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

Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1245 International Journal of Medical and Pharmaceutical Research Online ISSN-2958-3683 | Print ISSN-2958-3675 Frequency: Bi-Monthly Available online on: https://ijmpr.in/ Research Article Functional And Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study Dr. Jaideep Singh 1, Dr. Biprajit Roy1, Dr. Harmanpreet Singh1 Dr. Papa Naik Haridas2 1 Post Graduate Trainee (Final Year), Department of Orthopedics, MGM Medical College & LSK Hospital, Kishanganj, Bihar. 2Professor, Department of Orthopedics, MGM Medical College & LSK Hospital, Kishanganj, Bihar. A B S T R A C T Corresponding Author: Dr. Jaideep Singh Dr. Jaideep Singh, Post Graduate Trainee (Final Year), Department of Orthopedics, MGM Medical College & LSK Hospital, Kishanganj, Bihar Received: 07-09-2025 Accepted: 25-09-2025 Available online: 08-10-2025 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 highenergy 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. Copyright © International Journal of Medical and Pharmaceutical Research Keywords: distal femur fracture, intramedullary nail, DFN, functional outcome, knee society score INTRODUCTION: Fractures involving the distal third of the femoral shaft pose a major orthopedic challenge due to their proximity to the knee joint, complex biomechanics, and risks of malunion, nonunion, and joint stiffness.[1] These injuries usually result from high-energy trauma such as road traffic accidents or falls and are often associated with polytrauma.[2] Various fixation methods, including plating, retrograde intramedullary nailing, and external fixation, have been employed, but the optimal treatment remains debated.[3] Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1246 The distal femoral intramedullary locking nail (DFN) offers a minimally invasive, load-sharing construct that preserves soft tissue and allows early mobilization.[4] It provides multiple distal locking options to enhance metaphyseal stability, accommodating the widened canal and thinner cortices of the distal femur.[5] Compared to conventional plating or dynamic condylar screw fixation, DFN minimizes soft-tissue trauma and facilitates faster rehabilitation with comparable union rates and reduced complications.[6,7] Despite its advantages, literature on DFN remains limited, with few prospective evaluations addressing functional and surgical outcomes.[8] This observational prospective study aims to analyze the results of DFN fixation in distal third femoral shaft fractures, focusing on union rate, time to union, functional recovery, and complications, thereby contributing evidence-based guidance for improved orthopedic management. Objectives: To evaluate the surgical and functional outcomes of patients with distal third femoral shaft fractures treated with distal femoral intramedullary locking nail (DFN) in terms of union rate, time to union, malunion, nonunion, infection rate, range of motion at the knee joint (using Knee Society Score and Lower Extremity Functional Scale), and procedurerelated complications. Materials and Methods Study Design: This was a prospective observational study conducted in the Department of Orthopaedics, MGM Medical College & LSK Hospital, Kishanganj, Bihar, over 18 months after approval from the Institutional Ethics Committee. Study Population: Patients aged 20–80 years presenting with distal one-third femoral shaft fractures treated with a Distal Femoral Intramedullary Locking Nail (DFN) were included. Sample Size: Based on prevalence (p = 2.5%) and 5% allowable error, the minimum sample size calculated was 38 patients. Inclusion Criteria: 1. Age 20–80 years 2. Distal third shaft fracture of femur 3. Willingness for regular follow-up Exclusion Criteria: 1. Pathological or intra-articular fractures 2. Active infection at the fracture site 3. Previous surgery on the same limb 4. Systemic illness affecting bone healing Methodology: Eligible patients were enrolled after consent. All underwent standard preoperative evaluation, closed or open reduction, and DFN fixation under C-arm guidance. Postoperatively, patients received antibiotics, early mobilization, and physiotherapy. Follow-ups were scheduled at 6 weeks, 3, 6, 9, and 12 months. Outcome Measures: • Primary: Union rate, time to union, malunion/nonunion, and infection rate • Secondary: Functional outcome (Knee Society Score, Lower Extremity Functional Scale), complications, and patient satisfaction Ethical Considerations: Ethical clearance was obtained from the Institutional Ethics Committee of MGM Medical College & Hospital. Written informed consent was obtained from all study participants prior to enrollment. Statistical Analysis: Descriptive statistics were used to summarize demographic, clinical, and outcome data. Continuous variables were presented as mean ± standard deviation or median with interquartile range, while categorical variables were expressed as frequencies and percentages. Data analysis was performed using SPSS version 26. A p-value of <0.05 was considered statistically significant. Results & Analysis: Table 1: Age Distribution of Patients (n = 38) Age Group (Years) Number of Patients Percentage (%) Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1247 20–29 5 13.2% 30–39 8 21.1% 40–49 10 26.3% 50–59 7 18.4% 60–69 5 13.2% 70–80 3 7.9% Total 38 100% In our study comprising 38 patients with distal one-third shaft fractures of the femur, the age distribution revealed that the majority of patients (26.3%) were in the 40–49 years age group, followed by 21.1% in the 30–39 years group. Patients aged 50–59 years constituted 18.4% of the study population, while both the 20–29 years and 60–69 years age groups accounted for 13.2% each. The lowest representation was observed in the 70–80 years age group, comprising 7.9% of the total cases. Table 2: Sex Distribution of Patients (n = 38) Sex Number of Patients Percentage (%) Male 28 73.7% Female 10 26.3% Total 38 100% Among the 38 patients included in the study, the majority were male, accounting for 73.7% (28 patients), while females constituted 26.3% (10 patients). Table 3: Mechanism of Injury (n = 38) Mechanism of Injury Number of Patients Percentage (%) Road Traffic Accidents 28 73.7% Falls 10 26.3% Total 38 100% In this study, road traffic accidents emerged as the most common mechanism of injury, accounting for 73.7% (28 cases) of distal one-third femoral shaft fractures. Falls were responsible for the remaining 26.3% (10 cases) Table 4: Intraoperative Data Analysis (n = 38) Parameter Mean ± SD Mean Duration of Surgery (minutes) 92.6 ± 15.4 Mean Intraoperative Blood Loss (ml) 210.0 ± 40.0 The intraoperative data analysis of the 38 patients in our study revealed that the mean duration of surgery was 92.6 ± 15.4 minutes, indicating a moderately consistent operative time across cases. The mean intraoperative blood loss was 210.0 ± 40.0 ml. Table 5: Infection Rate (n = 38) Type of Infection Number of Patients Percentage (%) No Infection 35 92.1% Superficial Infection 2 5.3% Deep Infection 1 2.6% Total 38 100% In our study, 92.1% (35 out of 38 patients) did not develop any postoperative infection. Superficial infections were observed in 5.3% (2 patients), while deep infection occurred in only 2.6% (1 patient). Table 6: Radiological Union Status at Follow-up (n = 38) Follow-up Duration Radiological Union Achieved Number of Patients Percentage (%) 3 months Yes 8 21.0% 6 months Yes 24 63.2% 9 months Yes 3 7.9% 12 months yes 1 2.6% Total – 36 100% Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1248 Radiological union was achieved in 36 out of 38 patients (94.7%) during the follow-up period. At 3 months, 21.0% (8 patients) showed evidence of union, while the majority—63.2% (24 patients)—achieved union by 6 months. A smaller proportion, 7.9% (3 patients), attained union at 9 months, and 2.6% (1 patient) showed union at 12 months. Table 7: Union Rate (n = 38) Union Status Number of Patients Percentage (%) United 30 78.9% Malunion 2 5.3% Delayed Union 4 10.5% Non-union 2 5.3% Total 38 100% In this study, 78.9% (30 out of 38 patients) achieved successful union of the distal one-third femoral shaft fracture. Delayed union was observed in 10.5% (4 patients), while malunion and non-union were each reported in 5.3% (2 patients). Table 8: Postoperative Complications (n = 38) Complication Number of Patients Percentage (%) Anterior Knee Pain 5 13.2% Knee Stiffness 3 7.9% Implant Failure 1 2.6% Superficial Infection 2 5.3% Deep Infection 1 2.6% Neurovascular Injury 0 0% Deep Vein Thrombosis (DVT) 0 0% Total with ≥1 Complication 9 23.7% Postoperative complications were observed in 23.7% (9 out of 38 patients). The most common complication was anterior knee pain, reported in 13.2% (5 patients), followed by knee stiffness in 7.9% (3 patients). Superficial infection occurred in 5.3% (2 patients) and implant failure and deep infection were each seen in 2.6% (1 patient). Table 9: Functional Outcomes (n = 38) Outcome Measure Mean ± SD / No. of Patients (%) Knee Society Score (KSS) 86.1 ± 7.2 Excellent (≥85) 22 (57.9%) Good (70–84) 11 (28.9%) Fair (60–69) 3 (7.9%) Poor (<60) 2 (5.3%) Lower Extremity Functional Scale (LEFS) 70.4 ± 8.3 Satisfactory Recovery (≥65) 30 (78.9%) Unsatisfactory Recovery (<65) 8 (21.1%) Functional outcomes in the study were evaluated using the Knee Society Score (KSS) and the Lower Extremity Functional Scale (LEFS). The mean KSS was 86.1 ± 7.2, with 57.9% (22 patients) achieving an excellent outcome (≥85), 28.9% (11 patients) classified as good (70–84), 7.9% (3 patients) as fair (60–69), and 5.3% (2 patients) having poor functional outcomes (<60). The mean LEFS score was 70.4 ± 8.3, and 78.9% (30 patients) demonstrated satisfactory recovery (≥65), while 21.1% (8 patients) had an unsatisfactory recovery (<65). Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1249 PRE OPERATIVE X-RAY. Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1250 POST OPERATIVE X-RAY AT DAY-1 Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1251 POST OPERATIVE X-RAY AT 18 MONTHS Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1252 POST OPERATIVE X-RAY AFTER IMPLANT REMOVAL Dr. Jaideep Singh et al. Functional and Surgical Outcome of Distal Third Shaft Fracture of Femur Treated with Distal Femoral Intramedullary Locking Nail (DFN), An Observational Prospective Study. Int. J Med. Pharm. Res., 6 (5): 1245‐1255, 2025 1253 PICTURE SHOWING LEFT KNEE JOINT IN FULL FLEXION and EXTENSION AFTER 18 MONTHS. Discussion: In my study comprising 38 patients with distal one-third shaft fractures of the femur, the majority of patients (26.3%) were in the 40–49 years age group, followed by 21.1% in the 30–39 years group. A similar age distribution pattern was observed in the study by Sah SK et al. (2023) [9], where the mean age was 30.47 years, with the most affected age group being the younger adult population, likely due to their increased exposure to high-velocity trauma. Our study also showed a clear male predominance, with 73.7% males and 26.3% females, consistent with the findings reported by Gomes N et al. (2024) [10], who noted that 82% of the patients in their study were males. This male predominance has been attributed to greater involvement of men in outdoor activities, vehicular travel, and occupational hazards, which increase the risk of high-energy trauma. Likewise, Tsegaye YA et al. (2024) [11] reported that distal femoral fractures predominantly affected males, aligning with our demographic profile. The consistent trend across studies suggests that distal femoral shaft fractures are more common among adult males in their productive age group, with road traffic