Treatment of recurrent dislocation associated with impingement after revision total hip arthroplasty

The authors report a case of total hip replacement in which, following several revision operations ending up in a Girdlestone arthroplasty, a patient presented recurrent episodes of posterior dislocation of his total hip prosthesis after revision using an antiprotrusio cage. The main causes for dislocation were anterior impingement of the neck against the anterior wall of the antiprotrusio cage and slackness of the periarticular musculature, due to shortening and reduced femoral offset. In order to avoid further major reconstruction and minimise the risk of infection recurrence, a limited revision operation was performed to address the factors responsible for the instability: the anterior wall of the antiprotrusio cage was removed and an extension module was added to the femoral component. Good stability of the arthroplasty was achieved with this limited procedure.