Factors influencing revision risk following 15 740 single-brand hybrid hip arthroplasties : a cohort study from a National Joint Registry

This retrospective cohort study of a National Joint Registry data examines survival time to revision following the commonest brand of primary hybrid THA, exploring risk factors independently associated with failure. Overall 5-year revision was 1.56%. In the final adjusted model, revision risk was significantly higher with standard polyethylene (PE) liners (metal-on-PE: hazard ratio [HR]=2.52, P=0.005, ceramic-on-PE: HR=2.99, P=0.025) when compared to metal-on-highly-cross-linked (XL) PE. Risk of revision with ceramic-on-ceramic bearings was borderline significant (HR=1.86, P=0.061). A significant interaction between age and acetabular shell type (solid or multi-hole) was found (P=0.022), suggesting that solid shells performed significantly better in younger patients. In summary, we found that there were significant differences in implant failure between different bearing surfaces and shell types after adjusting for a range of covariates