Introduction: The incidence of hip fracture continues to increase as the elderly population increases, as a result of the extension of the average life span. Intertrochanteric fractures have been treated successfully by various methods, and now we are in an era where functional rehabilitation of patients to their preinjury levels is of prime importance. Reconstruction-type proximal femoral nailing is one of the surgical techniques used to treat intertrochanteric fractures. This implant faces less criticism than the previous ones, but it also has its own disadvantages. Aim: To analyze the factors that affect the functional and radiological outcomes of unstable intertrochanteric fractures treated by proximal femoral nailing and to identify the factors responsible for an abnormal gait pattern after union in some patients. Materials and Method: Forty-two patients treated in our facility who were categorized as having unstable intertrochanteric fractures were followed up until radiological union was achieved and 16 patients who had abnormal gait patterns were further studied to find the factor responsible. Tip Apex Distance, lateral screw sliding/collapse, screw position in the neck, initial and final neck-shaft angles, quality of reduction by the modified Fogagnolo et al. criteria and functional outcomes based on Harris Hip Score were analyzed. Results: The average Harris Hip Score in our study was 83.8. Thirty-eight patients did not have any complications, but 16 our patients had abnormal gait patterns at the final follow-up. The reason for the abnormal gait pattern was secondary varus collapse caused by excessive lag screw sliding. Conclusion:The initial quality of reduction as recommended by Fogagnolo is the key factor to achieve a favorable outcome. Proximal femoral nail helps in early return to their preinjury status in most of the patients. It also prevents the varus collapse in unstable intertrochanteric fractures, given the screws are positioned ideally.