[National challenges for trauma surgery in Germany due to violence and war]. / Nationale Herausforderungen für die Unfallchirurgie in Deutschland bei Gewalt und Krieg.

Due 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.

Experimental and virtual testing of bone-implant systems equipped with the AO Fracture Monitor with regard to interfragmentary movement.

Introduction: 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.

Improved weight bearing during gait at 6 weeks post-surgery with an angle stable locking system after distal tibial fracture.

BACKGROUND: 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.

Experiences in the Use of Motorized Intramedullary Nails after Complex Injuries to the Extremities. / Erfahrungen bei der Anwendung motorisierter Marknägel nach komplexen Extremitätenverletzungen.

The 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.

Sacroiliac Screw Placement with Ease: CT-Guided Pelvic Fracture Osteosynthesis in the Elderly.

Background 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.

Concepts and clinical aspects of active implants for the treatment of bone fractures.

Nonunion 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.

How effective are different models of pelvic binders: results of a study using a Pelvic Emergency Simulator.

BACKGROUND: 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.

[Case-based learning can improve the teaching quality in trauma surgery education : A survey analysis among medical students]. / Fallbasiertes Lernen kann die Lehrqualität im unfallchirurgischen Unterricht verbessern : Eine Umfrageanalyse unter Medizinstudierenden.

BACKGROUND: 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.

Macrophage-activating lipoprotein (MALP)-2 impairs the healing of partial tendon injuries in mice.

Tendon 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.

Individualized Determination of the Mechanical Fracture Environment After Tibial Exchange Nailing-A Simulation-Based Feasibility Study.

Non-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.

Long-term results of reconstructing the joints' articular surface in the knee and ankle with the surgical diamond instrumentation (SDI).

PURPOSE: 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.

Vascularization Strategies in the Prevention of Nonunion Formation.

Delayed 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.

A novel press-fit minimally-invasive symphysiodesis technique.

OBJECTIVE: 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.

Flexor tendon grafts for pulley reconstruction - Morphological aspects.

BACKGROUND: 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.

A novel internal fixation method for open book injuries of the pubic symphysis- A biomechanical analysis.

BACKGROUND: 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.

Stabilization of a Type B1.1 Injury in a Morbidly Obese Patient Using an Internal Fixator in a Minimally Invasive Technique: A Case Report.

CASE: 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.

Autologous Transplantation of Press-fit Bone Cylinders in the Treatment of Pelvic Nonunion.

The 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.

VEGF-loaded mineral-coated microparticles improve bone repair and are associated with increased expression of epo and RUNX-2 in murine non-unions.

A 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.

Cement augmentation of the proximal humerus internal locking system in elderly patients: a multicenter randomized controlled trial.

INTRODUCTION: 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.

Geriatric Acetabular Surgery: Letournel's Contraindications Then and Now-Data From the German Pelvic Registry.

OBJECTIVE: 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.