THE UNREAMED AO FEMORAL NAIL IN THE TREATMENT OF SUBTROCHANTERIC FRACTURES

Abstract

We present a retrospective clinical and radiological review to assess the use of the AO unreamed femoral nail and spiral blade in the treatment of subtrochanteric fractures. Treatment of the subtrochanteric fracture remains a challenge. A combination of high stress concentration, poor cortical bone quality and comminution leads to a high incidence of problems. The abovementioned implant has been recommended for use in such fractures. However, several authors have reported mechanical failure and spiral blade migration. We have used the unreamed femoral nail since 1996 in 65 femoral fractures, and of these 32 were subtrochanteric fractures. A retrospective clinical and radiological study was undertaken to assess the use of the implant.

Clinical notes and radiographs were obtained for patients with subtrochanteric fractures treated with the AO unreamed femoral nail from November 1996 to November 1999. Fracture pattern was classified according to Seinsheimer. Assessments were made of callus formation and fracture healing. Any complication or implant failure was noted.

Thirty-two patients required an unreamed femoral nail. There were 20 females and 12 males, with an average age of 75 years. There were 16 fractures due to a fall, 15 pathological fractures, and one due to a car accident. Classification was: Type I: 6; Type II: 13; Type III: 6; Type IV: 3; Type V: 1. Mean follow-up was five months (range 3 to 18). Eight deaths occurred within one month. There were two pain-free non-unions, one revision with bone graft for non-union, and one spiral blade back out. No breakage of implants occurred.

We found that this implant provides stable fixation in these difficult fractures if adequate reduction is obtained. We have not experienced the implant failures reported in other series. We recommend the use of the implant, especially in those patients who are elderly or have pathological fractures.