Free vascularized fibular bone grafting in the management of femoral neck nonunion in patients younger than fifty years.

Abstract

The incidence of nonunion and osteonecrosis after femoral neck fracture has been well documented. In older patients implant arthroplasty is well established as an acceptable treatment of these problems. However, in the younger population alternatives to implant arthroplasty are favored to preserve the femoral head. Surgical treatments for nonunion of the femoral neck include osteotomy, nonvascularized bone grafting, muscle-pedicle bone grafting, and vascularized bone grafting. The purpose of this study is to examine the results of free vascularized fibular grafting as a treatment of nonunion of the femoral neck in patients younger than fifty years. Twenty-two consecutive patients underwent vascularized bone grafting for nonunion of the femoral neck after failed internal fixation between 1984 and 1998. The mean age of the patients was 28.7 years. There were thirteen male and nine female patients. The mean interval between internal fixation and free vascularized fibular grafting was 18.3 months. The average follow-up to date is 84.7 months (range 29 to 195 months). Twenty of twenty-two nonunions healed. Two patients required an additional procedure to facilitate union; one patient had iliac crest bone grafting at four months postoperatively and another underwent muscle-pedicle grafting at six months postoperatively. The average time to union for all patients was 9.9 months (range 3 to 23 months). Progression of osteonecrosis of the femoral head occurred in thirteen patients. However, successful long-term salvage of the femoral head was achieved in twenty of twenty-two patients, with an average Harris hip score of 78.9. Four patients required hardware removal or exchange for intraarticular migration with no long-term clinical sequelae. Rates of complications, such as nonunion and osteonecrosis, after femoral neck fractures in young patients have been reported to be as high as 86 percent. Treatments such as osteotomy, muscle-pedicle bone grafting, nonvascularized bone grafting, and vascularized bone grafting have reported variable results. Based on the results reported in this study, vascularized fibular bone grafting compares favorably with a high union rate (91 percent initially, 100 percent after secondary procedures) and successful long-term salvage of the femoral head in 91 percent of the patients. Free vascularized fibular bone grafting represents a promising solution for this difficult problem.