Folded free vascularized fibular grafts for the treatment of subtrochanteric fractures complicated with segmental bone defects

BACKGROUND: Subtrochanteric fractures of the femur complicated with segmental bone defects are uncommon injuries and challenging to manage. We evaluated the effect of reconstructing extensive bone defect in the subtrochanteric area (mean, 6.9 cm) with folded free vascularized fibular graft (FVFG). METHODS: Between 2001 and 2007, 14 cases of subtrochanteric fractures complicated with huge bone defects treated by folded FVFG transfer in our hospital were retrospectively reviewed. The defect was reconstructed by folded FVFG transfer and locking plate stabilization in 10 patients with no sign of infection at admission (group 1). In the other four patients presented with infections (group 2), the defect was reconstructed by folded FVFG transfer and external fixator fixation. The average follow-up period was 67.4 months. RESULTS: Bone union was achieved in all of the cases at an average of 5.4 months (range, 4–6 months). Primarily, bone union was achieved in all of the cases in group 1, but one stress fracture occurred in group 2. The full weight bearing time was 5.4 months (range, 5–6 months) in group 1 and 8.5 months (range, 8–9 months) in group 2. Seven patients in group 1 had the locking plate removed in an average of 27 months (range, 18–38 months). In group 2, the external fixator removal time was 13 months (range, 10–18 months). There was no varus deformity at the final follow-up in group 1. The neck-shaft angle measured during the postoperative period and at final follow-up was 129.6 degrees and 129.4 degrees, respectively. In group 2, the neck-shaft angle at the final follow-up was significantly less than the angle measured at the postoperative period (115.5 vs. 129.5 degree, p = 0.021). The range of motion of the hip and knee joint (extend and flex) was 100 degrees or more in all patients at the final follow-up. CONCLUSIONS: The results of this study showed that huge subtrochanteric bone defects reconstructed by folded FVFG and locking plate were highly successful in achieving bone union, reducing risks of postoperative stress fracture and preventing malunion. When huge bone defects in the subtrochanteric area complicated with acute or chronic infections, the technique of external fixator offers an alternative to reconstruct the stability of the proximal femur after folded FVFG. However, because of the inadequate stabilization, the risks of varus malunion and postoperative stress fracture could be increased after external fixator fixation. LEVEL OF EVIDENCE: V, therapeutic study.