Joint congruency in abduction before surgery as an indication for rotational acetabular osteotomy in early hip osteoarthritis.

We conducted a retrospective review of the results of rotational acetabular osteotomy (RAO) procedures in 92 hips of 89 patients (81 females and eight males) with early-stage osteoarthritis. In this study, we discuss the indications for this surgery based on the preoperative congruency in abduction. The mean postoperative follow-up was 12.2 (7-19) years. The mean age at operation was 32.5 (13-54) years. Two hips with apparent technical failure were excluded. During follow-up, the osteoarthritic stage remained unchanged in 76 hips (good group) and progressed in 14 hips (poor group). Preoperative joint congruency in abduction was excellent in 20 hips, good in 62, and fair in eight. All eight hips with fair joint congruency showed progression to osteoarthritis at follow-up. Patients without good congruency in abduction may experience progression of osteoarthritis after RAO procedures even in early-stage osteoarthritis.