Biomechanical Comparison of Fixation Methods for Posterior Wall Fractures of the Acetabulum: Conventional Reconstruction Plate vs. Spring Plate vs. Variable Angle Locking Compression Plate.

Background and Objectives: Acetabular fractures, though infrequent, present considerable challenges in treatment due to their association with high-energy trauma and poor prognoses. Posterior wall fractures, the most common type among them, typically have a more favorable prognosis compared to other types. Anatomical reduction and stable fixation of the posterior wall are crucial for optimal treatment outcomes. This study aimed to biomechanically compare three commonly used fixation methods for posterior wall fractures of the acetabulum-a conventional reconstruction plate, a spring plate, and a 2.7 mm variable angle locking compression plate (VA-LCP). Materials and Methods: The study utilized 6 fresh-frozen cadavers, yielding 12 hemipelvises free from prior trauma or surgery. Three fixation methods were compared using a simple acetabulum posterior wall fracture model. Fixation was performed by an orthopedic specialist, with prebending of plates to minimize errors. Hemipelvises were subjected to quasi-static and cyclic loading tests, measuring fracture gap, stiffness, and displacement under load. Results: It showed no significant differences in fracture gap among the three fixation methods under cyclic loading conditions simulating walking. However, the conventional reconstruction plate exhibited a greater stiffness compared to the spring and variable angle plates. Fatigue analysis revealed no significant differences among the plates, indicating a similar stability throughout cyclic loading. Despite differences in stiffness, all three fixation methods demonstrated adequate stability under loading conditions. Conclusions: While the conventional reconstruction plate demonstrated a superior stiffness, all three fixation methods provided sufficient stability under cyclic loading conditions similar to walking. This suggests that postoperative limitations are unlikely with any of the three methods, provided excessive activities are avoided. Furthermore, the variable angle plate-like the spring plate-offers an appropriate stability for fragment-specific fixation, supporting its use in surgical applications. These findings contribute to understanding the biomechanical performance of different fixation methods for acetabular fractures, facilitating improved surgical outcomes in challenging cases.

Comparative Short-Term Outcomes of Femoral Neck System (FNS) and Cannulated Screw Fixation in Patients with Femoral Neck Fractures: A Multicenter Study.

Background: Femoral neck fractures need to be treated in their early stages with accurate reduction and stable fixation to reduce complications. The authors compared the early radiologic outcomes of femoral neck fractures treated with the recently introduced Femoral Neck System (FNS, Depuy-Synthes) with conventional cannulated screws (CS) in a multicenter design. Furthermore, the factors associated with early failure after FNS were analyzed. Methods: The FNS group included 40 patients treated between June 2019 and January 2020, and the CS group included 65 patients treated between January 2015 and May 2019. The operation was performed in 3 university hospitals. Patient demographics, fracture classification, postoperative reduction quality, sliding distance of FNS or CS, union and time to union, and complication rates were examined. Logistic regression analysis was performed on candidate factors for early failure of the FNS group. Results: The FNS group had a 90% union rate and a mean time to union of 4.4 months, while the CS group had similar results with an 83.1% union rate and a mean time to union of 5.1 months. In the subgroup analysis of Pauwels type III fractures, the union rates were 75.0% and 58.8% in the FNS and CS groups, respectively, and the time to union was significantly shorter in the FNS group with 4.8 months compared to 6.8 months in the CS group. Early failure rate within 6 months of FNS fixation was observed to be 10%, which included 3 reduction failures and 1 excessive sliding with a broken implant. Risk factors for early failure after FNS were identified as displaced fractures (Garden classification type III or IV), poor reduction quality, longer tip-apex distance, greater sliding distance, and 1-hole implants, of which sliding distance was the only significant risk factor in multivariate analysis. Conclusions: In femoral neck fractures, FNS and CS did not show significant differences for short-term radiologic results. FNS resulted in shorter operative time than cannulated screw fixation and favorable outcomes in Pauwels type III femoral neck fractures. The FNS could be considered a reliable and safe alternative to CS when treating femoral neck fractures.

Percutaneous bridge plating of extra-articular distal fibular fracture for the management of distal tibia type III open fracture.

PURPOSE: The aim of this study is to conduct clinical and radiographic evaluations of the use of percutaneous bridge plating for distal fibular fractures combined with distal tibia type III open fractures. METHODS: Thirty-four patients with acute distal third fibular shaft fractures (4F2A(c) and 4F2B(c) according to the AO/OTA classification) combined with distal tibia type III open fractures were enrolled. Concurrent fibular fractures were fixed with the percutaneous bridge plating simultaneously, while distal tibia open fractures were temporally stabilized with a spanning external fixator. Clinical and radiographic outcomes were evaluated using the Lower Extremity Functional Scale (LEFS), the proportional length difference of the fibula, the talocrural angle, the union rate of the fibula and tibia, the operation time, and complications at the final follow-up. RESULTS: All fibular fractures healed with an average bone healing time of 20.7 ± 6.3 weeks (range, 16-35). The mean proportional length difference was 0.492 ± 0.732% compared with that in the uninjured fibula. The functional assessment result according to the LEFS was 74.0 ± 3.70 points (range, 57-80). No cases of fibula fracture infection developed throughout the follow-up period in any of the patients. Iatrogenic postoperative superficial peroneal nerve injury was not found in any of the patients. CONCLUSION: With the perspective of minimizing soft tissue problems due to high-energy trauma, the application of percutaneous bridge plating for the treatment of distal fibular fractures can be an alternative to conventional treatment methods.

Improvement of outcomes in patients with pelvic fractures and hemodynamic instability after the establishment of a Korean regional trauma center.

PURPOSE: Despite using a multidisciplinary treatment approach, the mortality rate of patients with hemodynamic instability from severe pelvic fractures is still 40-60%. We evaluated the improvement of outcomes in this patient population after the establishment of a regional trauma center in Korea. METHODS: We retrospectively reviewed the medical charts of 50 patients with hemodynamic instability due to pelvic fractures between March 2011 and November 2016. Patients were divided into two groups: the pre-trauma center (PTC) group (n = 23) and trauma center (TC) group (n = 27). RESULTS: Sixteen (32.0%) patients died of exsanguination. Patients in the TC group had shorter trauma resuscitation room stay (101 vs 273 min, p < 0.001) and underwent preperitoneal pelvic packing (PPP) more frequently (88.9 vs 8.7%, p < 0.001) than those in the PTC group. During the TC period, emergent procedures such as PPP and pelvic angiography were performed more frequently (92.6 vs 39.1%, p < 0.001). Although there was no statistical difference in the overall mortality rate between groups, patients in the TC group had less mortality due to hemorrhage (18.5 vs 47.8%, p = 0.027). Logistic regression analysis demonstrated that initial systolic blood pressure and establishment of trauma center were independent protective factors of mortality from hemorrhage [odds ratio (OR) 0.957, 95% confidence interval (CI) 0.926-0.988, p = 0.007; OR 0.134, 95% CI 0.028-0.633, p = 0.011]. CONCLUSIONS: Since the regional trauma center was established, emergent procedures such as pelvic angiography and PPP were performed more frequently, and mortality due to exsanguination was significantly decreased.

Evaluation of three-dimensional in vivo scapular kinematics and scapulohumeral rhythm between shoulders with a clavicle hook plate and contralateral healthy shoulders.

PURPOSE: Acromioclavicular-coracoclavicular ligament injury occurs frequently, and the clavicle hook plate technique is an easy-to-use treatment method. However, complications such as subacromial impingement syndrome, synovitis, erosion, osteolysis, post-operative pain, and post-operative limitations in range of motion have been reported. We aimed to evaluate the use of the clavicle hook plate in the shoulder joints and to compare in vivo three-dimensional (3D) scapular kinematics and scapulohumeral rhythm between the shoulders with a clavicle hook plate and contralateral normal shoulder joints. METHODS: Ten male patients (aged 40.5 ± 14.4 years) who underwent clavicle hook plate fixation for an acromioclavicular-coracoclavicular ligament injury were selected. Computed tomography and fluoroscopy were conducted on both the shoulder joints, and 3D models were created. Using a 3D-2D model-image registration technique, we determined the 3D coordinates of the scapula, and we measured the scapular kinematics and scapulohumeral rhythm. RESULTS: The values for upward rotation, posterior tilt, and external rotation in the two groups increased in proportion with humeral elevation, showing significant differences between the two groups (p < 0.05). Overall, the value in the clavicle hook plate group (group H) was smaller than that in the control group (group C) by 23.5% (6.7°) of upward rotation and 64.8% (18.9°) of posterior tilt. However, the external rotation in group H was greater than that in group C by 32.3% (2.3°). In overall value, there was a significant difference not in upward rotation and external rotation, but in posterior tilt. During humeral elevation, the overall changes in scapulohumeral rhythm were 4.65 ± 2.45 in group H and 3.8 ± 0.8 in group C, and statistical differences were not detected between the two groups. CONCLUSIONS: Clavicle hook plate fixation changes the scapular kinematics and scapulohumeral rhythm; thus, when clavicle hook plate fixation is complete, the implant should be promptly removed.

Effectiveness and postoperative wound infection of preperitoneal pelvic packing in patients with hemodynamic instability caused by pelvic fracture.

INTRODUCTION: Despite the use of a multidisciplinary treatment approach, the mortality rate of hemodynamic instability due to severe pelvic fracture remains 40-60%. Several recent studies have shown that preperitoneal pelvic packing (PPP) was useful for achieving hemostasis in these patients in the acute phase. However, few studies have examined postoperative complications. The purpose of the present study was to evaluate clinical outcomes and wound infections of PPP in these patients. MATERIALS AND METHODS: We retrospectively reviewed the medical charts of 62 patients with hemorrhagic shock due to pelvic fracture between March 2011 and May 2017. Excluding four patients (two with other major hemorrhage sites and two who experienced cardiac arrest in the emergency room), the patients were divided into PPP (n = 30) and non-PPP (n = 28) groups according to PPP application. Clinical outcomes including early-stage mortality, transfusion amount, and surgical site infection (SSI) were compared between the two groups. RESULTS: The overall mortality rate was 48.3% and the mean Injury Severity Score (ISS) was 39 ± 9. The 30 patients in the PPP group had a significantly lower hemorrhage-induced mortality rate than the 28 patients in the non-PPP group (16.7% vs 50%, p = 0.019), although both groups had similar patient characteristics (age, ISS, and initial serum lactate level). Independent factors associated with hemorrhage-induced mortality were PPP and the requirement of packed red blood cells for 4 h. In the PPP group, SSI occurred in 5 of 25 (20%) patients. CONCLUSIONS: PPP may be considered as a hemostatic modality for hemodynamic instability due to pelvic fracture because it reduces the hemorrhage-induced mortality rate. However, wound infections after the procedure should be considered.

Chronic Irreducible Anterior Dislocation of the Shoulder without Significant Functional Deficit.

Shoulder dislocation is frequently encountered by orthopedists, and closed manipulation is often sufficient to treat the injury in an acute setting. Although most dislocations are diagnosed and managed promptly, there are rare cases that are missed or neglected, leading to a chronically dislocated state of the joint. They are usually irreducible and cause considerable pain and functional disability in most affected patients, prompting the need to find a surgical method to reverse the worsening conditions caused by the dislocated joint. However, there are cases of even greater rarity in which chronic shoulder dislocations are asymptomatic with minimal functional or structural degeneration in the joint. These patients are usually left untreated, and most show good tolerance to their condition without developing disabling symptoms or significant functional loss over time. We report on one such patient who had a chronic shoulder dislocation for more than 2 years without receiving treatment.

Effect of glenohumeral position on contact pressure between the capsulolabral complex and the glenoid in free ALPSA and Bankart lesions.

PURPOSE: Anterior shoulder dislocation is a common injury, but the optimal management of dislocation remains controversial. We hypothesized that reducing the shoulder in externally rotated position would aid the reduction in capsulolabral lesions. Thus, in this study, contact pressure between the capsulolabral lesion and the glenoid in free ALPSA and Bankart lesions was measured using a cadaver model. METHODS: In 10 specimens, the humerus was externally rotated by abduction on the coronal plane to measure the contact pressure between the capsulolabral complex and glenoid in free ALPSA and Bankart lesions using a Tekscan pressure system. Stability of the joint was confirmed using the Vicon motion analysis system. RESULTS: In the normal shoulder joint, the peak pressure between the subscapularis muscle and the anterior capsule according to the location of the glenohumeral joint decreased to 83.4 ± 21.2 kPa in the 0° abduction and -30° external rotation positions and showed a 300.7 ± 42.9 kPa peak value in the 60° abduction and 60° external rotation positions. In both free ALPSA and Bankart lesions, the lowest pressure between the labral lesion and the glenoid was measured at 0° abduction and -30° external rotation, and the highest pressure was recorded at 60° external rotation and 60° abduction. CONCLUSION: The contact pressure between the capsulolabral complex and the glenoid significantly increased when the abduction and external rotation angles were increased. Based on our results, the conservative management in free ALPSA lesions would respond better than Bankart lesions. IRB OR ETHICAL COMMITTEE APPROVAL: YWMR-12-0-038.