Resident autonomy in orthopedic trauma: independent femoral IMN by senior residents yields comparable outcomes to fellowship-trained surgeons.

INTRODUCTION: Intramedullary nailing (IMN) of femoral shaft fractures is a fundamental cornerstone procedure in orthopedic trauma and an important benchmark of resident surgical competency. While independent resident operating is essential for skill development, its safety in complex trauma cases remains debated. This study evaluated whether senior residents can safely perform femoral IMN without direct supervision compared with fellowship-trained trauma surgeons. MATERIALS AND METHODS: A retrospective cohort analysis was performed of adult patients undergoing IMN for isolated femoral shaft fractures between 2015 and 2023 at a level I trauma center. Cases were grouped by primary surgeon: senior residents (postgraduate year ≥ 4) versus attending trauma surgeons. Demographics, fracture characteristics, operative parameters, complications, and revision rates were compared. To minimize selection bias, 1:1 propensity score matching (PSM) was performed based on preoperative covariates including age, comorbidity, fracture type, injury mechanism, and severity. RESULTS: A total of 207 patients met inclusion criteria; 150 (75 per group) were matched. Operative duration was longer in resident-led cases (median 120 vs. 91 min, p = 0.003). Postoperative hospital stay (5.0 vs. 6.0 days, p = 0.674) and weight-bearing protocols (p = 0.218) were similar. Overall complication rates did not differ significantly (12.0% residents vs. 20.0% attendings, p = 0.265), nor did revision rates (20.0% vs. 18.7%, p = 0.841). CONCLUSION: When appropriately trained and selected, orthopedic residents can independently perform femoral shaft IMN with clinical outcomes comparable to fellowship-trained trauma surgeons. Structured autonomy programs emphasizing competency-based progression allow residents to achieve operative independence in complex trauma procedures without compromising patient safety. LEVEL OF EVIDENCE: Level III - a retrospective cohort design.