Functional And Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study

Background: Fractures of the distal third femoral shaft present a major orthopedic challenge due to their anatomical proximity to the knee joint and the complex biomechanical stresses acting on this region. These fractures often result from high-energy trauma and are associated with complications such as malunion, nonunion, and knee stiffness. The distal femoral intramedullary locking nail (DFN) has gained popularity as a minimally invasive fixation method offering improved stability, reduced soft-tissue trauma, and early mobilization. Aim: To evaluate the surgical and functional outcomes of distal third femoral shaft fractures treated with distal femoral intramedullary locking nail (DFN). Materials and Methods: This prospective observational study was conducted on 38 patients aged 20–80 years with distal one-third femoral shaft fractures at MGM Medical College & LSK Hospital, Kishanganj, Bihar, over 18 months. Patients were treated with DFN fixation and followed up for 12 months. Union rate, time to union, malunion, nonunion, infection rate, and functional recovery were assessed using the Knee Society Score (KSS) and Lower Extremity Functional Scale (LEFS). Statistical analysis was performed using SPSS v26 with significance set at p < 0.05. Results: The majority of patients were males (73.7%) aged 30–49 years, with road traffic accidents accounting for 73.7% of injuries. Mean operative time was 92.6 ± 15.4 minutes and mean blood loss 210 ± 40 ml. Radiological union was achieved in 94.7% of patients, with most fractures uniting within six months. Overall union rate was 78.9%, while delayed union, malunion, and nonunion occurred in 10.5%, 5.3%, and 5.3% of cases respectively. Mean KSS was 86.1 ± 7.2 and mean LEFS 70.4 ± 8.3, indicating satisfactory functional recovery in 78.9% of patients. Conclusion: DFN is a reliable, effective, and minimally invasive fixation method for distal third femoral shaft fractures, providing high union rates, early rehabilitation, and good functional outcomes with minimal complications