Purpose Negative buttress reduction should be avoided in the treatment of femoral neck fractures (FNFs) using conventional fixation. As the femoral neck system (FNS) has been recently developed and utilized widely to treat FNFs, the association of reduction quality with postoperative complications and clinical function has not been clarified. The purpose of this study was to evaluate the clinical effect of nonanatomical reduction in young patients with FNFs treated with FNS. Methods This multicenter, retrospective cohort study included 58 patients with FNFs treated with FNS between September 2019 and December 2021. According to the reduction quality immediately following surgery, patients were classified into positive, anatomical, and negative buttress reduction groups. Postoperative complications were assessed with 12 months of follow-up. The logistic regression model was used to identify risk factors for postoperative complications. The postoperative hip function was assessed using the Harris hip scores (HHS) system. Results At a follow-up of 12 months, a total of eight patients (8/58, 13.8%) had postoperative complications in three groups. Compared with the anatomical reduction group, negative buttress reduction was significantly associated with a higher complication rate (OR = 2.99, 95%CI 1.10–8.10, P = 0.03). No significant associations were found between positive buttress reduction and the incidence of postoperative complications (OR = 1.21, 95%CI 0.35–4.14, P = 0.76). The difference was not statistically significant in Harris hip scores. Conclusion Negative buttress reduction should be avoided in young patients with FNFs treated with FNS.

Background : The aim of the present study was to introduce a novel three-dimensional computed tomography (3DCT)-based three-column classification (named “MLP classification system”) of intertrochanteric fracture, and evaluate its reproducibility and reliability. Methods : From September 2020 to September 2022, a total of 258 consecutive patients (60 male, 198 female; mean age 81.3 years) with intertrochanteric fracture were included in this study. The fracture in each case was assessed using a novel three-dimension computed tomography-based three-column classification. Two examiners tested the intra and inter-observer reliability of this new classification system using kappa variance. Results : Intertrochanteric region was divided into medial column, lateral column and posterior column. Intertrochanteric fractures were documented as M0/1/2L0/1/2/3P0/1/2/3. All fractures were classifiable into the new classification system. The intra and inter-observer kappa value were 0.91 and 0.82 respectively, indicating almost perfect reliability. Conclusion : This novel 3DCT-based MLP classification system for intertrochanteric fractures is comprehensive, reproducible with good agreement. It is based on proximal femur biomechanic characteristics and traumatic mechanism, contributing to formulate more reasonable treatment protocols involving various late-model internal fixation systems.

Purpose Negative buttress reduction should be avoided in the treatment of femoral neck fractures (FNFs) using conventional implant devices. As the femoral neck system (FNS) has been recently developed and utilized widely to treat FNFs, the clinical efficacy of reduction quality has not been clarified. The purpose of this study was to evaluate clinical effects of nonanatomical reduction in young FNFs treated with FNS. Methods This multicenter, retrospective cohort study included 58 patients diagnosed as FNFs between September 2019 and December 2021. According to radiographs immediate following surgery, reduction quality were classified into positive, anatomical and negative buttress reduction groups. Assessment of postoperative hip function using Harris hip scores (HHS) system and postoperative complication rate was performed. Logistic regression model was used to analyses risk factors. Results Postoperative complication rate and Harris hip scores showed no significant difference in groups (P ＞0.05). Adjusted smoking status [OR = 1.991, 95%CI (1.063, 3.698)], Pauwels classification [OR = 2.012, 95%CI (1.216, 4.325)] were independent risk factors for postoperative complications. Compared with anatomical reduction, negative buttress reduction [OR = 2.987, 95%CI (1.101, 6.337)] was found to be significantly associated with complications after surgery in femoral neck fractures treated with FNS. Conclusion Negative buttress reduction should be constantly avoided in young FNFs treated with FNS or conventional implant devices.