title: Cost-utility of metal-on-metal hip resurfacing compared to conventional total hip replacement in young active patients with osteoarthritis.
abstract: BACKGROUND
  Metal-on-metal hip resurfacing arthroplasty (MoM HRA) has emerged as an alternative to total hip arthroplasty (THA) for younger active patients with osteoarthritis (OA). Birmingham hip resurfacing is the most common MoM HRA in Alberta, and is therefore compared with conventional THA.
  
  
  OBJECTIVE
  The objective of this study was to estimate the expected cost-utility of MoM HRA versus THA, in younger patients with OA, using a decision analytic model with a 15-year time horizon.
  
  
  METHODS
  A probabilistic Markov decision analytic model was constructed to estimate the expected cost per quality-adjusted life-year (QALY) of MoM HRA versus THA from a health care payer perspective. The base case considered patients with OA aged 50 years; men comprised 65.9% of the cohort. Sensitivity analyses evaluated cohort age, utility values, failure probabilities, and treatment costs. Data were derived from the Hip Improvement Project and the Hip and Knee Replacement Pilot databases in Alberta, the 2010 National Joint Replacement Registry of the Australian Orthopaedic Association, and the literature.
  
  
  RESULTS
  In the base case, THA was dominated by MoM HRA (incremental mean costs of -$583 and incremental mean QALYs of 0.079). In subgroup analyses, THA remained dominated when cohort age was 40 years instead of 50 years or when only men were assessed. THA dominated when the cohort age was 60 years or when only women were assessed. Results were sensitive to utilities, surgery costs, and MoM HRA revision and conversion probabilities. At a willingness-to-pay of Can $50,000/QALY, there was a 58% probability that MoM HRA is cost-effective.
  
  
  CONCLUSIONS
  The results show that, on average, MoM HRA was preferred to THA for younger and male patients, but THA is still a reasonable option if the patient or clinician prefers given the small absolute differences between the options and the confidence ellipses around the cost-effectiveness estimates.
authors.affiliation: Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada; Department of Health Technology & Services Research, University of Twente, Enschede, The Netherlands.
authors.forename: Sanne
authors.initials: S
authors.lastname: Heintzbergen
authors.forename: Nathalie A
authors.initials: NA
authors.lastname: Kulin
authors.forename: Maarten J
authors.initials: MJ
authors.lastname: Ijzerman
authors.forename: Lotte M G
authors.initials: LM
authors.lastname: Steuten
authors.forename: Jason
authors.initials: J
authors.lastname: Werle
authors.forename: Hoa
authors.initials: H
authors.lastname: Khong
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Marshall
mesh_terms: D000328:Adult; D000416:Alberta; D019644:Arthroplasty, Replacement, Hip / Q000191:economics*; D003365:Costs and Cost Analysis; D016208:Databases, Factual; D005260:Female; D017048:Health Care Costs; D006306:Health Surveys; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D015233:Models, Statistical; D009043:Motor Activity; D015207:Osteoarthritis, Hip / Q000601:surgery*; D011475:Prosthesis Failure; D019057:Quality-Adjusted Life Years
keywords: Birmingham; cost-utility; hip resurfacing; osteoarthritis; total hip replacement