USE OF CONSTRAINED SOCKETS IN REVISION THA: MORE PROBLEMS THAN THEY SOLVE – AFFIRMS

Instability after total hip arthroplasty is the primary cause for revision surgery and is a frequent complication following revision surgery for any reason (Bozic et al, JBJS 2009). Surgical management of the unstable hip has not been uniformly successful with the best results occurring in those hips in which an identifiable cause of instability can be determined (Daly & Morrey, JBJS 1992). It was these sobering findings that led to the development of and increased use of constrained acetabular components.While the results of revision surgery for instability using constrained components have been encouraging (Shapiro, Padgett, Sculco J Arthroplasty 2003) with a re-dislocation rate of less than 3%, reoperation for other reasons have noted to increase with time. The commonly used tripolar configuration has been susceptible to bearing damage at both the inner and outer bearing surface by the nature of the constrained mechanism (Shah, Padgett, Wright, J Arthroplasty 2009). In addition, we have noted instances...