pullout of the distal screw. At 2 wk after stabilization, radiological analysis showed that most bones were partly bridged. At 5 wk, all bones showed radiological union. Accordingly, biomechanical analyses revealed a significantly higher torsional stiffness after 5 wk compared with that after 2 wk. Successful healing was indicated by a torsional stiffness of 90% of the contralateral control femora. Histological analyses showed new woven bone bridging the osteotomy without external callus formation and in absence of any cartilaginous tissue, indicating intramembranous healing. Conclusion: With the model introduced herein we report, for the first time, successful metaphyseal bone repair in mice. The model may be used to obtain deeper insights into the molecular mechanisms of metaphyseal fracture healing. Copyright © 2012 Elsevier Inc. All rights reserved. Full text links |
| 159. | Pantoprazole, a proton pump inhibitor, delays fracture healing in miceCalcif Tissue Int. 2012 Jun;90(6):507-14. doi: 10.1007/s00223-012-9601-x. Epub 2012 Apr 24. AuthorsT Histing 1 , D Stenger, C Scheuer, W Metzger, P Garcia, J H Holstein, M Klein, T Pohlemann, M D Menger Affiliation
AbstractProton pump inhibitors (PPIs), which are widely used in the treatment of dyspeptic problems, have been shown to reduce osteoclast activity. There is no information, however, on whether PPIs affect fracture healing. We therefore studied the effect of the PPI pantoprazole on callus formation and biomechanics during fracture repair. Bone healing was analyzed in a murine fracture model using radiological, biomechanical, histomorphometric, and protein biochemical analyses at 2 and 5 weeks after fracture. Twenty-one mice received 100 mg/kg body weight pantoprazole i.p. daily. Controls (n = 21) received equivalent amounts of vehicle. In pantoprazole-treated animals biomechanical analysis revealed a significantly reduced bending stiffness at 5 weeks after fracture compared to controls. This was associated with a significantly lower amount of bony tissue within the callus and higher amounts of cartilaginous and fibrous tissue. Western blot analysis showed reduced expression of the bone formation markers bone morphogenetic protein (BMP)-2, BMP-4, and cysteine-rich protein (CYR61). In addition, significantly lower expression of proliferating cell nuclear antigen indicated reduced cell proliferation after pantoprazole treatment. Of interest, the reduced expression of bone formation markers was associated with a significantly diminished expression of RANKL, indicating osteoclast inhibition. Pantoprazole delays fracture healing by affecting both bone formation and bone remodeling. Full text links |
| 160. | Balloon tibioplasty: a useful tool for reduction of tibial plateau depression fracturesJ Orthop Trauma. 2012 Jul;26(7):e88-93. doi: 10.1097/BOT.0b013e31823a8dc8. AuthorsAntonius Pizanis 1 , Patric Garcia, Tim Pohlemann, Markus Burkhardt Affiliation
AbstractReduction of the articular surface in displaced tibial plateau fractures is still challenging and may result in joint incongruence, leading to posttraumatic arthrosis. Conventional techniques use bone tamps and similar instruments, which can increase the surgical trauma due to their size. "Balloon tibioplasty" is a novel minimally invasive technique for the reduction of depressed tibial plateau fractures. We successfully applied an inflatable balloon, commercially available from kyphoplasty, to elevate the depressed articular fragments. This technique allowed for reduction of the depressed tibial plateau fragment without classic fenestration of the tibia, thereby minimizing surgical trauma. Furthermore, under fluoroscopic control, optimal centering of the expanding tibioplasty balloon allows a widespread and continuously increasing reduction force to the fracture area. After fluoroscopy or arthroscopic confirmation of reduction of the articular surface, the cavity resulting from tibioplasty was filled with ceramic bone cement through small incisions and fractures were fixed with a small fragment locking T-plate (3.5 mm). Balloon tibioplasty was applied in 5 patients with displaced tibial plateau fractures (OTA type B2/3). No intra- or postoperative complications were observed. This new technique may be a useful tool to facilitate the reduction of select depressed tibial fractures in the future. Full text links |
| 161. | The treatment of patients with severe and multiple traumatic injuriesDtsch Arztebl Int. 2012 Feb;109(6):102-8. doi: 10.3238/arztebl.2012.0102. Epub 2012 Feb 10. AuthorsEdmund A M Neugebauer 1 , Christian Waydhas, Sven Lendemans, Dieter Rixen, Michaela Eikermann, Tim Pohlemann Affiliation
AbstractBackground: The care of severely and multiply injured patients is an interdisciplinary challenge. The only existing German-language guideline up to now has been the S1-guideline issued in 2002 by the German Society for Trauma Surgery (Deutsche Gesellschaft für Unfallchirurgie, DGU). In this article, we present a new, comprehensive, evidence and consensus based S3-guideline for the treatment of severely and multiply injured patients in the pre-hospital and early in-hospital phases which has been developed with the aim of structural and procedural quality optimization. Its implementation should lower these patients' mortality and improve their quality of life. Methods: The guideline was developed by a panel consisting of 18 delegates from 11 specialty societies under the lead of the DGU, with designated coordinators for each of three phases of treatment: the pre-hospital phase, the emergency-room phase, and the emergency surgery phase. The key questions to be answered were determined by vote, and then the relevant literature (in English and German, 1995-2010) was systematically searched and evaluated. Key recommendations with explanatory texts were formulated and agreed upon in a nominal group process (NGP) with five consensus conferences and three further Delphi rounds. Results: 264 recommendations were issued: 66 for the pre-hospital phase, 102 for the emergency-room phase, and 96 for the emergency surgery phase. The three phases were subcategorized according to organizational and anatomical considerations. Topics of major emphasis were, in the pre-hospital phase, the establishment and implementation of correct priorities for treatment; in the emergency-room phase, the creation of clear structures and processes; and, in the emergency surgery phase, the avoidance of secondary injury (i.e., the principle of damage control). Conclusion: This guideline can only improve outcomes if it is implemented in routine practice. Aside from the guideline itself, the DGU trauma network (www.dgu-traumanetzwerk.de) has issued a set of directions as an aid to its implementation. Comment in
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| 162. | How to ensure the survival of the surgeon-scientist? The Homburg ProgramLangenbecks Arch Surg. 2012 Apr;397(4):619-22. doi: 10.1007/s00423-012-0925-9. Epub 2012 Feb 24. AuthorsMichael D Menger 1 , Martin K Schilling, Hans-Joachim Schäfers, Tim Pohlemann, Matthias W Laschke Affiliation
AbstractBackground: Academic surgery requires competence in research, teaching, and patient care. Because of the increasing complexity of both surgical research and clinical surgery, and additional skills necessary for adequate patient care, including economics, management, and organization, it becomes more and more difficult to provide an attractive education for surgeon-scientists. This has resulted in a dramatic decline in the number of surgeon-scientists in the past and alarms us to systematically restructure our research training system. Discussion: We herein introduce a program involving the clinical departments of surgery, trauma surgery, and cardiac-thoracic surgery as well as a surgical research institution. The program allows the clinical departments to sharpen their overall research profile and facilitates the establishment of competent working groups, guaranteeing long-term research activities on a high scientific level. The program involves both surgical residents and medical students, who will represent our future generation of academic surgeons, ensuring the survival of the surgeon-scientist. Full text links |
| 163. | What are predictors of mortality in patients with pelvic fractures?Clin Orthop Relat Res. 2012 Aug;470(8):2090-7. doi: 10.1007/s11999-012-2276-9. AuthorsJoerg H Holstein 1 , Ulf Culemann, Tim Pohlemann; Working Group Mortality in Pelvic Fracture Patients Collaborators
Affiliation
AbstractBackground: Our knowledge of factors influencing mortality of patients with pelvic ring injuries and the impact of associated injuries is currently based on limited information. Questions/purposes: We identified the (1) causes and time of death, (2) demography, and (3) pattern and severity of injuries in patients with pelvic ring fractures who did not survive. Methods: We prospectively collected data on 5340 patients listed in the German Pelvic Trauma Registry between April 30, 2004 and July 29, 2011; 3034 of 5340 (57%) patients were female. Demographic data and parameters indicating the type and severity of injury were recorded for patients who died in hospital (nonsurvivors) and compared with data of patients who survived (survivors). The median followup was 13 days (range, 0-1117 days). Results: A total of 238 (4%) patients died a median of 2 days after trauma. The main cause of death was massive bleeding (34%), predominantly from the pelvic region (62% of all patients who died because of massive bleeding). Fifty-six percent of nonsurvivors and 43% of survivors were male. Nonsurvivors were characterized by a higher incidence of complex pelvic injuries (32% versus 8%), less isolated pelvic ring fractures (13% versus 49%), lower initial blood hemoglobin concentration (6.7 ± 2.9 versus 9.8 ± 3.0 g/dL) and systolic arterial blood pressure (77 ± 27 versus 106 ± 24 mmHg), and higher injury severity score (ISS) (35 ± 16 versus 15 ± 12). Conclusion: Patients with pelvic fractures who did not survive were characterized by male gender, severe multiple trauma, and major hemorrhage. Level of evidence: Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence. Full text links |
| 164. | Increased exercise after stable closed fracture fixation does not affect fracture healing in miceJ Biomech. 2012 Apr 30;45(7):1299-304. doi: 10.1016/j.jbiomech.2012.01.028. Epub 2012 Feb 14. AuthorsJ H Holstein 1 , S C Becker, M Fiedler, C Scheuer, P Garcia, T Histing, M Klein, M D Menger, T Pohlemann Affiliation
AbstractPurpose: The aim of the present study was to evaluate the systemic biological effect of increased exercise on bone repair after stable fracture fixation. Methods: Two groups of SKH-1h mice were studied. Animals of the first group (n=36) were housed in cages supplied with a running wheel, while mice of the second group (n=37) were housed in standard cages for control. Using a closed femur fracture model, bone repair was analysed by histomorphometry and biomechanical testing at 2 and 5 weeks. At 2 weeks, we additionally evaluated the expression of the proliferation marker PCNA (proliferating cell nuclear antigen) and the angiogenic and osteogenic growth factor VEGF (vascular endothelial growth factor). To standardise the mechanical conditions in the fracture gap, we used an intramedullary compression screw for stable fracture fixation. Results: Each mouse of the exercise group run a mean total distance of 23.5 km after 2 weeks and 104.3 km after 5 weeks. Histomorphometric analysis of the size and tissue composition of the callus could not reveal significant differences between mice undergoing exercise and controls. Accordingly, biomechanical testing showed a comparable torsional stiffness, peak rotation angle, and load at failure of the healing bones in the two groups. The expression of PCNA and VEGF did also not differ between mice of the exercise group and controls. Conclusion: We conclude that increased exercise does not affect bone repair after stable fracture fixation. Copyright © 2012 Elsevier Ltd. All rights reserved. Full text links |
| 165. | Initial experience using a pelvic emergency simulator to train reduction in blood lossClin Orthop Relat Res. 2012 Aug;470(8):2098-103. doi: 10.1007/s11999-012-2272-0. AuthorsTim Pohlemann 1 , Ulf Culemann, Joerg H Holstein Affiliation
AbstractBackground: Because the average exposure of surgeons to pelvic injuries with life-threatening hemorrhage is decreasing, training opportunities are necessary to prepare surgeons for the rare but highly demanding emergency situations. We have developed a novel pelvic emergency simulator to train surgeons in controlling blood loss. Questions/purposes: We (1) described the design and use of the simulator; and (2) determined whether the simulator correctly identified proper and improper mechanical stabilization and bleeding control. Methods: The device contained two tube systems. The tubes of the first system were passed through the disrupted sacroiliac joint and the symphysis. By reduction (manual traction on the leg) and compression (application of the C-clamp) of the disrupted pelvis, the tubes were pinched by the synthetic bones leading to a stop of simulated blood flow through the tubes of the first system. The tubes of the second system ended in a foam representing the presacral and paravesical venous plexus. By correct preperitoneal packing, the flow into the foam was stopped. Simulated bleeding was monitored by quantifying flow out of a fluid reservoir and flow into fluid samplers. Results: The pelvic emergency simulator has been used for eight training sessions since 2002. Bleeding control by packing was achieved after 6 ± 3 minutes. Total simulated blood loss during the training session was 1296 ± 892 mL. Conclusions: Our data suggest the simulator can be used as a tool to train surgeons to reduce blood loss in severe pelvic ring injuries. Full text links |
| 166. | Biomechanical comparison of different acetabular plate systems and constructs--the role of an infra-acetabular screw placement and use of locking platesInjury. 2012 Apr;43(4):470-4. doi: 10.1016/j.injury.2011.11.009. Epub 2012 Jan 18. AuthorsIvan Marintschev 1 , Florian Gras, Christoph E Schwarz, Tim Pohlemann, Gunther O Hofmann, Ulf Culemann Affiliation
AbstractIntroduction: The aim of this study was the direct comparison of the static fixation strength of two common plate systems: MPS (Matta Pelvic System) and LPPS (Low Profile Plate System). Furthermore the role of a modified screw placement with addressing the infra-acetabular corridor and the use of locking screws were evaluated. Materials and methods: Custom made anterior column fractures in artificial SYNBONE pelves were fixed with different acetabular plates (group I: MPS, group II: LPPS none locking and group III: LPPS locking). Each pelvis was tested twice, with the additionally placed infra-acetabular lag screw [+] first, followed by a repeated measurement without the infra-acetabular screw [-]. Six pelves per group were tested under static loading with six cycles up to 800N, each. The fracture displacement was measured in the weight bearing dome using an ultrasound based Zebris-3D-Motion Analyzer. Results: The MPS-plate had a less fixation strength compared to the LPPS-plate (mean±SD of maximum fracture displacement [mm] in group I vs. group II=0.63±0.02 vs. 0.37±0.02, p<0.05). The locking feature did not increase the fracture fixation strength (mean±SD of maximum fracture displacement [mm] in group II vs. group III: 0.37±0.02 vs. 0.37±0.03; ns). The infra-acetabular screw significantly reduces the maximum fracture displacement in all groups, independent of the plate systems ([Delta%] in group I=50; group II=63 and group III=40; p<0.05 each). Conclusion: The LPPS-plate performed superior fixation strength for anterior column fractures compared to the MPS-plate. The locking plate modality did not reduce the maximum fracture displacement, whereas the additional infra-acetabular screw placement actually doubles the fracture fixation strength independent of the used plate system. Copyright © 2011 Elsevier Ltd. All rights reserved. Full text links |
| 167. | Temporal and spatial vascularization patterns of unions and nonunions: role of vascular endothelial growth factor and bone morphogenetic proteinsJ Bone Joint Surg Am. 2012 Jan 4;94(1):49-58. doi: 10.2106/JBJS.J.00795. AuthorsP Garcia 1 , A Pieruschka, M Klein, A Tami, T Histing, J H Holstein, C Scheuer, T Pohlemann, M D Menger Affiliation
AbstractBackground: Failure of fracture-healing with nonunion is a major clinical problem. Angiogenesis is closely linked to bone regeneration, but the role of angiogenesis in nonunion formation remains unclear. Because established nonunions are well vascularized, we hypothesized that lack of vascular endothelial growth factor (VEGF) expression and vascularization during the early time course of fracture-healing determine nonunion formation. Methods: In seventy-two CD-1 mice, a femoral osteotomy with a gap size of 1.80 mm (nonunion group) or a gap size of 0.25 mm (union group) was created and stabilized by a pin-clip technique. Healing was analyzed after three, seven, fourteen, twenty-one, twenty-eight, and seventy days by micro-computed tomography and histomorphometry. Vascularization was determined in different healing zones by immunohistochemical staining of PECAM-1 (platelet-endothelial cell adhesion molecule). Additional animals were analyzed after seven, fourteen, and twenty-one days with Western blot analysis of VEGF, bone morphogenetic protein (BMP)-2, and BMP-4 expression. Results: Micro-computed tomography and histomorphometry showed complete bone-bridging in the union group, whereas animals in the nonunion group showed atrophic nonunion formation. Vascularization increased from day 3 to day 7 in both groups, with a subsequent decrease after fourteen days. However, overall vascularization did not differ between unions and nonunions over time. It is of interest that vascularization within the endosteal healing zone was even higher in nonunions than in unions after fourteen days. Expression of VEGF was significantly higher in nonunions, while expression of BMP-2 and 4 and proliferating cell nuclear antigen were found significantly reduced compared with unions. Conclusions: Because vascularization during the early time course of fracture-healing was not impaired despite the failure of bone-healing in nonunions, we rejected our hypothesis and accepted the null hypothesis that nonunion formation is not due to failure of VEGF-mediated angiogenesis. Failure of fracture-healing was associated with a decreased expression of BMP-2 and 4 and a disturbed ratio of angiogenic to osteogenic growth factors, which may be responsible for nonunion. Clinical relevance: Because the intrinsic angiogenic response during nonunion formation was sufficient for adequate vascularization, treatment strategies for nonunions should focus on the stimulation of osteogenesis rather than on the stimulation of angiogenesis. Full text links |
| 168. | Effects of pelvic volume changes on retroperitoneal and intra-abdominal pressure in the injured pelvic ring: a cadaveric modelJ Trauma. 2011 Sep;71(3):585-90; discussion 590. doi: 10.1097/TA.0b013e318224cd62. AuthorsDaniel Köhler 1 , Richard Martin Sellei, Aaron Sop, Ivan S Tarkin, Roman Pfeifer, Robert Leo Garrison, Tim Pohlemann, Hans Christoph Pape Affiliation
AbstractBackground: Pelvic ring injuries can be associated with severe blood loss and hemodynamic instability. The increase in pelvic volume in disrupted pelvic ring injuries is thought to cause accumulation of large volumes of blood in the retroperitoneal cavity. Extra abdominal compression for reduction of the pelvic ring may affect intrapelvic pressure. We examined the effects of pelvic volume changes on retroperitoneal pressures (RPP) and intra-abdominal pressures (IAPs) in the intact and unstable pelvic ring. Methods: In a cadaver study, unembalmed human torsos were used. Infusion lines were placed adjacent to the sacroiliac joint in the retroperitoneum and in the abdominal cavity. IAP and RPP measurements were performed with sequential infusion of crystalloid solution in 1,000 mL increments. Measurements were performed in the intact pelvic ring and after induction of unilateral and bilateral instability by disruption of the pubic symphysis, the sacroiliac joints, the sacrotuberous ligaments, and sacrospinous ligaments. Results: After infusion of 4,000 mL of saline, we observed a pressure increase in the retroperitoneal cavity (RPP) of 19.64 mm Hg ± 6.43 mm Hg in the intact pelvis, 5.22 mm Hg ± 1.74 mm Hg in unilateral instability, and 2.78 mm Hg ± 0.57 mm Hg in bilateral instability. The RPP response in the case of instability decreased significantly (p = 0.019). The IAP showed a change of 4.63 mm Hg ± 2.64 mm Hg in the intact pelvis, 3.88 mm Hg ± 1.84 mm Hg in unilateral instability, and 2.30 mm Hg ± 0.36 mm Hg in bilateral instability. Further infusion revealed a close association between RAPs and IAPs. Conclusions: In the intact pelvis, RPP rises rapidly with increasing volume. The results seem to support the idea that disrupted pelvic ring fractures may lead to a significant volume uptake that is reversed during reduction. Full text links |
| 169. | Erythropoietin stimulates bone formation, cell proliferation, and angiogenesis in a femoral segmental defect model in miceBone. 2011 Nov;49(5):1037-45. doi: 10.1016/j.bone.2011.08.004. Epub 2011 Aug 9. AuthorsJ H Holstein 1 , M Orth, C Scheuer, A Tami, S C Becker, P Garcia, T Histing, P Mörsdorf, M Klein, T Pohlemann, M D Menger Affiliation
AbstractThe glycoprotein erythropoietin (EPO) has been demonstrated to stimulate fracture healing. The aim of the present study was to investigate the effect of EPO treatment on bone repair in a femoral segmental defect model. Bone repair was analyzed in mice which were treated by EPO (500IE/kg/d intraperitoneally; n=38) and in mice which received the vehicle for control (n=40). Two and 10 weeks after creating a 1.8mm femoral segmental defect, bone repair was studied by micro-CT, histology, and Western blot analysis. At 10 weeks, micro-CT and histomorphometric analyses showed a significantly higher bridging rate of the bone defects in EPO-treated animals than in controls. This was associated by a significantly higher bone volume within the segmental defects of the EPO-treated animals. At 2 weeks, Western blot analyses revealed a significantly higher expression of vascular endothelial growth factor (VEGF) in EPO-treated animals compared to controls. Accordingly, the number of blood vessels was significantly increased in the EPO group at 2 weeks. At 10 weeks, we found a significantly higher expression of proliferating cell nuclear antigen (PCNA) in EPO-treated animals when compared to controls. Western blot analyses showed no significant differences between the groups in the expression of the endothelial and inducible nitric oxide synthases (eNOS and iNOS) and the angiopoietin receptor Tie-2. Immunohistochemistry confirmed the results of the Western blot analyses, demonstrating a significantly higher number of VEGF- and PCNA-positive cells in EPO-treated animals than in controls at 2 and 10 weeks, respectively. We conclude that EPO is capable of stimulating bone formation, cell proliferation and VEGF-mediated angiogenesis in a femoral segmental defect model. Copyright © 2011 Elsevier Inc. All rights reserved. Full text links |
| 170. | [Acetabular fractures in the elderly. Outcome of open reduction and internal fixation]Unfallchirurg. 2011 Aug;114(8):655-62. doi: 10.1007/s00113-011-2021-y. [Article in German] AuthorsG Tosounidis 1 , U Culemann, M Bauer, J H Holstein, P Garcia, R Kurowski, A Pizanis, E Aghayev, T Pohlemann Affiliation
AbstractThe aim of this study was to analyze the clinical outcome and incidence of hip arthritis in elderly patients with acetabular fractures. Because of poor bone quality in the elderly, even a low-energy trauma may lead to an acetabular fracture. An anatomical reconstruction of the acetabulum is necessary to achieve sufficient stability also for a potential hip arthroplasty. So far, there is very limited information on the outcome of acetabular fractures in the elderly. During a period of 6 years (2001-2006), 48 patients older than 60 years were admitted to our department with an acetabular fracture. Thirty-nine patients were treated operatively and nine patients non-operatively. Twenty-nine operatively treated patients were followed up. Nineteen of them were assessed using EQ-5D, SF-12 and Merle d'Aubigné questionnaires in addition to their clinical examination. Ten other surgical patients were only examined using the questionnaires. Of the 29 patients that were followed up, 5 underwent total hip arthroplasty due to secondary post-traumatic hip arthritis after open reduction and internal fixation (ORIF). The range of motion of the operated hip was comparable to that of the non-operated contralateral side. However, the internal rotation was found to be slightly decreased at the operated side when compared to the non-operated contralateral side. Merle d'Aubigné score and physical and mental SF-12 score components as well as quality of life were better in patients treated with ORIF compared to those patients that were treated by secondary hip arthroplasty. Regarding the different treatment strategies (ORIF vs primary hip arthroplasty vs non-operative treatment) of acetabular fractures in the elderly, data from the literature are conflicting. Our results indicate that ORIF represents a good treatment option for acetabular fractures in the elderly. In patients that did not develop secondary hip arthritis, a good clinical outcome and quality of life was documented. Full text links |
| 171. | Small animal bone healing models: standards, tips, and pitfalls results of a consensus meetingBone. 2011 Oct;49(4):591-9. doi: 10.1016/j.bone.2011.07.007. Epub 2011 Jul 19. AuthorsT Histing 1 , P Garcia, J H Holstein, M Klein, R Matthys, R Nuetzi, R Steck, M W Laschke, T Wehner, R Bindl, S Recknagel, E K Stuermer, B Vollmar, B Wildemann, J Lienau, B Willie, A Peters, A Ignatius, T Pohlemann, L Claes, M D Menger Affiliation
AbstractSmall animal fracture models have gained increasing interest in fracture healing studies. To achieve standardized and defined study conditions, various variables must be carefully controlled when designing fracture healing experiments in mice or rats. The strain, age and sex of the animals may influence the process of fracture healing. Furthermore, the choice of the fracture fixation technique depends on the questions addressed, whereby intra- and extramedullary implants as well as open and closed surgical approaches may be considered. During the last few years, a variety of different, highly sophisticated implants for fracture fixation in small animals have been developed. Rigid fixation with locking plates or external fixators results in predominantly intramembranous healing in both mice and rats. Locking plates, external fixators, intramedullary screws, the locking nail and the pin-clip device allow different degrees of stability resulting in various amounts of endochondral and intramembranous healing. The use of common pins that do not provide rotational and axial stability during fracture stabilization should be discouraged in the future. Analyses should include at least biomechanical and histological evaluations, even if the focus of the study is directed towards the elucidation of molecular mechanisms of fracture healing using the largely available spectrum of antibodies and gene-targeted animals to study molecular mechanisms of fracture healing. This review discusses distinct requirements for the experimental setups as well as the advantages and pitfalls of the different fixation techniques in rats and mice. Copyright © 2011 Elsevier Inc. All rights reserved. Full text links |
| 172. | [Benchmarking of university trauma centers in Germany. Research and teaching]Unfallchirurg. 2011 Jul;114(7):639-44. doi: 10.1007/s00113-011-2057-z. [Article in German] AuthorsF Gebhard 1 , M Raschke, S Ruchholtz, R Meffert, I Marzi, T Pohlemann, N Südkamp, C Josten, H Zwipp Affiliation
AbstractBenchmarking is a very popular business process and meanwhile is used in research as well. The aim of the present study is to elucidate key numbers of German university trauma departments regarding research and teaching. The data set is based upon the monthly reports given by the administration in each university. As a result the study shows that only well-known parameters such as fund-raising and impact factors can be used to benchmark university-based trauma centers. The German federal system does not allow a nationwide benchmarking. Full text links |
| 173. | The liquid overlay technique is the key to formation of co-culture spheroids consisting of primary osteoblasts, fibroblasts and endothelial cellsCytotherapy. 2011 Sep;13(8):1000-12. doi: 10.3109/14653249.2011.583233. Epub 2011 May 27. AuthorsWolfgang Metzger 1 , Daniela Sossong, Annick Bächle, Norbert Pütz, Gunther Wennemuth, Tim Pohlemann, Martin Oberringer Affiliation
AbstractBackground aims: The 3-dimensional (3-D) culture of various cell types reflects the in vivo situation more precisely than 2-dimensional (2-D) cell culture techniques. Spheroids as 3-D cell constructs have been used in tumor research for a long time. They have also been used to study angiogenic mechanisms, which are essential for the success of many tissue-engineering approaches. Several methods of forming spheroids are known, but there is a lack of systematic studies evaluating the performance of these techniques. Methods: We evaluated the performance of the hanging drop technique, carboxymethyl cellulose technique and liquid overlay technique to form both mono- and co-culture spheroids consisting of primary osteoblasts, fibroblasts and endothelial cells. The performance of the three techniques was evaluated in terms of rate of yield and reproducibility. The size of the generated spheroids was determined systematically. Results: The liquid overlay technique was the most suitable for generating spheroids reproducibly. The rate of yield for this technique was between 60% and 100% for monoculture spheroids and 100% for co-culture spheroids. The size of the spheroids could be adjusted easily and precisely by varying the number of seeded cells organized in one spheroid. The formation of co-culture spheroids consisting of three different cell types was possible. Conclusions: Our results show that the most suitable technique for forming spheroids can vary from the chosen cell type, especially if primary cells are used. Co-culture spheroids consisting of three different cell types will be used to study angiogenic phenomena in further studies. Full text links |
| 174. | Increased osteoblast and osteoclast activity in female senescence-accelerated, osteoporotic SAMP6 mice during fracture healingJ Surg Res. 2012 Jun 15;175(2):271-7. doi: 10.1016/j.jss.2011.03.052. Epub 2011 Apr 19. AuthorsTina Histing 1 , David Stenger, Swantje Kuntz, Claudia Scheuer, Andrea Tami, Patric Garcia, Joerg H Holstein, Moritz Klein, Tim Pohlemann, Michael D Menger Affiliation
AbstractBackground: Previous studies have shown that fracture healing depends on gender and that in females, ovariectomy-induced osteoporosis impairs the healing process. There is no information, however, whether the alteration of fracture healing in osteoporosis also depends on gender. Materials and methods: Therefore, we herein studied fracture healing in female and male senescence-accelerated osteoporotic mice, strain P6 (SAMP6), including biomechanical, histomorphometric, and protein biochemical analysis. Results: Bending stiffness was reduced in male and female SAMP6 mice compared with senescence-resistant strain 1 (SAMR1) controls. This was associated with elevated serum concentrations of tartrate-resistent acid phosphatase form 5b (TRAP) in both female and male SAMP6 mice. Callus size, however, was significantly larger in female SAMP6 mice compared with male SAMP6 mice and female SAMR1 controls. This indicates a delayed remodeling process in female SAMP6 mice. The delay of callus remodeling in female SAMP6 mice was associated with a significantly higher osteoprotegerin (OPG) callus tissue expression and increased serum concentrations of osteocalcin (OC) and deoxypyridinoline (DPD), indicating elevated osteoblast and osteoclast activities. Conclusion: The present study shows that remodeling during fracture healing in female, but not in male, SAMP6 mice is delayed, most probably due to an increased osteoblast and osteoclast activity. Copyright © 2012 Elsevier Inc. All rights reserved. Full text links |
| 175. | High bone concentrations of homocysteine are associated with altered bone morphology in humansBr J Nutr. 2011 Aug;106(3):378-82. doi: 10.1017/S0007114511000304. Epub 2011 Apr 27. AuthorsJoerg H Holstein 1 , Markus Herrmann, Christina Splett, Wolfgang Herrmann, Patric Garcia, Tina Histing, Moritz Klein, Karsten Kurz, Thomas Siebel, Tim Pohlemann, Michael D Menger Affiliation
AbstractAccumulation of homocysteine and S-adenosylhomocysteine in bone has been shown to be associated with reduced bone quality in rats. The aim of the present study was to investigate whether high bone concentrations of homocysteine and S-adenosylhomocysteine as well as a low methylation capacity are related to an impaired bone morphology in humans. Concentrations of homocysteine and its precursors S-adenosylhomocysteine and S-adenosylmethionine were measured in femoral bone samples of eighty-two males and females (age 71 (SD 8) years) who underwent elective hip arthroplasty. Cancellous bone structure was analysed by histomorphometry. In addition, blood was sampled to measure serum concentrations of homocysteine. Results of bone and serum analyses were grouped for individuals with high or low bone concentrations of homocysteine, S-adenosylhomocysteine and S-adenosylmethionine, as well as for individuals with a high or a low methylation capacity, which is indicated by a low or a high S-adenosylhomocysteine:S-adenosylmethionine ratio (n 41, each). Histomorphometry showed a higher trabecular separation and a lower trabecular thickness, trabecular number and trabecular area in individuals with high bone concentrations of homocysteine and S-adenosylhomocysteine compared with individuals with low bone concentrations of homocysteine and S-adenosylhomocysteine. There was no association between the S-adenosylhomocysteine:S-adenosylmethionine ratio and bone morphology. It was found that 48 % of bone homocysteine was bound to the collagen of the extracellular bone matrix. Blood analyses demonstrated a significant correlation between serum and bone homocysteine. The results of the present study indicate an association between altered bone morphology and elevated bone concentrations of homocysteine and S-adenosylhomocysteine, but not between altered bone morphology and methylation capacity. Full text links |
| 176. | Survival trends and predictors of mortality in severe pelvic trauma: estimates from the German Pelvic Trauma Registry InitiativeInjury. 2011 Oct;42(10):997-1002. doi: 10.1016/j.injury.2011.03.053. Epub 2011 Apr 22. AuthorsTim Pohlemann 1 , Dirk Stengel, Georgios Tosounidis, Heinrich Reilmann, Fabian Stuby, Uli Stöckle, Andreas Seekamp, Hagen Schmal, Andreas Thannheimer, Francis Holmenschlager, Axel Gänsslen, Pol Maria Rommens, Thomas Fuchs, Friedel Baumgärtel, Ivan Marintschev, Gert Krischak, Stephan Wunder, Harald Tscherne, Ulf Culemann Affiliation
AbstractStudy objective: To determine longitudinal trends in mortality, and the contribution of specific injury characteristics and treatment modalities to the risk of a fatal outcome after severe and complex pelvic trauma. Methods: We studied 5048 patients with pelvic ring fractures enrolled in the German Pelvic Trauma Registry Initiative between 1991 and 1993, 1998 and 2000, and 2004 and 2006. Complete datasets were available for 5014 cases, including 508 complex injuries, defined as unstable fractures with severe peri-pelvic soft tissue and organ laceration. Multivariable mixed-effects logistic regression analysis was employed to evaluate the impact of demographic, injury- and treatment-associated variables on all-cause in-hospital mortality. Results: All-cause in-hospital mortality declined from 8% (39/466) in 1991 to 5% (33/638) in 2006. Controlling for age, Injury Severity Score, pelvic vessel injury, the need for emergency laparotomy, and application of a pelvic clamp, the odds ratio (OR) per annum was 0.94 (95% confidence interval [CI] 0.91-0.96). However, the risk of death did not decrease significantly in patients with complex injuries (OR 0.98, 95% CI 0.93-1.03). Raw mortality associated with this type of injury was 18% (95% CI 9-32%) in 2006. Conclusion: In contrast to an overall decline in trauma mortality, complex pelvic ring injuries remain associated with a significant risk of death. Awareness of this potentially life-threatening condition should be increased amongst trauma care professionals, and early management protocols need to be implemented to improve the survival prognosis. Copyright © 2011 Elsevier Ltd. All rights reserved. Full text links |
| 177. | [Operative treatment of the peripelvic Morel-Lavallée lesion]Oper Orthop Traumatol. 2011 Feb;23(1):15-20. doi: 10.1007/s00064-010-0003-9. [Article in German] AuthorsD Köhler 1 , T Pohlemann Affiliation
AbstractObjective: Evacuation of hematoma, hemostasis, reduction of dead space by vacuum systems for minimization of secondary complications, such as full skin necrosis, deep infections, and secondary wound closure. Indications: Morel-Lavallée lesion (MLL), all larger epifascial hematomas. Contraindications: None. Surgical technique: Central longitudinal incision, detection of the extent of the hematoma, transection of the full length of the lesion, hemostasis, debridement, application of vacuum systems, secondary wound closure, or splitskin coverage. Postoperative management: Vacuum therapy must be continued until secretions are less than 30 ml/24 hours. Negative bacterial culture before wound closure is imperative. Daily change of wound dressings, frequent control of inflammation parameters. Weight bearing until consolidation of soft tissue. Results: Operative treatment of the MLL with vacuum systems is a relatively new concept, and results on larger collectives have not been published yet. A total of 8 patients in our hospital underwent vacuum therapy after sustaining a MLL, 5 of them with concomitant instability of the pelvic ring. Emergency stabilization and initiation of vacuum therapy were performed on the day of admission. Three patients had initially positive bacterial colonialization. Duration of vacuum therapy was 8.5 days (range 4-14 days). Dressings were changed every 2.6 days (range 1-4 days). While 6 wounds could be closed secondarily, 2 needed split skin coverage. Complications were not observed. Vacuum therapy facilitates wound management and helps reduce bacterial colonialization. It has also been proved to have a beneficial effect on qualitative and quantitative granulation. Full text links |
| 178. | Exercise enhances angiogenesis during bone defect healing in miceJ Orthop Res. 2011 Jul;29(7):1086-92. doi: 10.1002/jor.21352. Epub 2011 Jan 21. AuthorsJoerg H Holstein 1 , Steven C Becker, Martin Fiedler, Claudia Scheuer, Patric Garcia, Tina Histing, Moritz Klein, Tim Pohlemann, Michael D Menger Affiliation
Free article AbstractThe aim of the present study was to investigate the effect of exercise on angiogenesis during bone defect healing in mice. We evaluated angiogenesis during cranial bone defect healing by intravital fluorescence microscopy (IVM) at days 0-21. To characterize the type of bone repair, we performed additional histomorphometric analyses at days 3-15. IVM was conducted in mice, which were housed in cages supplied with running wheels (exercise group; n=7) and compared to IVM results of mice, which were housed in cages without running wheels (controls; n=7). In the exercise group, we additionally performed correlation analyses between results of the IVM and the running distance. IVM showed an accelerated decrease of bone defect area in the exercise group compared to the control group. This was associated with a significantly higher blood vessel diameter in animals undergoing exercise at days 9 and 12 and a significant correlation between running distance and blood vessel density at day 9 (r = 0.74). Histomorphometry showed osseous bridging of the defect at day 9. The newly woven bone was covered by a neo-periosteum containing those blood vessels, which were visible by IVM. We conclude that exercise accelerates bone defect healing and stimulates angiogenesis during bore repair. Copyright © 2011 Orthopaedic Research Society. Full text links |
| 179. | Sildenafil accelerates fracture healing in miceJ Orthop Res. 2011 Jun;29(6):867-73. doi: 10.1002/jor.21324. Epub 2011 Jan 18. AuthorsTina Histing 1 , Kerstin Marciniak, Claudia Scheuer, Patric Garcia, Joerg H Holstein, Moritz Klein, Romano Matthys, Tim Pohlemann, Michael D Menger Affiliation
Free article AbstractSildenafil, a cyclic guanosine monophosphate (cGMP)-dependent phospodiesterase-5 inhibitor, has been shown to be a potent stimulator of angiogenesis through upregulation of pro-angiogenic factors and control of cGMP concentration. Herein, we determined whether sildenafil also influences angiogenic growth factor expression and bone formation during the process of fracture healing. Bone healing was studied in a murine closed femur fracture model using radiological, biomechanical, histomorphometric, and protein biochemical analysis at 2 and 5 weeks after fracture. Thirty mice received 5 mg/kg body weight sildenafil p.o. daily. Controls (n = 30) received equivalent amounts of vehicle. After 2 weeks of fracture healing sildenafil significantly increased osseous fracture bridging, as determined radiologically and histologically. This resulted in an increased biomechanical stiffness compared to controls. A smaller callus area with a slightly reduced amount of cartilaginous tissue indicated an accelerated healing process. After 5 weeks the differences were found blunted, demonstrating successful healing in both groups. Western blot analysis showed a significantly higher expression of the pro-angiogenic and osteogenic cysteine-rich protein (CYR) 61, confirming the increase of bone formation. We show for the first time that sildenafil treatment accelerates fracture healing by enhancing bone formation, most probably by a CYR61-associated pathway. Copyright © 2011 Orthopaedic Research Society. Full text links |
| 180. | Changes in epidemiology and treatment of pelvic ring fractures in Germany: an analysis on data of German Pelvic Multicenter Study Groups I and III (DGU/AO)Acta Chir Orthop Traumatol Cech. 2010;77(6):450-6. AuthorsG Tosounidis 1 , J H Holstein, U Culemann, F Holmenschlager, F Stuby, T Pohlemann Affiliation
AbstractThe diagnosis and treatment of pelvic ring injuries is demanding. Therefore, standardized classifications characterizing the stability and severity of pelvic ring fractures are essential to define clear algorithms for the treatment of these injuries. The first part of this article provides an overview of the etiology and classification of pelvic ring injuries. We recommend the AO classification to assess the stability of pelvic ring fractures. This classification includes 3 types of pelvic ring fractures: stable fractures (type A), fractures with only rotational instability (type B), and fractures with complete (rotational and translational) instability. To describe the severity of the injury, pelvic ring fractures can be classified as plain pelvic fractures, which include fractures with osteoligamentous instability, but without significant concomitant injuries to the soft tissue, versus complex pelvic fractures, which are combined with severe peripelvic soft tissue lesions.While plain pelvic fractures allow thorough clinical and radiological diagnostics, complex pelvic traumata represent a life threatening situation for the patient, which needs immediate emergency measures. In the second part of the this review we present current data of the German Pelvic Multicenter Study III (DGU/AO) on the epidemiology and treatment of pelvic ring injuries deriving from a study population of more than 3000 patients. In addition, we compare the present data with those of the German Pelvic Multicenter Study I and highlight changes in the epidemiology and treatment of pelvic ring fractures during the past decades. Taken together, we could observe an increasing number of elderly patients sustaining pelvic ring fractures.Regarding the treatment of pelvic ring fractures we found a rising use of external fixators and SI screws, while the number of laparotomies has markedly decreased. |
| 181. | Infra-acetabular corridor--technical tip for an additional screw placement to increase the fixation strength of acetabular fracturesJ Trauma. 2011 Jan;70(1):244-6. doi: 10.1097/TA.0b013e3181f45f91. AuthorsUlf Culemann 1 , Ivan Marintschev, Florian Gras, Tim Pohlemann Affiliation
No abstract available Full text links |
| 182. | Intravital microscopic studies of angiogenesis during bone defect healing in mice calvariaInjury. 2011 Aug;42(8):765-71. doi: 10.1016/j.injury.2010.11.020. Epub 2010 Dec 14. AuthorsJ H Holstein 1 , S C Becker, M Fiedler, P Garcia, T Histing, M Klein, M W Laschke, M Corsten, T Pohlemann, M D Menger Affiliation
AbstractPurpose: Due to the great availability of specific antibodies, gene-targeted animals and knockout strains, mouse models came into the focus of musculoskeletal research. Herein, we introduce a calvarian defect model in mice that allows the repetitive analysis of blood vessel formation during bone repair by intravital microscopy. Methods: The right parietal calvaria of 20 adult CD-1 mice were exposed by skin excision. Under continuous irrigation, a circular defect (Ø0.75 mm) was drilled into the calvarium without penetrating the inner cortical shell. A circular glass (Ø12 mm; thickness 0.15 mm) was fixed by two microscrews (M1; length 2mm) to cover the bone defect. Angiogenesis was analysed by intravital microscopy at days 0, 3, 6, 9, 12, 15, 18 and 21. In addition, bone repair was evaluated by histomorphometry at days 3, 6, 9 and 15. Immunohistochemical stainings for the angiogenic growth factor vascular endothelial growth factor (VEGF) and the cell proliferation marker proliferating cell nuclear antigen (PCNA) were performed to assess angiogenic and proliferative activity during healing of the calvarian defect. Results: Histomorphometry showed a typical pattern of intramembranous bone repair. Osseous bridging of the defect was observed at day 9. This was associated with the formation of a neo-periosteum, which covered the new woven bone and contained a dense network of newly formed blood vessels. At day 9, particularly cells of the neo-periosteum showed intense staining for VEGF, whilst PCNA-positive staining was found mainly in osteoblasts. At day 15, the major fraction of fibrous tissue was replaced by bone undergoing extensive remodelling. Intravital microscopy revealed an increase of vascular density between days 3 and 15. Blood vessel diameters showed an increase between days 3 and 9 and a subsequent decrease between days 9 and 21. Conclusions: The present calvarian defect model provides a powerful tool to evaluate the process of angiogenesis during intramembranous bone repair in mice. Copyright © 2010 Elsevier Ltd. All rights reserved. Full text links |
| 183. | Operative treatment of the peripelvic Morel-Lavallée lesionOper Orthop Traumatol. 2010 Dec 10. doi: 10.1007/s00064-010-9025-6. Online ahead of print. AuthorsDaniel Köhler 1 , Tim Pohlemann Affiliation
AbstractOBJECTIVE : Evacuation of haematoma, haemostasis, reduction of dead space by vacuum systems for minimisation of secondary complications as full skin necrosis and deep infections, secondary wound closure. INDICATIONS : Morel-Lavallée lesion (MLL). All larger epifascial haematomas. CONTRAINDICATIONS : None. SURGICAL TECHNIQUE : Central longitudinal incision, detection of the subcutanous extent of the haematoma, transection of the full length of the lesion, haemostasis, debridement, application of vacuum systems, secondary wound closure or splitskin coverage. POSTOPERATIVE MANAGEMENT : Vacuum therapy must be continued until secretions are less than 30 ml/24 h. Negative bacterial culture before wound closure is imperative. Daily change of wound dressings, frequent controls of inflammation parameters. Weight bearing until consolidation of soft tissue. RESULTS : Operative treatment of the MLL with vacuum systems is a relatively new concept and results on larger collectives have not been published yet. Eight patients in our hospital underwent vacuum therapy after sustaining a MLL, five of them with concomitant instability of the pelvic ring. Emergency stabilisation and initiation of vacuum therapy were performed on day of admission. Three patients had initially positive bacterial colonialisation. Duration of vacuum therapy was 8,5 days (4-14). Dressings were changed every 2,6 days (1-4). Six wounds could be closed secondarily, two needed split skin coverage. Complications were not observed. Vacuum therapy facilitates wound management and helps to reduce bacterial colonialisation. It has also been proved to have a beneficial effect on qualitative and quantitative granulation. Full text links |
| 184. | [Update Unfallchirurgie]Unfallchirurg. 2010 Dec;113(12):974-5. doi: 10.1007/s00113-010-1924-3. [Article in German] AuthorAffiliation
No abstract available Full text links |
| 185. | Melatonin impairs fracture healing by suppressing RANKL-mediated bone remodelingJ Surg Res. 2012 Mar;173(1):83-90. doi: 10.1016/j.jss.2010.08.036. Epub 2010 Sep 21. AuthorsTina Histing 1 , Christina Anton, Claudia Scheuer, Patric Garcia, Joerg H Holstein, Moritz Klein, Romano Matthys, Tim Pohlemann, Michael D Menger Affiliation
AbstractBackground: Melatonin, the major pineal hormone, is known to regulate distinct physiologic processes. Previous studies have suggested that it supports skeletal growth and bone formation, most probably by inhibiting bone resorption. There is no information, however, whether melatonin affects fracture healing. We therefore studied in a mouse femur fracture model the influence of melatonin on callus formation and biomechanics during fracture healing. Methods and materials: Thirty CD-1 mice received 50 mg/kg body weight melatonin i.p. daily during the entire 2-wk or 5-wk observation period. Controls (n = 30) received equivalent amounts of vehicle. Bone healing was studied by radiological, biomechanical, histomorphometrical, and protein biochemical analyses at 2 and 5 wk after fracture. Results: Biomechanical analysis at 2 wk after fracture healing showed a significantly lower bending stiffness in melatonin-treated animals compared with controls. A slightly higher amount of cartilage tissue and a significantly larger callus size indicated a delayed remodeling process after melatonin treatment. Western blot analysis showed a significantly reduced expression of receptor activator of nuclear factor-κB ligand (RANKL) and collagen I after melatonin treatment. The reduced expression of RANKL was associated with a diminished number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts within the callus of the newly formed bone. Conclusions: Because bone resorption is an essential requirement for adequate remodeling during fracture healing, we conclude that melatonin impairs fracture healing by suppressing bone resorption through down-regulation of RANKL-mediated osteoclast activation. Copyright © 2012 Elsevier Inc. All rights reserved. Full text links |
| 186. | In vivo gait analysis in a mouse femur fracture modelJ Biomech. 2010 Dec 1;43(16):3240-3. doi: 10.1016/j.jbiomech.2010.07.019. Epub 2010 Sep 15. AuthorsT Histing 1 , A Kristen, C Roth, J H Holstein, P Garcia, R Matthys, M D Menger, T Pohlemann Affiliation
AbstractAlthough the mouse has become a preferred species for molecular studies on fracture healing, gait analysis after fracture fixation and during bone healing has not yet been performed in mice. Herein, we introduce a novel technique for gait analysis in mice and report the change of motion pattern after fracture and fixation. A standardized femur fracture was stabilized by a common pin. The non-fractured tibia was additionally marked with a pin, allowing continuous analysis of the tibio-femoral angle by digital video-radiography. Dynamic gait analysis was performed at day fourteen after surgery in a radio-opaque running wheel. Fracture fixation resulted in a significantly reduced range and maximum of the tibio-femoral angle compared to non-fractured controls. This was associated with a significantly reduced stride length. Because stride frequency was slightly increased and, thus, stride time diminished, stride velocity was not significantly reduced compared to controls. Thus, our study demonstrates distinct alterations of the gait of mice at 2 weeks after femur fracture and stabilization. Our results support the need of gait analysis in fracture healing studies to assess the animals' well-being. Copyright © 2010 Elsevier Ltd. All rights reserved. Full text links |
| 187. | Erythropoietin ameliorates the reduced migration of human fibroblasts during in vitro hypoxiaJ Physiol Biochem. 2011 Mar;67(1):1-13. doi: 10.1007/s13105-010-0043-5. Epub 2010 Sep 4. AuthorsStephanie Breit 1 , Monika Bubel, Tim Pohlemann, Martin Oberringer Affiliation
AbstractErythropoietin promotes the formation of granulation tissue when administered to soft tissue wounds and it was shown to be most effective under tissue hypoxia. However, the action of erythropoietin on the cellular level is not well understood. In order to get a better insight into these processes, an in vitro wound healing assay was applied. Two main players of soft tissue healing-fibroblasts and microvascular endothelial cells-were used as mono- and co-cultures, subsequently inflicting in vitro wounds. Cell migration, proliferation, the differentiation of fibroblasts to myofibroblasts, and the release of vascular endothelial cell growth factor A and angiogenin were quantified in response to hypoxia and erythropoietin (5 IU/ml). Erythropoietin supplementation did neither affect proliferation nor migration of endothelial cells and fibroblasts under normoxia. Under hypoxia, the reduced fibroblast migration was ameliorated by erythropoietin. This effect coincided with an attenuated release of vascular endothelial growth factor A, whereas angiogenin release was unaffected by erythropoietin. The in vitro model applied in this study may represent an adequate approximation to certain aspects of the in vivo status of soft tissue regeneration and the results might serve to interpret the in vivo efficiency of erythropoietin at the cellular level: Erythropoietin has different impacts on the cells in normoxia and hypoxia. Its positive influence on fibroblast migration during hypoxia seems to support the strategies of applying erythropoietin in those chronic wounds, which exhibit fibroblastic dysfunction although good vascularisation is present. Full text links |
| 188. | Adhesion of fibroblasts on micro- and nanostructured surfaces prepared by chemical vapor deposition and pulsed laser treatmentBiofabrication. 2010 Sep;2(3):035001. doi: 10.1088/1758-5082/2/3/035001. Epub 2010 Jul 12. AuthorsM Veith 1 , O C Aktas, W Metzger, D Sossong, H Ullah Wazir, I Grobelsek, N Pütz, G Wennemuth, T Pohlemann, M Oberringer Affiliation
AbstractThe development of micro- and nanostructured surfaces which improve the cell-substrate interaction is of great interest in today's implant applications. In this regard, Al/Al2O3 bi-phasic nanowires were synthesized by chemical vapor deposition of the molecular precursor (tBuOAlH2)2. Heat treatment of such bi-phasic nanowires with short laser pulses leads to micro- and nanostructured Al2O3 surfaces. Such surfaces were characterized by scanning electron microscopy (SEM), electron dispersive spectroscopy and x-ray photoelectron spectroscopy. Following the detailed material characterization, the prepared surfaces were tested for their cell compatibility using normal human dermal fibroblasts. While the cells cultivated on Al/Al2O3 bi-phasic nanowires showed an unusual morphology, cells cultivated on nanowires treated with one and two laser pulses exhibited morphologies similar to those observed on the control substrate. The highest cell density was observed on surfaces treated with one laser pulse. The interaction of the cells with the nano- and microstructures was investigated by SEM analysis in detail. Laser treatment of Al/Al2O3 bi-phasic nanowires is a fast and easy method to fabricate nano- and microstructured Al2O3-surfaces for studying cell-surface interactions. It is our goal to develop a biocompatible Al2O3-surface which could be used as a coating material for medical implants exhibiting a cell selective response because of its specific physical landscape and especially because it promotes the adhesion of osteoblasts while minimizing the adhesion of fibroblasts. Full text links |
| 189. | Low dose erythropoietin stimulates bone healing in miceJ Orthop Res. 2011 Feb;29(2):165-72. doi: 10.1002/jor.21219. Epub 2010 Aug 25. AuthorsP Garcia 1 , V Speidel, C Scheuer, M W Laschke, J H Holstein, T Histing, T Pohlemann, M D Menger Affiliation
Free article AbstractBeyond its classical role in regulation of erythropoiesis, erythropoietin (EPO) has been shown to exert protective and regenerative actions in a variety of non-hematopoietic tissues. However, little is known about potential actions in bone regeneration. To analyze fracture healing in mice, a femoral 0.25 mm osteotomy gap was stabilized with a pin-clip technique. Animals were treated with 500 U EPO/kg bw per day or with vehicle only. After 2 and 5 weeks, fracture healing was analyzed biomechanically, radiologically and histologically. Expression of PCNA and NFκB was examined by Western blot analysis. Vascularization was analyzed by immunohistochemical staining of PECAM-1. Circulating endothelial progenitor cells were measured by flow-cytometry. Herein, we demonstrate that EPO-treatment significantly accelerates bone healing in mice. This is indicated by a significantly greater biomechanical stiffness and a higher radiological density of the periosteal callus at 2 and 5 weeks after fracture and stabilization. Histological analysis demonstrated significantly more bone and less cartilage and fibrous tissue in the periosteal callus. Endosteal vascularization was significantly increased in EPO-treated animals when compared to controls. The number of circulating endothelial progenitor cells was significantly greater in EPO-treated animals. The herein shown acceleration of healing by EPO may represent a promising novel treatment strategy for fractures with delayed healing and non-union formation. Copyright © 2010 Orthopaedic Research Society. Full text links |
| 190. | Identification of risk factors for neurological deficits in patients with pelvic fracturesOrthopedics. 2010 Aug 11;33(8). doi: 10.3928/01477447-20100625-13. AuthorsHagen Schmal 1 , Oliver Hauschild, Ulf Culemann, Tim Pohlemann, Fabian Stuby, Gert Krischak, Norbert P Südkamp Affiliation
AbstractThis multicenter register study was performed to define injury and fracture constellations that are at risk to develop pelvic associated neural lesions. Data of 3607 patients treated from 2004 to 2009 for pelvic fractures were evaluated for neurological deficits depending on Tile classification, pelvic injury configuration, and treatment.In 223 patients (6.5%), neurological lesions were diagnosed on the day of discharge from the hospital. The degree of instability of the pelvic fracture correlated with occurrence of nerve lesions. Rate of neurological dysfunction increased from 1.5% in type A fractures to 14.4% in type C fractures (P<.001). As the most endangered anatomical regions in pelvic fractures, the roots L5 (18.3%) and S1 (15.6%) and isolated peripheral nerves (19.2%) were identified. Patients sustaining complex pelvic trauma (7.85%) suffered from significantly more neurological dysfunctions (33.5%) compared to patients without peripelvic organ or soft tissue injuries (P<.001). Whereas stable type A3 sacral fractures were not associated with a different risk to develop neurological deficits (3.8%), unstable sacral fractures with the need for operative fixation showed an increased rate of accompanying nerve lesions (15.4%; P<.001). Twenty-one (11.5%) operative sacral stabilizations were supplemented with nerve root decompression (mainly S1). Neurological complications in the course of treatment were seen in 69 cases (1.9%).A high degree of instability, complex pelvic trauma, and unstable sacral fractures predispose for additional neurological deficits in patients with pelvic fractures. Copyright 2010, SLACK Incorporated. Full text links |
| 191. | Reoxygenation attenuates the adhesion of neutrophils to microvascular endothelial cellsAngiology. 2011 Feb;62(2):155-62. doi: 10.1177/0003319710375943. Epub 2010 Aug 5. AuthorsKatrin Schmitz 1 , Martina Jennewein, Tim Pohlemann, Andreas Seekamp, Martin Oberringer Affiliation
AbstractIn humans, the pathophysiological inflammation response subsequent to hypoxia and reoxygenation often leads to systemic inflammation and multiorgan failure. We applied a newly developed static interaction model using human polymorphonuclear neutrophils and microvascular endothelial cells to clarify the role of hypoxia and hypoxia/reoxygenation in vitro. Human dermal microvascular endothelial cell cultures (n = 7) were exposed to hypoxia and different reoxygenation periods and the adherence rate of neutrophils to the endothelial cells as well as to the protein matrix on the culture slide surface were determined by quantitative microscopy. Hypoxia clearly triggered neutrophil adhesion to human dermal microvascular endothelial cells whereas additional reoxygenation significantly decreased neutrophil adhesion. These in vitro findings suggest that systemic inflammation caused by increased neutrophil adherence to the microvascular endothelium is already initiated by hypoxia rather than by subsequent reoxygenation. Full text links |
| 192. | Changes in the treatment of acetabular fractures over 15 years: Analysis of 1266 cases treated by the German Pelvic Multicentre Study Group (DAO/DGU)Injury. 2010 Aug;41(8):839-51. doi: 10.1016/j.injury.2010.04.010. Epub 2010 May 6. AuthorsBjörn Gunnar Ochs 1 , Ivan Marintschev, Heike Hoyer, Bernd Rolauffs, Ulf Culemann, Tim Pohlemann, Fabian Maria Stuby Affiliation
AbstractEpidemiological, clinical and radiological data of 1266 patients with a unilateral acetabular fracture of up to 29 hospitals was reviewed. Three time periods, 1991-1993 (Registry I; n=359), 1998-2000 (Registry II; n=503), and 2005-2006 (Registry III; n=404) were compared with regard to injury pattern and severity, fracture type, and chosen nonoperative vs. operative treatment to elucidate changes over time in the treatment of acetabular fractures. In the operatively treated group, time to operation, surgical approach, fracture fixation implants and fracture reduction quality were examined. 641 (50.6%) patients with isolated acetabular fractures, 410 (32.4%) multiple injured and 215 (17.0%) polytrauma patients with 642 (50.7%) simple and 624 (49.3%) associated acetabular fractures were evaluated. In the time period from 1991 to 2006, the rate of operative treatments increased nationwide to 77% (rho<0.001). The distribution of fracture types involving the anterior and posterior wall changed with age (rho<0.001). Across all registries, 583 (68.0%) operations were performed within 7 days, 212 (24.7%) operations between 7 and 14 days and 54 (6.3%) operations were performed later than 14 days after injury. An anatomical reduction (0-1mm displacement) was achieved in 551 (64%) acetabular fractures. The obtained reduction quality did not correlate with time to operation, was lower in associated than in simple fracture types, and also lower in patients with isolated acetabular fractures than in polytrauma patients. Most importantly, the fracture reduction quality did not improve over time despite a higher frequency of surgical interventions. The Kocher-Langenbeck approach was preferred in the nineties in nearly three quarters of all operative procedures. Currently, the Kocher-Langenbeck and the ilioinguinal approaches are used equally often. The fracture fixation did not change over time and is achieved in 51% with plates in combination with single screws. This multisurgeon series illustrates a nationwide performance in acetabular fracture management. Despite changes in the chosen approaches and an increased surgical frequency, the operative treatment of acetabular fractures of the last 15 years did not lead to an increased reduction quality. Therefore, the rarity and complexity of acetabular fractures demands further specific teaching by experienced acetabular surgeons, scientific research and clinical outcome evaluation. Copyright 2010 Elsevier Ltd. All rights reserved. Full text links |
| 193. | Deficiencies of folate and vitamin B12 do not affect fracture healing in miceBone. 2010 Jul;47(1):151-5. doi: 10.1016/j.bone.2010.04.592. Epub 2010 Apr 14. AuthorsJ H Holstein 1 , M Herrmann, J Schmalenbach, R Obeid, I Olkü, M Klein, P Garcia, T Histing, T Pohlemann, M D Menger, W Herrmann, L Claes Affiliation
AbstractPurpose: Recently, hyperhomocysteinemia has been shown to be associated with impaired fracture healing in mice. The main causes for hyperhomocysteinemia are deficiencies of folate and vitamin B12. However, there is no information on whether deficiencies of these B vitamins are affecting bone repair, too. Methods: We used two groups of mice to investigate the impact of folate and vitamin B12 deficiency on fracture healing: mice of the first group were fed a folate- and vitamin B12-deficient diet (n=14), while mice of the second group received an equicaloric control diet (n=13). Four weeks after stabilizing a closed femur fracture, bone repair was analyzed by histomorphometry and biomechanical testing. In addition, serum concentrations of homocysteine, folate, vitamin B12, the bone formation marker osteocalcin (OC), and the bone resorption marker collagen I C-terminal crosslaps (CTX) were measured. Results: Serum analyses revealed significantly decreased concentrations of folate and vitamin B12 in animals fed the folate- and vitamin B12-deficient diet when compared to controls. This was associated with a moderate hyperhomocysteinemia in folate- and vitamin B12-deficient mice, while no hyperhomocysteinemia was found in controls. Three-point bending tests showed no significant differences in callus stiffness between bones of folate- and vitamin B12-deficient animals and those of control animals. In accordance, the histomorphometric analysis demonstrated a comparable size and tissue composition of the callus, and also serum markers of bone turnover did not differ significantly between the two groups. Conclusions: We conclude that folate and vitamin B12 deficiency does not affect bone repair in mice. 2010 Elsevier Inc. All rights reserved. Full text links |
| 194. | [Concept for treatment of pelvic ring injuries in elderly patients. A challenge]Unfallchirurg. 2010 Apr;113(4):258-71. doi: 10.1007/s00113-010-1762-3. [Article in German] AuthorsU Culemann 1 , A Scola, G Tosounidis, T Pohlemann, F Gebhard Affiliation
AbstractWhereas pelvic injuries in patients in their 20s and 30s are typically caused by high energy trauma, another group suffering this injury are elderly patients between the seventh and eighth decades of life. Due to osteoporosis and co-morbidities females are particularly affected by low energy trauma. After examining the medical history a physical examination of the pelvis is performed. This is followed by imaging with X-ray and CT scanning with 3D reconstruction if necessary. If there are concomitant injuries additional diagnostics are essential (e.g. sonography, MRI, retrograde ureterography, cystography and excretion urogram). The standard AO/ATO classification (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association) has been well proven and does not depend on the age of the patient. Three different fracture types are differentiated, types A, B and C. This classification in combination with the description of the affected anatomical region (e.g. transsymphysis, transpubic, etc.) is sufficient in the daily clinical practice to decide on the necessary treatment. Often there are diagnostic difficulties in elderly patients (so-called differentiation of the A-B problem). In these patients a type A fracture is initially diagnosed and treated conservatively but due to persistent pain the imaging is repeated and an additional (insufficiency) fracture is found. With this new information the therapeutic regime has to be changed. The reconstruction of the pelvic ring is of major importance especially for elderly patients. This reduces the pain and the primary objective, an earliest possible rehabilitation without prolonged immobilization, can be achieved. In elderly patients external fixation with supra-acetabular screw positioning is an effective procedure and secondary insufficiency-instability (mostly dorsal) can be avoided. Whereas type A fractures can almost exclusively be treated non-surgically, types B and C fractures usually need surgery. As in young patients type B fractures are stabilized ventrally and C fractures dorsoventrally. In an emergency supra-acetabular external fixation and when required extraperitoneal tamponade has been established as the standard treatment for elderly patients in Germany. For the definitive surgical management standard procedures are used, but they often have to be modified depending on the bone structure. Full text links |
| 195. | The LockingMouseNail--a new implant for standardized stable osteosynthesis in miceJ Surg Res. 2011 Aug;169(2):220-6. doi: 10.1016/j.jss.2009.11.713. Epub 2009 Dec 10. AuthorsPatric Garcia 1 , Simon Herwerth, Romano Matthys, Joerg H Holstein, Tina Histing, Michael D Menger, Tim Pohlemann Affiliation
AbstractBackground: Mouse models are of increasing interest to study cellular and molecular mechanisms during fracture healing. However, unlike in large animals and in humans, stable fixation of fractures has been difficult due to the small size of the mouse. Methods: Based on μCT-scans of a mouse femur, we developed a new intramedullary implant system comparable to a human locking nail. We analyzed fracture healing with osteotomy gap sizes of 0.00, 0.25, and 2.00 mm, which were stabilized with the LockingMouseNail. Results: Femora with a gap size of 0.00 mm and 0.25 mm showed complete fracture healing after 5 wk. Femora showed a secondary bone healing pattern with induction of a small periosteal callus. In contrast, femora with a gap size of 2.00 mm showed sparse periosteal callus formation and a lack of bone bridging even after 10 wk, indicating atrophic non-union. Conclusion: The LockingMouseNail allows standardized fixation of mouse femur fractures and also stabilization of segmental defects. By introducing different gap sizes, the healing process can be influenced, ranging from normal fracture healing to atrophic non-union formation. Therefore, the model may ideally be suited to study molecular mechanisms of normal fracture healing, delayed healing, and non-union formation. It may additionally allow studying biological properties and effectiveness of different bone substitutes in stabilized segmental defects. Copyright © 2011 Elsevier Inc. All rights reserved. Full text links |
| 196. | Hyperhomocysteinemia is not associated with reduced bone quality in humans with hip osteoarthritisClin Chem Lab Med. 2010 Jun;48(6):821-7. doi: 10.1515/CCLM.2010.155. AuthorsJoerg H Holstein 1 , Markus Herrmann, Christina Splett, Wolfgang Herrmann, Patric Garcia, Tina Histing, Moritz Klein, Karsten Kurz, Thomas Siebel, Tim Pohlemann, Michael D Menger Affiliation
AbstractBackground: Recent clinical and animal studies suggest that increased serum homocysteine (HCY) concentrations may be a risk factor for osteoporosis. In vitro studies showed that increasing HCY concentrations stimulate the activity of human osteoclasts. However, there is no data demonstrating that circulating HCY is related to structural and biomechanical properties of human bones. This study investigated the relationship between morphological as well as biomechanical bone properties and HCY serum concentrations in humans suffering from hip osteoarthritis (OA). Methods: Fasting blood samples and femoral heads were obtained from 94 males and females who underwent hip arthroplasty due to OA. Bones were assessed by dual energy X-ray absorptiometry (DXA), biomechanical testing (indentation method), and histomorphometry. Blood was collected for measurement of HCY, folate, vitamin B6, and vitamin B12. Subjects were classified as hyperhomocysteinemic (>12 micromol/L, n=47) and normohomocysteinemic (<12 micromol/L, n=47) according to their serum HCY concentrations. Results: Folate and vitamin B6, but not vitamin B12, were significantly lower in hyperhomocysteinemic subjects compared with controls. However, DXA, biomechanical testing, and histomorphometry did not reveal significant differences in bone quality between hyperhomocysteinemic subjects and controls. Conclusions: The results of the present study do not indicate a significant relationship between circulating HCY concentrations and morphological or biomechanical bone properties in humans with OA of the hip. Full text links |
| 197. | [Complex pelvic trauma in elderly patients]Unfallchirurg. 2010 Apr;113(4):281-6. doi: 10.1007/s00113-010-1764-1. [Article in German] AuthorsG Tosounidis 1 , U Culemann, D Stengel, P Garcia, R Kurowski, J H Holstein, T Pohlemann Affiliation
AbstractThe definition of complex pelvic trauma has allowed a selection of those pelvic fracture patients with the highest mortality rate. The term complex pelvic trauma is used as a definition for pelvic fractures which are associated with serious soft tissue lesions in the pelvic region. These may include visceral and neurovascular, as well as extensive skin and muscle injuries. Haemodynamic instability particularly related to vascular injuries raises the mortality dramatically. Traumatic hemipelvectomy, which represents the worst case of a complex pelvic trauma, is associated with mortality rates of up to 60%. The pelvic study groups 1-3 of the German trauma association (DGU) and the Association for Osteosynthesis (AO) provide the worldwide largest database on pelvic injuries (group 1, 1991-1993: 1,722 patients from 10 hospitals; group 2, 1998-2002: 2,569 patients from 22 hospitals; and group 3, 2005-2007: 2,704 patients from 23 hospitals). Using this database this article reviews epidemiological data, therapy concepts, associated injuries as well as the incidence and mortality rates related to complex pelvic trauma over a 16-year time period. Special attention has been paid to complex trauma in the elderly (patients >60 years of age). An additional aim of this article is to analyze the correlation between different treatment modalities and the mortality rate of complex pelvic trauma and to investigate whether changes in the treatment of complex pelvic trauma have improved the outcome of these injuries. Taken together an increase in measures for an initial mechanical stabilization of the pelvic ring, such as the use of the pelvic C clamp, the external fixator or primary osteosynthesis was found over the 16-year observation period. In addition to stabilization of the pelvic ring, pelvic tamponade for mechanical haemostasis has been proven to be one of the most effective measures to control haemorrhaging. These treatment regimes did not differ between young patients and patients >60 years of age. Regarding the outcome of these treatment strategies only slight decreases in the mortality rate were found (pelvic study group 1: 21%; pelvic study group 2: 22%; pelvic study group 3: 18%). In all pelvic study groups the mortality rate in patients >60 years of age was found to be significantly higher than in individuals <60 years of age (pelvic study group 1: 57% versus 29.6%, pelvic study group 2: 33% versus 22.6%, pelvic study group 3: 41% versus 10.4%, p <0.05, respectively). Full text links |
| 198. | Inhibition of angiotensin-converting enzyme stimulates fracture healing and periosteal callus formation - role of a local renin-angiotensin systemBr J Pharmacol. 2010 Apr;159(8):1672-80. doi: 10.1111/j.1476-5381.2010.00651.x. Epub 2010 Mar 5. AuthorsP Garcia 1 , S Schwenzer, J E Slotta, C Scheuer, A E Tami, J H Holstein, T Histing, M Burkhardt, T Pohlemann, M D Menger Affiliation
AbstractBackground and purpose: The renin-angiotensin system (RAS) regulates blood pressure and electrolyte homeostasis. In addition, 'local' tissue-specific RAS have been identified, regulating regeneration, cell growth, apoptosis, inflammation and angiogenesis. Although components of the RAS are expressed in osteoblasts and osteoclasts, a local RAS in bone has not yet been described and there is no information on whether the RAS is involved in fracture healing. Therefore, we studied the expression and function of the key RAS component, angiotensin-converting enzyme (ACE), during fracture healing. Experimental approach: In a murine femur fracture model, animals were treated with the ACE inhibitor perindopril or vehicle only. Fracture healing was analysed after 2, 5 and 10 weeks using X-ray, micro-CT, histomorphometry, immunohistochemistry, Western blotting and biomechanical testing. Key results: ACE was expressed in osteoblasts and hypertrophic chondrocytes in the periosteal callus during fracture healing, accompanied by expression of the angiotensin type-1 and type-2 receptors. Perindopril treatment reduced blood pressure and bone mineral density in unfractured femora. However, it improved periosteal callus formation, bone bridging of the fracture gap and torsional stiffness. ACE inhibition did not affect cell proliferation, but reduced apoptotic cell death. After 10 week treatment, a smaller callus diameter and bone volume after perindopril treatment indicated an advanced stage of bone remodelling. Conclusions: Our study provides evidence for a local RAS in bone that influenced the process of fracture healing. We show for the first time that inhibition of ACE is capable of accelerating bone healing and remodelling. Full text links |
| 199. | [Post-traumatic torticollis in a schoolchild: fracture, congenital anomaly or age-appropriate radiological findings of the atlas?]Unfallchirurg. 2010 Mar;113(3):230-4. doi: 10.1007/s00113-009-1696-9. [Article in German] AuthorsM Burkhardt 1 , P Garcia, P Fries, J Heinzmann, T Pohlemann, A Pizanis Affiliation
AbstractWe describe the case of a 6-year-old girl with post-traumatic torticollis after falling on her head. The suspected fractures of the dens axis and/or atlas were ruled out after performing CT and MRI examinations as well as dynamic fluoroscopy. Radiological findings showed no further instability but there was a congenital non-fusion of the posterior arch and an age-appropriate non-fused anterior arch of the atlas. In addition to discoligamental injuries and fractures, congenital anomalies and normal variants of the immature anatomy of the cervical spine should also be considered in the diagnosis of the pediatric cervical spine after trauma. Full text links |
| 200. | Different stabilisation techniques for typical acetabular fractures in the elderly--a biomechanical assessmentInjury. 2010 Apr;41(4):405-10. doi: 10.1016/j.injury.2009.12.001. Epub 2009 Dec 24. AuthorsU Culemann 1 , J H Holstein, D Köhler, C C Tzioupis, A Pizanis, G Tosounidis, M Burkhardt, T Pohlemann Affiliation
AbstractObjectives: The tremendous increase of acetabular fractures in the elderly provides new challenges for their surgical treatment. The aim of this study was to evaluate the biomechanical properties of conventional and newly developed implants for the stabilisation of an anterior column combined with posterior hemitransverse fracture (ACPHTF), which represents the typical acetabular fracture in the elderly. Methods: Using a single-leg stance model we analysed four different implant systems for the stabilisation of ACPHTFs in synthetic and cadaveric pelvises. Applying an increasing axial load, fracture dislocation was analysed with a new multidirectional ultrasonic measuring system. Results of the different implant systems were compared by Scheffé post hoc test and one-way ANOVA. Results: In synthetic pelvises, the standard reconstruction plate fixed by 3 periarticular long screws and a new titanium fixator with multidirectional interlocking screws were associated with significantly less dislocation of the fractured quadrilateral plate of the acetabulum when compared to a standard reconstruction plate fixed by only one periarticular long screw and a locking reconstruction plate. No significant differences between the different osteosynthesis techniques could be observed in cadaver pelvises, probably due to a heterogeneous bone quality. Conclusions: We conclude that the plate fixation by positioning of periarticular long screws as well as the multidirectional positioning of interlocking screws account for the most sufficient fracture stabilisation of ACPHTFs under experimental conditions. Copyright (c) 2009 Elsevier Ltd. All rights reserved. Full text links |