Rotational acetabular osteotomy for hip dysplasia: 61 hips followed for 8-15 years.

We operated on 54 patients (61 joints) with rotational acetabular osteotomy (RAO) due to dysplasia of the hip with pre- or early-stage osteoarthritis/arthrosis. The mean follow-up was 11 (8-15) years. The Merle d'Aubigné median score increased from 14 to 15. In 2 patients (2 joints), the score decreased from 15 to 13. Progression of arthrosis was seen in 6 joints on the radiographs at follow-up. Kaplan-Meier survivorship analysis predicted an 89% (95% confidence interval 80-99) prevention of worsening of arthrosis at 10 years. Postoperative joint congruency was a risk factor for progression of arthrosis.