Computer Navigation-assisted Bilateral Total Knee Arthroplasty with Osteosynthesis in Single Sitting in Patients Presenting with Distal Femur Fracture with Pre-existing Knee Arthritis: A Case Series.

Background: Intra-articular and periarticular distal femur fractures with pre-existing osteoporosis (OP) and osteoarthritis (OA) pose a significant challenge to ambulatory patients because of the higher chances of implant failure and severe disability of OA. To reduce OA-related morbidity, we advocate simultaneous total knee arthroplasty (TKA) with fracture fixation instead of fracture fixation alone using computer-assisted navigation to achieve proper ligament balance, restoration of the mechanical axis, and component alignment. Case Report: A case series of four patients (male - 2 and females - 2) with periarticular fractures of the distal femur with severe OA and OP were primarily fixed with different modalities such as distal femur locking plates, cannulated-cancellous screw, and Herbert screw followed by computer navigation-assisted cruciate retaining TKA. All patients had Kellgren Lawrence grade ≥3 OA and underwent bilateral TKA. All patients were aggressively treated for OP using pulsed PTH therapy. Patients were found to have a faster recovery with the initiation of early partial weight bearing with crutches postoperatively in all patients, followed by unassisted weight bearing once radiological union was seen. Conclusion: Based on satisfactory quality evidence and navigation-assisted cruciate-retaining TKA appears to be a useful treatment option for distal femoral fractures with pre-existing OA and OP. This is cost-effective and is associated with the least morbidity and excellent patient satisfaction.

Analysis of postoperative complications 5 years after osteosynthesis of patella fractures-a retrospective, multicenter cohort study.

PURPOSE: The study aims to investigate the influence of patient- and fracture-specific factors on the occurrence of complications after osteosynthesis of patella fractures and to compare knee joint function, activity, and subjective pain levels after a regular postoperative course and after complications in the medium term. METHODS: This retrospective, multicenter cohort study examined patients who received surgery for patella fracture at level 1 trauma centers between 2013 and 2018. Patient demographics and fracture-specific variables were evaluated. Final follow-up assessments included patient-reported pain scores (NRS), subjective activity and knee function scores (Tegner Activity Scale, Lysholm score, IKDC score), complications, and revisions. RESULTS: A total of 243 patients with a mean follow-up of 63.4 ± 21.3 months were included. Among them, 66.9% of patients underwent tension band wiring (TBW), 19.0% received locking plate osteosynthesis (LPO), and 14.1% underwent screw osteosynthesis (SO). A total of 38 patients (15.6%) experienced complications (TBW: 16.7%; LPO: 15.2%; SO: 11.8%). Implant-related complications of atraumatic fragment dislocation and material insufficiency/dislocation, accounted for 50% of all complications, were significantly more common after TBW than LPO (p = 0.015). No patient-specific factor was identified as a general cause for increased complications. Overall, particularly following complications such as limited range of motion or traumatic refracture, functional knee scores were significantly lower and pain levels were significantly higher at the final follow-up when a complication occurred. Implant-related complications, however, achieved functional scores comparable to a regular postoperative course without complications after revision surgery. CONCLUSION: The present study demonstrated that implant-related complications occurred significantly more often after TBW compared to LPO. The complication rates were similar in all groups.

Stable fixation using absorbable sutures in craniofacial surgery in patients over 24 months of age-a retrospective study.

PURPOSE: In craniofacial surgery, the stable fixation of transposed bone segments is crucial in order to ensure good long-term results. The use of absorbable material in fixation avoids the need for a second surgery, which would otherwise be required to remove osteosynthesis material. The authors of the present manuscript have already demonstrated that absorbable sutures ensure the stable fixation of bone segments in patients up to 24 months of age. However, it has thus far remained unclear whether stable fixation is possible in older patients by using only absorbable sutures due to the slower bone remodelling and prolonged healing time in this cohort. METHOD: For the present study, osteosynthesis was performed in 50 patients ranging from 25.7 to 192.1 months of age (mean, 61.4 ± 21.7 months) using solely absorbable sutures (PDS II®, Ethicon, Germany). Post-operative stability and possible restrictions-such as foreign body reactions-were evaluated within clinical and radiological routine follow-ups. RESULTS: All children demonstrated clinically and radiologically stable osteosynthesis both directly post-operatively and in follow-ups. No significant foreign body reaction could be seen. CONCLUSION: The present study demonstrates-for the first time-that absorbable sutures with a longer absorption period are also very well suited for the fixation of bone segments in patients over 24 months of age. The sole use of absorbable sutures in children over 24 months of age is a safe procedure with nearly no foreign body reactions. The procedure enables stable and highly cost-effective osteosynthesis without altering the osteotomy design.

Patient-specific implants made of 3D printed bioresorbable polymers at the point-of-care: material, technology, and scope of surgical application.

BACKGROUND: Bioresorbable patient-specific additive-manufactured bone grafts, meshes, and plates are emerging as a promising alternative that can overcome the challenges associated with conventional off-the-shelf implants. The fabrication of patient-specific implants (PSIs) directly at the point-of-care (POC), such as hospitals, clinics, and surgical centers, allows for more flexible, faster, and more efficient processes, reducing the need for outsourcing to external manufacturers. We want to emphasize the potential advantages of producing bioresorbable polymer implants for cranio-maxillofacial surgery at the POC by highlighting its surgical applications, benefits, and limitations. METHODS: This study describes the workflow of designing and fabricating degradable polymeric PSIs using three-dimensional (3D) printing technology. The cortical bone was segmented from the patient's computed tomography data using Materialise Mimics software, and the PSIs were designed created using Geomagic Freeform and nTopology software. The implants were finally printed via Arburg Plastic Freeforming (APF) of medical-grade poly (L-lactide-co-D, L-lactide) with 30% ß-tricalcium phosphate and evaluated for fit. RESULTS: 3D printed implants using APF technology showed surfaces with highly uniform and well-connected droplets with minimal gap formation between the printed paths. For the plates and meshes, a wall thickness down to 0.8 mm could be achieved. In this study, we successfully printed plates for osteosynthesis, implants for orbital floor fractures, meshes for alveolar bone regeneration, and bone scaffolds with interconnected channels. CONCLUSIONS: This study shows the feasibility of using 3D printing to create degradable polymeric PSIs seamlessly integrated into virtual surgical planning workflows. Implementing POC 3D printing of biodegradable PSI can potentially improve therapeutic outcomes, but regulatory compliance must be addressed.

Long stem revision versus short stem revision with plate osteosynthesis for Vancouver type B2 periprosthetic femoral fracture: a comparative study of eighty five cases.

PURPOSE: Periprosthetic femoral fractures (PPFs) around the hip are challenging complications in orthopaedic surgery, particularly Vancouver type B2 (VTB2) fractures. The surgical management of these fractures is crucial and depends on various factors. Cementless short taper stem with plate osteosynthesis is an alternative surgical technique. This study aims to compare the outcomes of this surgical technique with revision arthroplasty (RA) with long stem in the treatment of VTB2 PPFs. METHODS: This retrospective study was conducted in a single medical institute from February 2010 to May 2019. Patients who had received either total hip arthroplasty or bipolar hemiarthroplasty and subsequently developed a VTB2 PPF were included; patients who sustained intra-operative fractures or received a cemented stem previously were excluded from the analysis. The patients were divided into two groups: group I received RA with cementless long stem, while group II underwent RA with cementless short taper stem with plate osteosynthesis. Demographic data, radiographic and functional outcomes, and complications were analyzed between the two groups. RESULTS: A total of 85 patients diagnosed with VTB2 PPFs were included in the study. There were no significant differences between the two groups in terms of demographic data, including age, gender, mean follow-up times, estimated blood loss, and operative times. The radiographic results showed that there was no significant difference in the incidence of subsidence and implant stability between the two groups. However, group II tended to have less subsidence and periprosthetic osteolysis. Patients in group II had significantly better functional scores (mean Harris hip score: post-operative: 60.2 in group I and 66.7 in group ii; last follow-up: 77.4 in group 1 and 83.2 in group II (both p < 0.05)). There were no significant differences in the overall complication rate, including infection, dislocation, re-fracture, and revision surgery, between the two groups. CONCLUSIONS: Both surgical techniques, cementless long stem and cementless short taper stem with plate osteosynthesis, are effective in the treatment of Vancouver B2 PPFs, with no significant differences in outcomes or complications. However, patients in cementless short taper stem with plate osteosynthesis had better functional scores at both post-operative and the last follow-up.

Use of metatarsal hook plates in the treatment of multifragmentary patellar fractures - A case series.

The surgical management of patellar fractures typically yielded satisfactory results; however, in situations involving multifragmented patellar fractures or those affecting the inferior pole, it became imperative to employ alternative osteosynthesis techniques that enhanced stability, enabled early rehabilitation initiation, prevented implant failure, and avoided reduction loss before fracture consolidation. In this context, an unconventional osteosynthesis alternative was presented, utilizing an anatomically designed hook plate originally intended for the fifth metatarsal. This technique was successfully applied in three patients with multifragmentary patellar fractures, allowing stable fixation of small or marginal fragments through the plate's hooks without compromising vascularity. Fracture consolidation was achieved without reduction loss, and owing to its low profile, patient discomfort and irritation were minimized compared to traditional tension band or wiring techniques. This approach suggested the potential to forego early plate removal, thereby contributing to a more effective management of patellar fractures. Level of evidence: IV.

Inflammatory tissue response in human soft tissue is caused by a higher particle load near carbon fiber-reinforced PEEK compared to titanium plates.

Titanium as the leading implant material in locked plating is challenged by polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK), which became the focus of interest of researchers and manufacturers in recent years. However, data on human tissue response to these new implant materials are rare. Osteosynthesis plates and peri-implant soft tissue samples of 16 healed proximal humerus fractures were examined (n = 8 CFR-PEEK, n = 8 titanium). Soft tissue was analyzed by immunohistochemistry and µCT. The entrapped foreign bodies were further examined for their material composition by FTIR. To gain insight into their origin and formation mechanism, explanted and new plates were evaluated by SEM, EDX, profilometry and HR-CT. In the peri-implant soft tissue of the CFR-PEEK plates, an inflammatory tissue reaction was detected. Tissues contained foreign bodies, which could be identified as tantalum wires, carbon fiber fragments and PEEK particles. Titanium particles were also found in the peri-implant soft tissue of the titanium plates but showed a less intense surrounding tissue inflammation in immunohistochemistry. The surface of explanted CFR-PEEK plates was rougher and showed exposed and broken carbon fibers as well as protruding and deformed tantalum wires, especially in used screw holes, whereas scratches were identified on the titanium plate surfaces. Particles were present in the peri-implant soft tissue neighboring both implant materials and could be clearly assigned to the plate material. Particles from both plate materials caused detectable tissue inflammation, with more inflammatory cells found in soft tissue over CFR-PEEK plates than over titanium plates. Statement of Significance: Osteosynthesis plates are ubiquitously used in various medical specialties for the reconstruction of bone fractures and defects and are therefore indispensable for trauma surgeons, ENT specialists and many others. The leading implant material are metals such as titanium, but recently implants made of polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK) have become increasingly popular. However, little is known about human tissue reaction and particle generation related to these new implant types. To clarify this question, 16 osteosynthesis plates (n=8 titanium and n=8 CFR-PEEK) and the overlying soft tissue were analyzed regarding particle occurrence and tissue inflammation. Tissue inflammation is clinically relevant for the development of scar tissue, which is discussed to cause movement restrictions and thus contributes significantly to patient outcome.

Comparison of femoral neck shortening after femoral neck system and cannulated cancellous screw fixation for displaced femoral neck fractures in young adults.

BACKGROUND: The purpose of this study was to compare the outcomes of femoral neck shortening between the femoral neck system (FNS) and the cannulated cancellous screws (CCS) for displaced femoral neck fractures in young adults PATIENTS AND METHODS: In this retrospective analysis, 225 patients aged 18-65 years with displaced femoral neck fracture were divided into two groups according to internal fixation: 135 patients in the FNS group and 90 patients in the CCS group. The length of hospital stay, duration of surgery, intraoperative blood loss, quality of reduction, extent of femoral neck shortening, incidence of femoral neck shortening, femoral neck shortening at each follow-up visit, Harris hip score (HHS), reoperation, and complications were compared between the two groups. RESULTS: The median follow-up time was 28.2 (26.0, 31.2) months in the FNS group and 30.2 (26.3, 34.7) months in the CCS group. The follow-up time, age, sex distribution, body mass index (BMI), mechanism of injury, injured side, length of hospital stay, time from injury to surgery, and fracture classification were similar between the groups. Duration of surgery was longer in the FNS group (65.0 (55.0, 87.0) min versus 55.0 (50.0, 65.0) min, P<0.001); intraoperative blood loss was greater in the FNS group (50.0 (20.0, 60.0) ml versus 20.0 (10.0, 35.0) ml, P<0.001). Femoral neck shortening was 2.4 (1.0, 4.5) mm in the FNS group versus 0.6 (0.0, 2.6) mm in the CCS group at 1 month postoperatively (P<0.001); 3.7 (1.8, 6.4) mm in the FNS group versus 1.2 (0.6, 3.8) mm in the CCS group at 3 months (P<0.001); 4.1(2.4, 7.7) mm in the FNS group versus 2.3 (1.1, 4.4) mm in the CCS group at 6 months (P<0.001); 4.2 (2.6, 7.7) mm in the FNS group versus 2.6 (1.3, 4.6) mm in the CCS group at 12 months (P<0.001); and 4.5 (2.8, 8.0) mm in the FNS group versus 2.8 (1.5, 4.8) mm in the CCS group at 18 months (P<0.001). The two groups showed no significant differences in HHS, reoperation, and reduction quality. CONCLUSION: Compared to CCS, FNS is deficient in preventing femoral neck shortening. Future research should focus on improving FNS in terms of preventing femoral neck shortening.

Novel implant design for comminuted posterior wall acetabular fractures.

BACKGROUND: In recent years, the medical community has witnessed a notable increase in high-energy traumatic injuries, leading to a surge in complex fracture patterns that challenge existing treatment methodologies. Among these, the posterior approach to acetabular fractures stands out for offering direct visualization of the retro-acetabular surface, with current fixation methods relying on 3.5 mm low-profile reconstruction plates and various other implants. Despite the effectiveness of these methods, there is a burgeoning demand for a singular, adaptable implant that not only streamlines the surgical process but also optimizes patient outcomes. METHODS: In an innovative approach to address this need, three-dimensional (3D) models of the posterior acetabular wall were meticulously crafted using AutoCAD® software. The chosen material for the implant was 316L surgical steel for its durability and strength. The design of the implant featured a low-profile mesh structure, which was instrumental in facilitating osteosynthesis. This design allowed for the placement of screws of varying lengths in multiple directions, ensuring the initial reconstruction of the joint in an anatomical position without hindering the placement of the definitive implant. The primary objective was to secure the fixation and stabilization of the fracture by specifically targeting the smaller bone fragments. A comparative analysis was then conducted between this novel plate and a conventional 316L surgical steel, seven-hole, 3.5 mm reconstruction plate through finite element analysis. RESULTS: The comparative analysis unveiled that both plates demonstrated comparable deformation capacities, with no significant differences in load-bearing capabilities observed. This finding suggests that the innovative plate can match the performance of traditional plates used in such surgeries. CONCLUSIONS: The finite element analysis revealed that the newly developed anatomical plate for posterior wall acetabular fractures meets the necessary physical and mechanical criteria for permanent implementation in patients with these fractures. This breakthrough represents a promising advancement that could simplify surgical procedures and potentially elevate patient outcomes. LEVEL OF EVIDENCE II: This study is classified as a Level II, diagnostic study.

SVF Therapy of Delayed Fracture Union in Patients with Multiple Combat Injury. Case Report.

Delayed union of fractures is one of the most frequent complications in orthopedic practice, especially in polytrauma patients. With the development of new methods of regenerative medicine, including the use of adipose derived stromal cells as a component of the stromal-vascular fraction (SVF), new possibilities for conservative treatment of this problem have emerged. This article presents a clinical case of conservative treatment of delayed union of a radial bone fracture using local SVF injections. In the fracture space, SVF with PRP creates a pool of cells that could differentiate towards surrounding tissue, releases various inducers of tissue growth and, via an indirect chemotactic effect on receptors, mobilizes the body's own resources and creates conditions for angiogenesis and trophism in the injured segment. In the patient with delayed consolidation after SFV-therapy, progress in clinical and radiological dynamics was noted with complete healing within 7 months. The positive clinical result provides a basis for further study and implementation in practice.

Critical loss of primary implant stability in osteosynthesis locking screws under cyclic overloading.

Primary implant stability, which refers to the stability of the implant during the initial healing period is a crucial factor in determining the long-term success of the implant and lays the foundation for secondary implant stability achieved through osseointegration. Factors affecting primary stability include implant design, surgical technique, and patient-specific factors like bone quality and morphology. In vivo, the cyclic nature of anatomical loading puts osteosynthesis locking screws under dynamic loads, which can lead to the formation of micro cracks and defects that slowly degrade the mechanical connection between the bone and screw, thus compromising the initial stability and secondary stability of the implant. Monotonic quasi-static loading used for testing the holding capacity of implanted screws is not well suited to capture this behavior since it cannot capture the progressive deterioration of peri­implant bone at small displacements. In order to address this issue, this study aims to determine a critical point of loss of primary implant stability in osteosynthesis locking screws under cyclic overloading by investigating the evolution of damage, dissipated energy, and permanent deformation. A custom-made test setup was used to test implanted 2.5 mm locking screws under cyclic overloading test. For each loading cycle, maximum forces and displacement were recorded as well as initial and final cycle displacements and used to calculate damage and energy dissipation evolution. The results of this study demonstrate that for axial, shear, and mixed loading significant damage and energy dissipation can be observed at approximately 20 % of the failure force. Additionally, at this load level, permanent deformations on the screw-bone interface were found to be in the range of 50 to 150 mm which promotes osseointegration and secondary implant stability. This research can assist surgeons in making informed preoperative decisions by providing a better understanding of the critical point of loss of primary implant stability, thus improving the long-term success of the implant and overall patient satisfaction.

Non-unions and wound infections do not differ following intramedullary nailing and plate osteosynthesis for distal third femur fractures: a meta-analysis.

Purpose: The fixation method of distal, extra-articular femur fractures is a controversially discussed. To ensure better stability itself, earlier mobilization and to prevent blood loss - all these are justifications for addressing the femur via reamed intramedullary nailing (RIMN). Anatomical reposition of multifragmentary fractures followed by increased risks of non-union are compelling reasons against it. The purpose of this study was to systematically review the literature for rates of non-union and wound infection, as well as blood loss and time of surgery. Methods: According to the PRISMA guidelines we conducted this systematic review by searching the Cochrane, PubMed, Ovid, MedLine, and Embase databases. Inclusion criteria were the modified Coleman methodology score (mCMS) >60, age >18 years, and extra-articular fractures of the distal femur. Biomechanical and animal studies were excluded. By referring to title and abstract relevant articles were reviewed independently. In the consecutive meta-analysis, we compared 9 studies and 639 patients. Results: There is no statistically significant difference comparing superficial wound infections when RIMN was performed (OR = 0.50; 95% CI: 0.18 - 1.42; P = 0.19) as well as in deep wound infections (OR = 0.74; 95% CI: 0.19-2.81; P = 0.62). However, these results were not significant. We also calculated for potential differences in the rate of non-unions depending on the surgical treatment applied. Data of 556 patients revealed an overall number of 43 non-unions. There was no significant difference in rate of non-unions between both groups (OR = 0.97; 95% CI: 0.51-1.85; P = 0.92). Conclusion: No statistical difference was found in our study among RIMN and plate fixation in the treatment of distal femoral fractures with regard to the incidence of non-union and wound infections. Therefore, the indication for RIMN or plating should be made individually and based on the surgeon's experience.

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.

Newly designed plate for the treatment of posterolateral tibial plateau fractures: a finite element analysis.

BACKGROUND: This study investigated the biomechanical properties of a new plate used for the treatment of posterolateral tibial plateau fractures using finite element analysis. METHODS: The study groups were as follows: group PM, model of the new plate with posteromedial tibial plateau fracture; group PL, model of the new plate with posterolateral tibial plateau fracture; and group PC, model of the new plate with posterior tibial plateau fracture. We used two loading modes: uniform loading on the entire plateau, and loading on the posterior plateau. Data such as the displacement of the fracture and distribution of stress on the new plate and screws were recorded and analyzed. RESULTS: When the whole plateau was loaded, the displacement of fractures in groups PM, PL, and PC were 0.273, 0.114, and 0.265 mm, respectively. The maximum stresses on the plates in groups PM, PL, and PC were 118.131 MPa, 44.191 MPa, and 115.433 MPa. The maximum stresses on the screws in Groups PM, PL, and PC were 166.731, 80.330, and 164.439 MPa, respectively. When the posterior tibial plateau was loaded, the displacement of the fractures in groups PM, PL, and PC was 0.410, 0.213, and 0.390 mm, respectively. The maximum stresses on the plates in groups PM, PL, and PC were 194.012 MPa, 72.806 MPa, and 185.535 MPa. The maximum stresses on the screws in Groups PM, PL, and PC were 278.265, 114.839, and 266.396 MPa, respectively. CONCLUSION: The results of this study revealed that titanium plates have good fixation effects in all groups; therefore, the use of the new plate for posterolateral tibial plateau fractures appears to be safe and valid.

Intramedullary Nailing of Humeral Shaft Fractures: Percutaneous Nailing in the lateral position through the Neviaser approach is a reliable Technique.

BACKGROUND: Displaced humeral shaft fractures are frequently treated by osteosynthesis in the active patient. We aimed to evaluate the results of intra-medullary nailing (IMN) in the lateral position with the Neviaser approach and to compare them with those from IMN nailing in the standard position and conventional approach. METHODS: In the retrospectively evaluated, single-center study, we compared 20 cases of long IMN for fractures of the proximal or middle third of the humerus shaft (Multilock; Synthes Laboratory) in the lateral position with the percutaneous Neviaser approach with 52 cases of IMN in the standard position. The mean age of patients was 62+/-21 years. Clinical outcomes were analyzed: Constant score, subjective shoulder evaluation (SSV) score and range of motion (ROM). Radiographically, entry point at the proximal part of the humerus, the healing rate and the possible association between the critical shoulder angle (CSA) and the correct positioning of the nail were assessed. RESULTS: With a mean follow-up of 26+/-2 months, the healing rate was 89% (64/72) in the overall series, (8 patients in non-union), with no difference between the 2 groups. The overall mean active anterior elevation (AAE) was 125+/-22 degrees, mean external rotation (ER1) was 35+/-17 degrees, and mean internal rotation (IR) was at L3. The mean Constant score was 58+/-23 and SSV score 73+/-12%. ROMs were better in the lateral than standard position group (AAE 133+/-17 vs 122+/-23, p=0.03; ER1 47+/-13 vs 30+/-16, p<0.001; IR T12 vs L5, p=0.02). The nail was less often protruding in the lateral than standard position group (1/20 [5%] vs 20/52 [38.5%], p=0.002). The nail was better positioned from the anteroposterior view (nail centered: 16/20 [75%] vs 26/52 [50%], p=0.047) and lateral view (nail centered: 18/20 [90%] vs 34/52 [65.4%], p=0.02) in the lateral than standard position group. We found no association between nail position, type of approach and CSA. CONCLUSIONS: In the short-term follow-up, osteosynthesis of humeral shaft fractures by using long IMN in the lateral position with the Neviaser approach is a reliable technique. The positioning of the nail, in particular its entry point, and the clinical results were better with the lateral position and Neviaser approach than with the standard position and conventional approach. Further studies with a larger number of patients, assessment of the learning curve, and analysis of the impact of this technique on comorbidities (unchanged cerebral perfusion) are needed to fully validate this technique.

Triangular osteosynthesis and lumbopelvic fixation as a valid surgical treatment in posterior pelvic ring lesions: a systematic review.

Objective: Unstable fractures of the sacrum often occur in patients with pelvic fractures and represent a real challenge for the orthopedic surgeon. Triangular osteosynthesis (TOS) and lumbopelvic fixation (LP) may represent a valid management option for the treatment of this condition. We present a systematic literature review about lumbopelvic fixation and triangular fixation as treatment option for unstable sacral fractures, to assess clinical and radiological outcomes after surgery and to evaluate appropriate indications and impact on the natural history of sacral fractures. Methods: The review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. 50 articles out of 108 titles, were considered eligible for the full-text analysis. Finally, 16 studies that met inclusion criteria were included in this review. Results: Overall, 212 patients (87 males, 58 females) with sacral fractures treated with TOS triangular fixation or LP lumbopelvic fixation were collected. The mean age was 37.6 years. Mean follow-up reported in all studies was 24.14 months. Conclusion: The results presented by the different authors, highlight the effectiveness of TOS triangular fixation and LP lumbopelvic fixation for the treatment of unstable sacral fractures associated with other pelvic fractures, in terms of function, stability, cost-effectiveness, and quality of life postoperatively.

Bilateral acetabular fractures (case report).

INTRODUCTION AND IMPORTANCE: Bilateral acetabular fractures are very rare. They are usually seen in the context of multiple trauma patients. This type of fracture poses a problem and difficulty in therapeutic management, sometimes resulting in serious sequelae and significant morbidity. CASE PRESENTATION: We report a rare case of bilateral simultaneous acetabular fracture in an adult, forty-seven years old man due to a road accident. CLINICAL DISCUSSION: Bilateral acetabular fractures are very rare. While bilateral acetabular fracture most frequently occur due to automobile accidents, other mechanism can be responsible for this injury as well. Furthermore, bilateral acetabular fractures are frequently associated with other lesions of the surrounding bones or tissues. Surgery is the most suitable treatment in most cases. The development of osteoarthritis is the most common complication of acetabular fracture and is directly related to the post-operative reduction obtained. Heterotopic ossifications are a complication associated with acetabular fracture. In acetabular fracture, the primary objective of surgical treatment is anatomical reduction of the fracture that will determinate the future of hip. CONCLUSION: The treatment goal of acetabular fracture is anatomic or near anatomic reduction of the articular surface. The risk of osteonecrosis is mostly related to the initial injury and time to reduction.

Complications and clinical outcomes with minimally invasive plate osteosynthesis (MIPO) technique for midshaft clavicle fractures: a systematic review and meta-analysis.

Background: Clavicle fractures are among the most common upper limb fractures in adults, with the midshaft region being the most frequently affected site. Minimally invasive plate osteosynthesis (MIPO) has emerged as an alternative to the traditional open reduction and internal fixation (ORIF) technique, offering potential advantages. The purpose of this study was to conduct a systematic review to explore the results of this technique in the existing literature, with emphasis on the occurrence of surgical complications and functional outcomes and also to provide a comprehensive comparison of MIPO and ORIF in the management of midshaft clavicle fractures. Methods: We conducted a systematic review to evaluate the complication incidence and clinical outcomes of MIPO for midshaft clavicle fractures. We searched PubMed/Medical Literature Analysis and Retrieval System Online (MEDLINE), Scopus, the Cochrane Database of Controlled Trials, and the Cochrane Database of Systematic Reviews databases without language or date restrictions. Studies focusing on midshaft clavicle fractures treated with MIPO were included, while other clavicle fractures and nonclinical studies were excluded. The risk of bias was assessed using the Methodological Index for Nonrandomized Studies criteria and the Risk of Bias Tool 2 Cochrane tool. Data synthesis included qualitative analysis, and if applicable, quantitative analysis and meta-analysis. Adherence to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines ensured reporting quality. Results: A total of 107 studies were initially identified, after applying inclusion and exclusion criteria, 22 studies were included for data extraction. These studies involved the evaluation of 714 clavicles treated with the MIPO technique. Of the 714 MIPO cases, 11 cases of implant failure, 5 nonunions, 2 infections, and 28 cases with neurological impairment were observed. Quantitative analysis comparing MIPO with ORIF revealed that MIPO had significantly shorter surgery time (mean difference -12.95, 95% confidence interval [-25.27 to -0.63], P = .04) and lower occurrence of numbness (odds ratio 0.29, 95% CI [0.15-0.56], P = .0002) compared to ORIF. Time to bone union, functional outcomes, and other complications were similar between MIPO and ORIF at the final follow-up. An overall moderate risk of bias was found across the studies. Conclusion: The MIPO technique yields good and comparable results to ORIF for midshaft clavicle fractures. Additionally, the MIPO technique may offer advantages such as reduced surgical time and lower chances of neurological impairment.

Development of a test bench for biomechanical simulation-a preliminary study of mandibular forces.

Purpose: The aim of this study is to develop a test bench, which integrates different complexity levels and enables in that way a flexible and dynamic testing for mid and long term intervals as well as testing of maximum loads till implant failure of different osteosynthesis systems on the mandible. Material and Methods: For this purpose, an analysis of the state of the art regarding existing test benches was combined with interviews of clinical experts to acquire a list of requirements. Based on these requirements a design for a modular test bench was developed. During the implementation of the test stand, functional tests were continuously carried out and improvements made. Depending on the level of complexity, the test bench can be used either as an incorporated variant or as a standalone solution. In order to verify the performance and the degree of fulfilment of the requirements of these two variants of the test bench, preliminary studies were carried out for all levels of complexity. In these preliminary studies, commercially available osteosynthesis and reconstruction plates were investigated for their biomechanical behaviour and compared with data from the literature. Results: In total, fourteen test runs were performed for the different levels of complexity. Firstly, five test runs were executed to test the simplified load scenario in the incorporated variant of the test bench. High forces could be transmitted without failure of the miniplates. Secondly a quasi-static test scenario was examined using the incorporated variant with simplified load insertion. Five experiments with a number of cycles between 40,896 and 100,000 cycles were carried out. In one case the quasi-static testing resulted in a fracture of the tested reconstruction plate with a failure mode similar to the clinical observations of failure. The last four test runs were carried out using the standalone variant of the test bench simulating complex load patterns via the insertion of forces through imitated muscles. During the test runs joint forces were measured and the amplitude and vector of the resulting joint forces were calculated for both temporomandibular joints. Differences in the force transmission depending on the implant system in comparison to the zero sample could be observed. Conclusion: The presented modular test bench showed to be applicable for examination of the biomechanical behavior of the mandible. It is characterized by the adjustability of the complexity regarding the load patterns and enables the subsequent integration of further sensor technologies. Follow-up studies are necessary to further qualify and optimize the test bench.

Predictive factors for infection after osteosynthesis of tibial plateau fractures: a retrospective study of 314 patients.

INTRODUCTION: The reported incidence of infection related with tibial plateau fractures (IRTPF) ranges from 2 to 23%. This complication can result in catastrophic consequences such as deformity, post-traumatic osteoarthritis, chronic pain, loss of function, and substantial economic burdens on healthcare systems due to extended hospital stays and the resources required for treatment. Consequently, it is imperative to emphasize the identification of infection risk factors. METHODS: A retrospective case-control study was designed, encompassing patients who underwent surgery for tibial plateau fractures between 2015 and 2020. Frequencies and measures of central tendency were compared between infected patients (cases) and non-infected patients (controls) using rank-based statistical tests. Subsequently, two logistic regression models were employed to control for potential confounding variables. RESULTS: A total of 314 patients were included, predominantly male (71.15%). Average age of 44.41 years. IRTPF were observed in 7.64% of the patients. In the univariate inferential statistical analysis, high-energy fractures (OR 6.35, p < 0.001), fractures with compartment syndrome (OR 7.10, p < 0.001), two-stage management with temporary external fixation (OR 8.18, p < 0.001), the use of 2 or more approaches in definitive surgery (OR 2.93, p = 0.011), and the use of two or more plates (OR 9.17, p < 0.001) were identified as risk factors for infection. On average, the duration of surgery in infected patients was 201.2 min, compared to 148.4 min in non-infected patients (p < 0.001). When performing two logistic regression models, the following independent risk factors were identified: high-energy fractures (OR 5.04, p = 0.012), the presence of compartment syndrome (OR 4.53, p = 0.007), and the use of two or more plates in definitive surgery (OR 5.04, p = 0.023). CONCLUSIONS: High-energy tibial plateau fractures (Schatzker IV, V, and VI), the presence of concomitant compartment syndrome, and the use of 2 or more plates in definitive surgery are associated with a higher risk of infection related to fracture following open reduction and osteosynthesis treatment. LEVEL OF EVIDENCE: Case-Control Study.