Bernese periacetabular osteotomy. : Indications, technique and results 30years after the first description

Abstract

The Bernese periacetabular osteotomy (PAO) is asurgical technique for the treatment of (1)hip dysplasia and (2)femoroacetabular impingement due to acetabular retroversion. The aim of the surgery is to prevent secondary osteoarthritis by improvement of the hip biomechanics. In contrast to other pelvic osteotomies, the posterior column remains intact with this technique. This improves the inherent stability of the acetabular fragment and thereby facilitates postoperative rehabilitation. The birth canal remains unchanged. Through ashortened ilioinguinal incision, four osteotomies and one controlled fracture around the acetabulum are performed. The direction of acetabular reorientation differs for both indications while the sequence of the osteotomies remains the same. This surgical approach allows for aconcomitant osteochondroplasty in the case of anaspherical femoral head-neck junction. The complication rate is relatively low despite the complexity of the procedure. The key point for asuccessful long term outcome is an optimal reorientation of the acetabulum for both indications. With an optimal reorientation and aspherical femoral head, the cumulative survivorship of the hip after 10years is 80-90 %. For the very first 75patients, the cumulative 20-year survivorship was 60 %. The preliminary evaluation of the same series at a30-year follow-up still showed asurvivorship of approximately 30 %. The PAO has become the standard procedure for the surgical therapy of hip dysplasia in adolescents and adults.