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Treatment of Osteonecrosis of the Femoral Head with Free Vascularized Fibular Transfer

Thirty-one free vascularized fibular bone grafts were performed for treatment of osteonecrosis of the femoral head in 26 patients. Twenty-four men and 2 women ranged in age from 16 to 48 years (mean, 32 years). Twenty-one patients had unilateral disease. Five patients had bilateral disease and underwent staged bilateral free vascularized fibular grafts 3 months apart. Associated etiological factors included alcohol (9 patients), steroid use (7 patients), and trauma (1 patient). The condition was considered idiopathic in the remaining 9 patients. Radiological staging by Ficat included stage I in 1 hip, stage II in 15 hips, stage III in 14 hips, and stage IV in 1 hip. A skin island flap was used for monitoring purposes to check the patency of blood flow to the grafted fibula. One flap failed by venous occlusion and was left as a nonvascularized bone graft. Thirty hips were followed. Pain was relieved in 28 hips (93.3%) and aggravated in 2 hips (6.7%). On radiographic evaluation, 26 hips (86.7%) demonstrated excellent preservation of the femoral head contour. Progressive collapse of the femoral head (>1–2 mm) occurred in two hips, with 1-miri depression in one hip with stage III disease and 2-mm collapse in one hip with stage IV disease. Follow-up ranged from 12 to 40 months (mean, 21 months). In conclusion, even in this relatively short follow-up period, the free vascularized fibular bone graft is an excellent treatment modality for preserving the femoral head and relieving symptoms in patients with osteonecrosis of the femoral head.