Management of osteonecrosis of the femoral head with pedicled iliac bone flap transfer: A multicenter study of 2190 patients.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) often affects young active adults and leads to destruction of the hip joint and disabling arthritis. Several procedures have been developed to arrest the progress of osteonecrosis and postpone the procedure of total hip replacement especially in young patients. The aim of this multicenter study was to analyze the results of the use of the vascularized iliac bone flap transfer for management of ONFH.

METHODS: From January 1985 to December 2012, a total of 2190 patients (2690 hips) with the mean age of 43.15 years (ranging from 18 to 65 years) underwent hip-preserving surgery with the pedilced iliac bone flap transfer for management of ONFH with Ficat and Arlet stage II-IV in 8 hospitals. There were 1733 hips in stage II, 776 hips in stage III, and 181 hips in stage IV preoperatively. The complications were recorded. The outcomes were evaluated by radiograph, the Harris hip-scoring system (HHS).

RESULTS: Postoperative complications occurred in 128 patients (5.84%). Among them, 25 patients had deep venous thromboses, 16 patients had sensory deficits, 40 patients had superficial infection and hematoma, and 47 patients had wound dehiscence. A total of 1912 patients (2179 hips) were followed up with a median time of 12 years (ranging from 5 to 25 years). There were 1787 hips with no radiographic osteonecrotic progress during follow-up, while osteonecrosis progress was observed in 186 hips with stage II (13.1%), 170 hips with stage III (25.6%) and 36 hips with stage IV (36.4%; P < .001). Two hundred fifteen hips (9.87%) in 203 patients were converted to THA during follow-up, including 19 hips with stage II (1.34%), 162 hips with stage III (24.4%), and 34 hips with stage IV (34.3%).The mean HHS at the end of follow-up was significantly improved when compared to preoperative mean HHS (83.63 ± 5.03 vs. 66.54 ± 6.05, P < .001).

CONCLUSIONS: In this evaluation of a large series of cases, the vascularized iliac bone flap transfer showed good results for arresting the osteonecrosis progress and improving the hip function of patients with pre-collapse stages of ONFH.