Femoral Neck System Fixation in Young Adults: A Prospective Cohort Analysis of Functional and Radiological Outcomes

Background: Femoral neck fractures in young adults pose a significant challenge due to high shear forces and the need for head-preserving fixation. Conventional methods are associated with complications such as non-union and avascular necrosis. The Femoral Neck System (FNS) has been developed to provide improved biomechanical stability and minimally invasive fixation. Material and Methods: This prospective single-centre cohort study included 15 adults (20 to 60 years) with acute femoral neck fractures treated with FNS between March 2023 and March 2025. Patients underwent standardized surgical fixation and postoperative rehabilitation. Functional outcomes were assessed using the Harris Hip Score (HHS), while radiological union was evaluated through serial radiographs and CT imaging up to 18 months. Statistical analysis was performed using SPSS, with significance set at p<0.05. Results: The mean age was 37.6 ± 9.1 years, with road traffic accidents being the most common mechanism (60%). Radiological union was achieved in 86.7% of patients at a mean of 14.1 ± 6.2 weeks. Mean HHS improved significantly from 68.3 at 6 weeks to 87.7 at 18 months (p<0.001), with 80% achieving excellent or good outcomes. No significant associations were found between outcomes and demographic or fracture variables, though earlier surgery showed a trend toward better results. Conclusion: FNS provides reliable fixation with favourable functional and radiological outcomes in young adults with femoral neck fractures, including unstable patterns. It represents an effective head-preserving strategy; however, larger comparative studies with longer follow-up are needed to confirm its long-term superiority.

Keywords: Femoral Neck System (FNS); Femoral Neck Fracture; Internal Fixation; Harris Hip Score (HHS); Pauwels Classification; Young Adults.