The purpose of this study was to analyze the results of treating subtrochanteric femoral fractures with proximal femoral nail antirotation (PFNA).

Twenty five consecutive patients diagnosed with subtrochanteric femoral fractures underwent intramedullary fixation using PFNA and followed-up for over 12 months. According to the Seinsheimer's classification, there were 2 type IIA, 9 type IIB, 2 type IIIA, 3 type IV and 9 type V. According to the AO classification, there were 10 type A, 9 type B and 6 type C. There were 16 cases of closed reduction group and 9 cases of limited open reduction group. Retrospectively, radiological outcomes were assessed at the union period, change of neck shaft angle, tip-apex distance, Cleveland index, sliding of lag screw and complication.

Union was achieved in 23 of 25 cases, over an average of 17 weeks. Limb length shortening below 2 cm occurred in 7 patients. The Cleveland index was shown in 80% of 5, 6, 8 and 9 zone; the tip apex distance was 19.6 mm; the mean sliding distance was 4.4 mm; and the mean change of femur neck and shaft angle was varus 3 degree at the final follow-up. Complications included 3 cases of delayed union and 2 cases of nonunion.

With its early bony union, ambulation, rehabilitation and low complication, PFNA is a useful and reliable choice for the treatment of subtrochanteric fractures of the femur. Limited open reduction and additional fixation such as cable grip are recommended if it is difficult to obtain anatomical reduction by closed reduction.