Retrospective Long-Term Follow-Up Survival Analysis of the Management of Osteonecrosis of the Femoral Head With Pedicled Vascularized Iliac Bone Graft Transfer.

BACKGROUND:Osteonecrosis of the femoral head (ONFH) often affects young, active adults and leads to the destruction of the hip joint and disabling arthritis. Several procedures have been developed to prevent conversion to total hip arthroplasty (THA), especially in young patients who have a high rate of hip revision surgery. The aim of this long-term follow-up is to analyze the results of vascularized iliac bone flap transfer for ONFH treatment. METHODS:We retrospectively reviewed 856 patients (1006 hips) who accepted hip-preserving surgery with vascularized iliac bone grafting due to ONFH (Ficat and Arlet stages II-IV) from January 1985 to December 2012 at our hospital. Radiographic assessment was performed with the Ficat and Arlet system, clinical assessment was performed with the Harris Hip Score system, and quality of life was evaluated with the 36-Item Short Form Survey. The hips included 575 stage II hips, 382 stage III hips, and 49 stage IV hips. We defined clinical failure as conversion to THA or any other hip-preserving surgery because of hip symptoms. RESULTS:A total of 856 patients (1006 hips) were eventually followed up with an average time of 15 years (range 5-25). In total, 75 patients were lost to follow-up, and 105 hips were converted to THA. The average Harris Hip Score was 87.43 ± 6.42 points at the last follow-up, representing a great improvement compared to the 66.42 ± 6.52 points obtained preoperatively. The Kaplan-Meier survival analysis showed no difference in the 15-year survival rate between patients with stages II and III disease (using THA as an end point). However, the survival rate was lower for patients with stage IV disease than that for patients with stages II and III disease. The survival rate for patients in the glucocorticoid group was lower than that for patients in the idiopathic, alcoholic, and trauma groups. The Physical Component Summary scores ranged from 78 ± 10 to 85 ± 14 postoperatively compared to 30 ± 14 to 55 ± 15 preoperatively, and the postoperative Mental Component Summary scores (range from 34 ± 11 to 59 ± 12) were significantly higher than the preoperative scores (range from 72 ± 11 to 90 ± 10), representing great improvement in patient quality of life. Postoperative complications occurred in 86 patients (4.5%) during the follow-up, including 23 patients with deep venous thrombosis, 16 patients with meralgia paresthetica (which resolved), and 47 patients with secondary wound healing. CONCLUSION:The vascularized iliac bone flap grafting technique yields significant improvement (particularly in the precollapse disease stages in young patients) for restoration of the biomechanical support of the collapsed femoral head and reconstruction of the blood supply to the osteonecrotic area. This procedure allows these patients to avoid or delay the need for THA surgery.