Periacetabular osteotomy (PAO) is a well established method to treat hip dysplasia in the adult. There are, however, a number of complications associated with this procedure as well as a time related deterioration in the grade of osteoarthritis that can influence the long term result. It is essential that patients are fully informed as to the effectiveness of PAO, the likelihood of complications and their influence on the subjective outcome prior to giving consent for surgery. Generic outcome measures offer the opportunity to determine treatment efficacy and the influence on the outcome by complications.

60 PAOs on 50 patients were investigated retrospectively after a mean follow up of 7.4 years. The patients’ self reported assessment of health and function was evaluated by the SF-36 and the WOMAC questionnaires at last follow-up. 40 healthy persons served as a control group.

The centre-edge angle improved from a mean of 8.7° to 31.5°. The weight bearing surface improved from a mean lateral opening of 8.7° to 4.2°. The degree of osteoarthritis improved in one case, remained unchanged in 20 and deteriorated in 17. There was a tendency of higher CE-angles towards a higher rate of deterioration, indicating that overcorrection may increase osteo-arthritic degeneration. 13 of the 60 interventions had no complications. Minor complications occurred in 25 (41%) interventions and in 22 (37%) at least one major complication occurred. SF-36 summary measure was 76.4 for PAO patients and 90.3 for the control group. Mean WOMAC score was 25.1. The severity of ectopic bone formation, incidence of postoperative peroneal nerve dysfunction and delayed wound closure did not influence the subjective result. Patients with major complications had a similar subjective outcome as patients with minor or no complications, but persistent dysesthesia due to lateral femoral cutaneous nerve dysfunction led to a worse subjective function as assessed with the WOMAC score.