Introduction The art of treating femoral shaft fractures is a deli- cate balance between restoration of limb length and align- ment, and at the same time achieving early mobilization of the limb. This is, however, prevented by strong muscular forces, which become specifically important when the frac- ture is either proximal or distal. Various treatment modalities have been used to treat these fractures with Intramedullary (IM) nailing being the gold standard. IM nails are weight sharing implants which allow immediate weight bearing after static locking even in unstable fractures. They have the advantage of providing greater fatigue strength, better stability in all planes special- ly if locking screws are used and providing reamed bone at the fracture site. 1-5 Intramedullary fixation may be categorized biome- chanically as dynamic or static. The decision between using static and dynamic nail is dictated by the anatomical level; fracture pattern and the comminution of the fracture. Comminution of the fracture is most commonly categorized by the method of Winquist and Hansen. 6 Surgical judgment dictates what type of IM fixation is needed. Intramedullary interlocking nailing is a new surgical technique introduced in our country less than a decade ago. Despite it being a technically simple procedure in expert hands we experi- enced few difficulties in mastering its technique. This study is an audit of our initial 89 cases where we will analyze our outcome and surgical errors in their treatment. Patients and Methods It is a retrospective study from January 1993 to December 1998 in which charts of all the patients with acute femoral shaft fractures treated with IM nailing at the Aga Khan University Hospital were reviewed. All adult patients with acute femoral shaft fractures were included. The patients having a follow-up of less than six months, with femoral shaft fractures treated by K-nails, ender rods, or conservatively were excluded. Pathological fractures and nailing done for nonunion were also excluded from the study. The initial study population was 117 but 28 patients were excluded because of the above reasons. The final study population was 89 patients. A comprehensive Performa was developed to record the data from the files and all the x-rays of the patient. The age ranges were from 15 to 70 years. The aver- age age was 36 years and most of them were younger patients. There were 73 males and 16 females. Fifty-three percent of patients had right femoral shaft fractures, while 47% had the left side involved. The mechanism of injury was road traffic accidents in 63 (70.8%) patients; fall in 16 (17.9%) and gun shot wounds in 10 (11.2%) patients. Sixty- six (74%) patients had closed fractures while 23(26%) had open fractures. Among them, 3 (3.3%) had grade I; 5 (6%) had grade II; 9 (10%) had grade IIIA; 4 (4.4%) had grade IIIB; and 2 (2.2%) had grade IIIC open fractures. In our Treatment of acute fractures of the Femoral Shaft with reamed Intramedullary Interlocking AO Nails M. Umer, A. K. Niazi, D. Hussain*, M. Ahmad** Departments of Orthopedic Surgery, General Surgery* and Research**. Aga Khan University Hospital, Karachi. Abstract Objective: To review and audit our experience with closed intramedullary interlocking nailing for acute femoral shaft fractures. Methods: All patients admitted to The Aga Khan University Hospital, over the last six years and with a minimum follow-up of twelve months, with acute fractures of the femoral shaft were included in the study. All patients treat- ed for established non-unions and infections or with pathological fractures were excluded from the study. Results: There were 89 fractures, 74% of whom were closed and 50% were associated with other orthopedic injuries. Most of these were younger patients involved in high velocity road traffic accidents.The union rate was 88% with 4.4% of fractures going into non-union. The remaining 8% of the fractures went into a phase of delayed union, but ultimately united, making the overall success rate to be 95.6%. The mean time for union was 11.5 weeks. At the final clinical follow-up, 4% of the patients had minor pain, 7% had limp, 4% had leg length discrep- ancy of more than 2cm and 4% had decreased range of motion at the hip or knee joints. We had a 4% rate of superficial infection. There were 3 cases of pudendal nerve neuropraxia and 2 cases of deep vein thrombosis. Conclusion: Intramedullary Interlocking nailing is a safe and effective treatment modality for acute fractures of the femoral shaft. Proper surgical decision making regarding static versus dynamic mode of locking can avoid problems of delayed union (JPMA 54:423;2004).