Acetabular rim pathology secondary to congenital hip dysplasia in the adult. A radiographic study.

Major rim pathology is a precursor of osteoarthritis of the hip secondary to residual acetabular dysplasia. The symptoms are acute pain in the groin and impaired function; the anatomopathologic lesions consist in avulsions of the labrum from the bony rim, and separated bone fragments or "Os acetabuli", as well. A detailed radiographic, comparative inquiry to assess the preoperative morphology of 178 dysplastic hips which underwent a multiplanar periacetabular osteotomy was undertaken. The study showed that the 37 hips with a labral avulsion had a less pronounced anterior and lateral insufficiency of the acetabulum and a less pronounced lateral subluxation than dysplastic hips without these lesions. No specific radiologic features could be found in the 23 hips with bony fragments of the acetabular rim. The instability of the joint exerts abnormal stress on the acetabular rim which tends to tear it. This condition leads to rapid arthrotic degeneration of the hip; early diagnosis increases our ability to preserve the integrity of the joint through reliable reconstructive surgery.