Comparison of 20-year results of total hip arthroplasty using first-generation annealed highly cross-linked polyethylene and zirconia heads in patients aged ≤ 50 and > 50 years

This study investigated 20-year outcomes of total hip arthroplasty (THA) using zirconia heads on annealed highly cross-linked polyethylene (HXLPE) liners, comparing patients aged ≤ 50 and > 50. We reviewed 117 hips (100 patients) who underwent cementless THA between 2001 and 2004. After excluding follow-up < 15 years, 22 hips (≤ 50) and 61 hips (> 50) were analyzed. Merle d’Aubigné and Postel score, University of California, Los Angeles activity score, Kaplan–Meier survivorship, femoral head penetration, and oxidative degradation in retrieved liners were evaluated. Patients ≤ 50 had higher activity. Three revisions for infection occurred in the > 50 group; none due to wear. Survivorship was 93% overall, 100% in ≤ 50, and 91% in > 50, with no difference. Steady-state wear rate was 0.01 mm/year in both groups. Retrieved liners showed oxidation. Zirconia-on-annealed HXLPE THA showed excellent 20-year wear resistance and survivorship, with comparable outcomes between ≤ 50 and > 50 groups.