CORR Insights®: Retrieval analysis of sequentially annealed highly crosslinked polyethylene used in total hip arthroplasty.

Abstract

I n vivo oxidation of highly crosslinked polyethylene (HXLPE) components, particularly among annealed polyethylenes, resulted in the development of the so-called ‘‘secondgeneration HXLPEs’’ (defined as HXLPEs that incorporate manufacturing modifications to improve minor deficiencies with unclear consequences). Among those, sequentially annealed polyethylenes were designed to decrease the detected in vivo oxidation that could adversely affect the durability of these components in vivo. Radiostereometric analysis of THAs using sequentially annealed secondgeneration HXLPE liners suggested that head penetration and threedimensional wear remained low at 5 years [1]. However, recent retrieval studies [2, 3] stressed the persistence of oxidation in the HXLPE in the face of remelting, annealing, or sequential annealing. While in vivo oxidation was higher in the tibial retrievals than in the acetabular liners, the debate regarding this topic continues. The location and mechanical effects of residual oxidation that develops in vivo may influence the risk of component failure, in particular in THAs.