Costs and Outcomes After Primary and Revision Hip Replacements by Implant Bearing Materials: Analysis of 550 760...

We investigated 10-year revision risks, hospital admission costs, and quality of life for patients in the year after elective primary and revision total hip replacement (THR), overall and by implant bearing materials and fixation combination.

We analyzed linked National Joint Registry, Hospital Episode Statistics, and Patient Reported Outcome Measure databases for adults undergoing elective primary THR in England (2009-2018). Implants were classified by bearing material combinations (cobalt chrome and stainless steel, delta or alumina ceramics, and highly or nonhighly crosslinked polyethylene [HCLPE]) and fixation (cemented, uncemented, and hybrid). We estimated hazard ratios with flexible parametric survival models, and generalized linear models for costs and quality of life. Missing quality-of-life data were imputed using multiple imputation.

We analyzed 550 760 elective primary (mean age = 69, SD = 10.7) and 9590 subsequent revision THRs. On average, a primary THR costed, £10 365 (95% CI £10 350-£10 381); quality of life after primary was 0.786 (95% CI 0.785- 0.786), and 10-year revision risk was 2.4% (95% CI 2.08%-2.78%). First and second revisions costed, on average, £20 387 and £24 290, with mean quality-of-life scores of 0.609 and 0.502, respectively. Compared with cemented cobalt chrome and stainless steel on HCLPE, cemented delta-on-HCLPE, uncemented delta-on-HCLPE, and hybrid delta-on-HCLPE, alumina-on-HCLPE, delta-on-delta and alumina-on-alumina were associated with lower 1-year costs, improved quality of life, and lower 10-year revision risks.

Revision surgery costs double than that of an elective primary with drastically lower quality of life. Bearing materials and fixation were associated with varying 1-year costs, quality-of-life scores and revision risks. Although observational data may be affected by unmeasured confounding, our findings could help guide procurement decisions given changing trends in implant choice.