Free Vascularized Proximal Fibular Epiphyseal Transfer For Hip Reconstruction Following Septic Necrosis In Children

Abstract

Background: Septic necrosis of the femoral head and neck in children represents a challenging problem. Several reconstructive techniques have been described but with disappointing long-term results. Vascularized epiphyseal transfer utilizing the proximal fibula have been successfully used for reconstruction of the proximal humerus and distal radius and only scarcely used for hip reconstruction. This cohort represents the largest reported series of epiphyseal transfer for hip reconstruction following septic necrosis in children. Methods: A total of 18 patients with an average age at surgery of 5.4 years were included. The average follow-up was 3.6 years (range 2.3 to 6.8 y). Results: Transient postoperative foot drop was observed in 4 patients. Radiographic resorption of the transferred fibula occurred in 2 cases. Longitudinal growth averaged 7.3 mm/year, and the physis width increased by an average of 2.7 mm/year. The rate of longitudinal growth was fastest after the age of 10 years (18.5 mm/y), which coincides with the pubertal growth spurt. All successful transfers had an open growth plate on final follow-up radiographs. Ten patients had limb length discrepancy of an average 2.8 cm (range 1 to 8 cm). Thirteen patients had satisfactory functional according to the criteria of Hunka et al. Three patients had unsatisfactory results; one had painful nonunion at the fibula-femur junction, and the other two had limited flexion range of 45 degrees. The average postoperative neck-shaft angle was 96.4 degrees which decreased by an average of 8 degrees at the final follow-up. Three patients underwent a valgus subtrochanteric osteotomy to correct a severe varus deformity. The final neck-shaft angle correlated significantly with the functional results where it averaged 96 degrees in the satisfactory group and 57 degrees in the unsatisfactory group. Conclusion: Vascularized epiphyseal transfer presents a promising treatment for children with septic necrosis of the femoral head and neck in whom other methods have failed to provide satisfactory long-term results. We recommend the procedure be done before the age of 5 years for optimum results. Level of Evidence: Level—IV.