Three-Dimensional Heat Map: The OTA/AO Type 43C Pilon Fracture Lines Distribution.

Background: This study aimed to create three-dimensional heat map and study the characteristic of fracture lines and represented fragments of OTA/AO type 43C pilon fractures. Methods: CT scan was performed in105 fractures diagnosed with OTA/AO type 43C pilon fractures between January 2017 and December 2022. Three-dimensional pilon fracture maps were created and converted into fracture heat maps. CT scan graphic parameters including the fracture line height, α angle, ß angle, the ratio of the area and size of bone fragment represented by the fracture line to the total articular surface were measured. Results: The study included 105 patients with 91 males and 14 females. The fractures included C1 (n=16), C2 (n=23), and C3 (n=66). There was no statistically different among the most parameters except in the fracture-line height of the anterior fracture line (p=0.03) and the sagittal fracture line (p=0.02) between C2 and C3 pilon fractures. The average size of the anterolateral fragment, occupied approximately 13.5% of the articular surface area, was (11.5±2.8) mm × (20.5±6.3) mm with the average height of 29.8 mm. The average size of the posterolateral fragment, occupied approximately 13.0% of the articular surface area, was (15.7±4.6) mm × (19.3±4.0) mm with the average height of 19.1 mm. Conclusion: This study demonstrates that the articular surface fracture lines in the C type pilon fracture are formed by fixed main fracture lines. The understand of morphological and distribution characteristics of the fracture lines and size of fragments in OTA/AO type 43C pilon fractures would help the surgeons take suitable approach and fixation.

Comparative Analysis of Eccentric Glenosphere in Reverse Total Shoulder Arthroplasty: A Computer Simulation Study.

Objective: The aim was to evaluate the effects of different glenosphere eccentricities on impingement, range of motion (ROM), and muscle length during standard activities in reverse total shoulder arthroplasty (RSA). Methods: In this study, we utilized computational modeling techniques to create native shoulder and shoulder models undergoing RSA and simulate shoulder movements in all abduction-adduction, flexion-extension, and rotation. We tested a total of 36 different glenosphere configurations, which included three different inferior tilts (0°, +10°, +20°) and two different lateral offsets (0 mm and +4 mm), as well as six different glenosphere eccentricities (concentricity, inferior, posterior, anterior, anteroinferior, and posteroinferior). We evaluated the maximum impingement-free ROM, impingement sites, and muscle lengths. Results: All glenosphere configurations exceeded 50% of native shoulder ROM in three planes and total global ROM. In abduction-adduction, there was no significant difference among the different glenosphere eccentricities (p > 0.05). In flexion-extension, the posteroinferior eccentricity had the maximum ROM among the different eccentricities, but no significant difference among the different glenosphere eccentricities (p > 0.05). In rotation, there was a significant difference overall, and anteroinferior eccentricity had a significant advantage over concentricity (p < 0.05). In total global ROM, anteroinferior eccentricity had a significant advantage over concentricity when lateral offset was 0 mm (p < 0.05). In all models of glenosphere eccentricities, only the elongation of the infraspinatus muscle was statistically significant (p < 0.05). Conclusion: Glenosphere eccentricity significantly influenced rotation, total global ROM, and the length of the subscapularis muscle. Among them, anteroinferior offset achieved the maximum ROM in abduction-adduction, rotation, and total global activities. Both anteroinferior and inferior glenoid eccentricity showed significant advantages over the concentricity in rotation and total global ROM. Level of Evidence: Basic Science Study; Computer Modeling.

Intrawound application of vancomycin reduces the proportion of fracture-related infections in high-risk tibial plateau fractures.

INTRODUCTION: Despite the improvements in surgical techniques and the use of prophylactic intravenous antibiotics, the fracture-related infection (FRI) incidence after high-risk tibial plateau fractures remains high. This study aimed to evaluate the clinical effect of the intrawound application of vancomycin on the FRI after high-risk tibial plateau fracture surgery. METHODS: A total of 243 patients who underwent high-risk tibial plateau fracture surgery from May 2013 to June 2021 were retrospectively reviewed. Of these, 233 cases were enrolled. Considering the preoperative patient condition, surgeons applied vancomycin powder directly into the surgical site before wound closure in 105 cases (intrawound application of vancomycin powder with preoperative intravenous cephalosporin). The remaining 128 cases served as the control group (preoperative intravenous cephalosporin alone). Clinical data and surgical details were recorded. The Cox proportional hazards regression analysis was used to assess risk factors for FRI. The Kaplan-Meier method and the log rank test illustrated the infection status of patients based on the application of intrawound vancomycin. The primary outcome was an FRI within one year. Secondary outcomes included bacterial culture and vancomycin-related complications. RESULTS: Our study demonstrated a significant difference in the incidence of FRI between the vancomycin group and the control group (3.8% versus 10.9%; p=0.041). Multivariable Cox regression showed the intrawound application of vancomycin powder decreased the rate of FRI. There were no complications related to intrawound vancomycin observed during follow-up. The presence of Gram-positive FRI was higher in the control group compared with the vancomycin group. CONCLUSIONS: Intrawound application of vancomycin was associated with a significant lower rate of FRI after high-risk tibial plateau fracture surgery compared to the control group.

Predictive Indicators for Complications of Proximal Humerus Fractures Treated with Locking Plate or Intramedullary Nail Fixation.

OBJECTIVE: The purpose of this study was to evaluate the best placement of calcar screws in proximal humerus fracture surgeries. METHODS: This retrospective cohort study included clinical and radiographic outcomes of 98 patients treated with proximal humerus fracture surgeries between January 2017 and June 2020. Demographic data of patients were obtained from medical records. The surgical and radiographic results were also collected: operation time, blood loss, time to surgery, fibular allograft, disruption of medial region hinge, Neer classification, and recovery of medial support. Patients were allocated into two groups: the locking plate group (n = 65) and the intramedullary nail group (n = 33). In this study, we proposed new predictive indicators, named horizontal ratio (HR) and vertical ratio (VR), to quantify the placement of calcar screws in these two groups. A receiver operating characteristic (ROC) analysis was conducted to display the accuracy of these indicators. Shoulder activity, visual scale analog (VAS) score, and Constant score were performed to evaluate postoperative clinical outcomes at 1 year follow-up. RESULTS: In the multivariate logistic regression analysis, only time to surgery and effective medial support were considered statistically significant factors of postoperative complications (p < 0.05). Significant differences were observed between medial support and postoperative complications both in the locking plate group and the intramedullary nail group (p < 0.05). Only the vertical ratio of locking plate (VRLP) was a statistically significant predictor of postoperative complications (p < 0.05). The area under curve was calculated to assess the predictive value of VRLP, which came to 0.84. In addition, a ROC analysis found quantifiable thresholds of the VR was 0.1713 as measures to avoid postoperative complications in the locking plate fixation. CONCLUSION: In locking plate fixation, the incidence of postoperative complications increased significantly when the VR of calcar screws greater than 0.1713, which was beneficial to surgeons to place calcar screws.

Intra- and inter-observer reliability assessment of widely used classifications and the "Ten-segment classification" of tibial plateau fractures.

BACKGROUND: Ten-segment classification provides a different approach to the evaluation of tibial plateau fractures. The purpose of this study was to assess the intra- and inter-observer reliability of three widely used classification systems (Schatzker, Arbeitsgemeinschaft für Osteosynthesefragen (AO/OTA), and the updated three-column concept (uTCC)) with ten-segment classification in two-dimensional computed tomography (2D-CT) and three-dimensional computed tomography (3D-CT). METHOD: Ninety 2D-CT and 3D-CT scans of patients with tibial plateau fractures were included in this retrospective cohort study. The included data were independently classified by six observers of different years of seniority and were independently observed and classified again after eight weeks. Inter-observer and intra-observer reliability of the four fracture classifications made by the six observers was analyzed using the kappa statistic. Kappa values were interpreted according to the categorical rating by Landis and Koch. RESULTS: When the inter-observer reliability was based on 2D-CT/3D-CT analysis, the mean Kappa values for the Schatzker, AO/OTA, uTCC, and ten-segment classification were 0.64/0.66, 0.56/0.59, 0.53/0.65, and 0.60/0.73, respectively. When intra-observer reliability was based on 2D-CT/3D-CT, the mean Kappa values for the Schatzker, AO/OTA, uTCC, and ten-segment classification were 0.68/0.83, 0.69/0.83, 0.74/0.85, and 0.80/0.91, respectively. CONCLUSIONS: The use of 3D-CT is important for the reliable diagnosis and recognition of tibial plateau fracture features compared to 2D-CT. When using 3D-CT, ten-segment classification showed high intra- and inter-observer agreement.