The Cumulative Risk of Re-dislocation After Revision THA Performed for Instability Increases Close to 35% at 15 years

A retrospective analysis was conducted on 539 hips undergoing revision total hip arthroplasty done for instability to report the cumulative risk and factors associated with re-dislocation and re-revision. The cumulative risk of re-dislocation and re-revision for all cause was 34.5% and 45.9% at 15 years, respectively. Multiple variable analyses revealed history of 2 or more previous surgeries, use of head size less than 36 mm, and cup retention to be risk factors for re-dislocation and re-revision. The use of a constrained liner was protective against re-dislocation but was not associated with a lower re-revision rate. Understanding the risk factors associated with re-dislocation or re-revision may help with perioperative decision making in order to decrease the high failure rate seen in this study.