Ontology highlight
ABSTRACT: Background
Highly crosslinked ultrahigh-molecular-weight polyethylene (XLPE) shows reduced wear in total hip arthroplasty compared to direct compression-molded polyethylene (compPE); however, minimal research evaluating polyethylene damage in XLPE tibial inserts in total knee arthroplasty exists.Questions/purposes
We evaluated damage and material properties in retrieved XLPE components at midterm (??2.5 years) follow-up.Methods
We identified 19 XLPE tibial inserts with ??30 months in vivo using our institutional review board-approved implant retrieval system; 19 compPE retrieved inserts were matched based on age at index surgery, body mass index, sex, and length of implantation. Articular surface damage was assessed using a subjective grading system. Swell ratio testing and Fourier-transform infrared spectroscopy were used to measure crosslink density (XLPE) and oxidation (XLPE, compPE), respectively, at loaded and unloaded surface and subsurface regions.Results
CompPE inserts had higher overall damage than XLPE inserts, specifically at the post of posterior-stabilized inserts. The XLPE inserts had lower crosslink density at the loaded surface (0.159 mol/dm3) than either unloaded region (0.183 mol/dm3). CompPE peak oxidation index (OI) was greater than XLPE peak OI in the loaded and unloaded surface regions (1.67 vs. 0.61 and 1.38 vs. 0.46, respectively).Conclusions
Surface damage and oxidation are reduced in XLPE inserts compared to compPE at midterm follow-up. Peak OI greater than 1.0 in the compPE group suggests that mechanical-property degradation had occurred, a likely cause for increased damage. Longer-term retrievals will determine whether these trends continue. Based on midterm results, XLPE shows an advantage over compression molded PE in total knee arthroplasty.
SUBMITTER: Stavrakis A
PROVIDER: S-EPMC6031546 | biostudies-literature | 2018 Jul
REPOSITORIES: biostudies-literature
HSS journal : the musculoskeletal journal of Hospital for Special Surgery 20180326 2
<h4>Background</h4>Highly crosslinked ultrahigh-molecular-weight polyethylene (XLPE) shows reduced wear in total hip arthroplasty compared to direct compression-molded polyethylene (compPE); however, minimal research evaluating polyethylene damage in XLPE tibial inserts in total knee arthroplasty exists.<h4>Questions/purposes</h4>We evaluated damage and material properties in retrieved XLPE components at midterm (≥ 2.5 years) follow-up.<h4>Methods</h4>We identified 19 XLPE tibial inserts with ≥ ...[more]