Kahlenberg CA, Baral E, Lieberman LW, et al. - This study was sought to analyze a cohort of retrieved rotating hinge (RH) total knee arthroplasty implants of four different designs with an emphasis on the surface damage observed on the polyethylene components. Researchers ascertained whether variations in polyethylene damage existed among the designs, and if those differences could be explained by differences in design characteristics. They distinguished 72 RH implants from four manufacturers (DePuy LPS/SROM, Zimmer NexGen, Stryker Howmedica MRH, and Biomet Finn-OSS) removed at the time of revision performed between 2002-2017 in our institutional retrieval registry. As per the findings, no single implant design emerged as superior in terms of minimizing polyethylene wear damage. It was shown that polyethylene damage existed in various locations, but was not different in severity across designs, implying that there is no clear superior RH design that minimizes overall articular surface wear in comparison with other designs.