LONG TERM FOLLOW-UP OF FREE VASCULARIZED FIBULAR GRAFTING FOR OSTEONECROSIS OF THE FEMORAL HEAD

Abstract

Introduction: The purpose of this study was to evaluate the clinical and radiographic long term follow-up results of vascularized fibular grafting (VFG) as a joint preserving procedure for osteonecrosis of the femoral head (ONFH).

Materials and Methods: Between October 1979 and December 1992, 97 hips in 89 patients with ONFH that had follow-up for at least 10 years (range: 10 years – 21 years) were evaluated. The mean age at the time of operation was 34 years. There were 49 hips with Ficat stage II radiographic changes and 48 hips with stage III disease. The disease was associated with consumption of alcohol in 19 hips, trauma in 17, and the use of steroids in 7. In the remaining 54 patients, the condition was idiopathic.

Results: Overall satisfactory results, including excellent, good or improved by 10 points, were seen in 78 hips (80.4%) clinically, and 63 hips (64.9%) showed radiographic improvement or no change.†Radiographically, new bone formation and remodeling was found in 32 hips; and no further progression of necrosis in 31 hips while progression of collapse was found in 34 hips. There were only 9 conversions to total hip anthroplasty (THA) at the last follow-up. By Kaplan-Meier survivorship analyses, there was a significant lower rate of conversion to THA in patients who were less than 35 years. The probability of conversion to THA was not significantly related to etiology, radiologic stage, or location of involvement of the necrosis.

Discussion: VFG not only has an excellent new bone formation and remodeling capacity, but also is one of the highly recommended joint preserving procedures in symptomatic ONFH in younger patients with early collapsed disease. Furthermore, femoral head replacement can be avoided or at least postponed in advanced stages of disease in the younger population.