[Postoperative malrotation after closed reduction and intramedullary nailing of the femur: a retrospective 5-year analysis]

Abstract

Background: Minimally invasive treatment of diaphyseal femur fractures (DFF) with closed reduction and intramedullary nailing is a well established procedure. However, a femoral malrotation after intramedullary nailing is considered to be a substantial problem. Studies have described femoral malrotation (FMR) in 17-35 % after this procedure. Computed tomography (CT) of both femora is accepted as an objective, reproducible measurement method to determine a postoperative femoral malrotation. An anatomic reposition of the centreline of the femur remains of high importance since a malrotation > 15° can lead to a significant limitation of the range of motion (ROM) and to clinical symptomatic constraints.

Patients/material and methods: Between July 2007 and December 2011 patients with unilateral DFF were treated with closed reduction and intramedullary nailing. Exclusion criteria were defined as bilateral or prior treatment for femoral fractures, open epihyseal plate or pregnancy. In all cases a postoperative CT scan of the femora was conducted to analyse a femoral malrotation. The indication for a correction was posed in cases of a malrotation > 15°. The data were not randomised and evaluated retrospectively.

Results and conclusion: In total 94 patients with unilateral DFF were included. 21 female and 73 male with an average age of 33.15 ± 14.04 years (range 14-94). In the postoperative CT scan an average FMR of 11.58 ± 9.41° (range 0-44°) was determined. In 15 cases (15.95 %), 10 male (13.7 %) and 5 female (23.81 %) a FMR > 15° (average: 23.66 ± 5.74°) was noticed. A subsequent surgery with a correction in average of 17.53 ± 6.83° was performed. After the correction the malrotation averaged 6.07 ± 5.61°. The results support the existing data that the treatment of DFF with closed reduction and intramedullary nailing may lead to a significant femoral malrotation despite a precise intraoperative monitoring. The data demonstrate that nearly 15 % of all patients appear after closed reduction and intramedullary nailing with a femoral malrotation greater than 15°. A routinely utilised postoperative CT scan provides additional information to discover an occult malrotation.

Conclusion: In spite of diligent attendance to the femoral torsion intraoperatively in DFF a significant femoral malrotation may result after closed reduction and intramedullary nailing. To prevent a limitation of ROM and clinical constraints a routinely performed postoperative CT scan with a adequate surgical correction is recommended.