A retrospective review was performed on 27 consecutive patients with total hip arthroplasty (THA) following failure of internal fixation of fractures of the proximal femur. The results were comparable to primary THA in femoral neck fractures. Considerably less satisfactory results were obtained in THA in intertrochanteric fractures. Bone loss and medial displacement of the femoral shaft led to high incidence of intraoperative complications and postoperative dislocations. Extreme care must be taken to avoid fracture and penetration of the femoral shaft. Autograft, allograft, or head and neck replacement components should be available for reconstruction of the difficult cases.