Revision for recurrent instability: what are the predictors of failure?

Dislocation is a common complication following total hip arthroplasty (THA). In this study, we evaluated treatment strategies in patients undergoing revision THA for instability. A total of 156 hips in 154 patients underwent revision THA for instability between 2000 and 2007 at our institution. Demographic data and surgical treatment used were analyzed to determine risk factors for failure. Revision treatments included acetabular components in 100 hips, liner exchange in 56 hips, and femoral and acetabular components in 13 hips. Thirty-three (21.2%) had further dislocation. Isolated liner revision (P = .004), previous revision arthroplasty (P < .05), and the use of a 28-mm femoral head were associated with higher failure rates. A total of 20.3% (12/59) of constrained liners failed. Isolated liner exchange, history of revision, and use of a 28-mm head were associated with failure in revision THA for instability.