Transtrochanteric anterior rotational osteotomy for osteonecrosis of the femoral head in patients 20 years or younger

BACKGROUND:: For young patients with osteonecrosis of the femoral head, especially those younger than 20 years, a joint-preserving operation may be one of the surgical treatment options to be considered. We investigated the clinical and radiological results of transtrochanteric anterior rotational osteotomy for the treatment of osteonecrosis of the femoral head in patients 20 years or younger. METHODS:: Between 1976 and 2001, a transtrochanteric anterior rotational osteotomy was performed in 28 hips of 23 patients aged 20years or younger with osteonecrosis of the femoral head. Among them, 27 hips of 22 patients with a minimum follow-up duration of 2years were investigated (follow-up rate, 96.4%). They included 7males and 15 females with a mean age of 16 years at the time of surgery. The mean follow-up period was 14.7 years (range, 2.0-31.7 years). The clinical assessment was made based on the Merle d'Aubigné-Postel score. The postoperative intact ratio, joint-space narrowing, and progression of collapse were all investigated radiographically. RESULTS:: Two (7.4%) of the 27 hips required total hip arthroplasty because of restrictions in the range of motion, whereas the original hip joints in 25 (92.6%) of the 27 hips were preserved at the time of final follow-up. The mean preoperative Merle d'Aubigné-Postel score was 10.4 points, which improved to 15.9 points at the final follow-up (P < 0.0001). The mean postoperative intact ratio was 49.8% (range, 30-100). Five (18.5%) of the 27 hips had a progressive joint-space narrowing, but progression of the collapse was not observed in anyhips. CONCLUSIONS:: Transtrochanteric anterior rotational osteotomy appears to be a useful joint-preserving operation for patients younger than 20years.