Nonunion of subtrochanteric fractures: Comminution or Malreduction

OBJECTIVE This study aimed to investigate the impact on nonunion of the extent of comminution and postoperative displacement in patients surgically treated for subtrochanteric fractures. METHODS From 2008 to 2013, 44 patients with subtrochanteric fractures underwent surgery and follow-up. Retrospective data collection showed that it had 32 male and 12 female. Their mean age was 45 years. The case distribution according to Seinsheimer classification was as follows: IIA,8; IIB, 5; IIC, 7; IIIA, 8; IIIB, 3; IV, 9; and V, 4. Cephalomedullary nails were used in 28 cases; ordinary nails, in 9; and plates, in 7. After surgery, the fractures were evaluated for displacement on anteroposterior (AP) and lateral radiography. RESULTS Of the 44 patients, 37 achieved union from primary surgery at a mean time of 8.4 months. Five cases did not show union within the follow-up period. Two cases of nail breakage were diagnosed as non-union. Among the non-union cases, two were Seinsheimer classification IIIA; 3, IV; and 2, V. Displacement was observed on the lateral and A Pradiographs of 4 cases, on only the lateral radiographs of two cases, and in neither radiograph of one case. The risk of non-union was approximately 15.4 and 24.2 times higher when displacement was observed on the AP (95% confidence interval [CI]: 1.33-176.82) and lateral images (95% CI: 1.76-335.67), respectively. CONCLUSION When displacement occurred after surgical treatment for subtrochanteric fractures, the risk of nonunion increased owing to the difficulty achieving stable fixation.