Highly Crosslinked Polyethylene in Posterior-Stabilized Total Knee Arthroplasty: In Vitro Performance Evaluation of Wear, Delamination, and Tibial Post Durability

Recent advances in total knee arthroplasty (TKA) include the development of highly crosslinked polyethylene (HXPE). To assess the suitability of using HXPE in posterior-stabilized TKA, knee simulator wear testing and a novel tibial post durability test were performed on a modern posterior-stabilized implant design with both conventional polyethylene (CPE) and HXPE materials. The laboratory testing reproduced clinically relevant wear and tibial post damage mechanisms. For the designs tested, wear volume was reduced by 67% to 75% for aged HXPE compared with aged CPE. Components of HXPE also demonstrated superior tibial post durability compared with the CPE design, despite the use of unaged material to represent best-case CPE tibial post strength. With appropriate design considerations, HXPE can be successfully incorporated into a posterior-stabilized TKA.