Recurrent posttraumatic dislocation of the hip. A report of two cases and review of the literature.

Posttraumatic recurrent posterior hip dislocations were observed in two adult patients. In neither case was there evidence of acetabular dysplasia, paralysis, or infection. In both cases the only significant abnormality discovered was a marked posterior capsular redundancy. In the second case this was clearly shown by a computed tomography (CT) arthrogram. In both instances plication of the posterior capsule prevented further dislocations; however, the second patient developed massive heterotopic ossification around the involved joint and osteonecrosis of the femoral head. Investigation with CT arthrography of patients sustaining one or more dislocations in response to minimal trauma aids in evaluation of capsular abnormalities that may be surgically correctable.