Highly Crosslinked Polyethylene Is Associated With a Lower Revision Risk Out to 20-Year Follow-Up Versus Conventional Polyethylene in Total Knee Arthroplasty.

Background: Evidence of any benefit in the long-term performance of highly crosslinked polyethylene (HXLPE) for total knee arthroplasty (TKA) is lacking. We sought to evaluate revision risk for HXLPE versus conventional polyethylene (CPE).

Methods: Data from a US-based health care system's Total Joint Replacement Registry were used to conduct a cohort study. Adult patients who underwent primary fixed-bearing TKA with patella resurfacing for osteoarthritis were included (2001 to 2023). The final study sample included 232,527 TKAs: 105,028 HXLPE and 127,499 CPE. The primary outcome was revision out to 20-year follow-up, and revision for any aseptic reasons as well as for wear and loosening were the secondary outcomes. Multivariable Cox regressions were used to evaluate revision risk by polyethylene with covariate adjustment.

Results: At 20-year follow-up, crude revision incidence was 6.0% for HXLPE and 6.1% for CPE. In adjusted analyses, a lower revision risk (hazard ratio [HR] = 0.93, 95% confidence interval [CI] = 0.88 to 0.98) was observed when comparing HXLPE with CPE. This lower risk was observed with other revision reasons evaluated (overall aseptic: HR = 0.93, 95% CI = 0.88 to 1.00; wear: HR = 0.75, 95% CI = 0.60 to 0.94; loosening: HR = 0.75, 95% CI = 0.67 to 0.84).

Conclusions: In this registry-based cohort study, 20-year revision incidence was approximately 6% regardless of polyethylene used. Still, we observed HXLPE to perform at least as well, if not better than CPE, at long-term follow-up in adjusted analyses, specifically for wear and loosening, supporting increased HXLPE use for TKA.

Level Of Evidence: Level III.