title: The effect of patient age at intervention on risk of implant revision after total replacement of the hip or knee: a population-based cohort study.
abstract: Total joint replacements for end-stage osteoarthritis of the hip and knee are cost-effective and demonstrate significant clinical improvement. However, robust population based lifetime-risk data for implant revision are not available to aid patient decision making, which is a particular problem in young patient groups deciding on best-timing for surgery.
  
  
  
  We did implant survival analysis on all patients within the Clinical Practice Research Datalink who had undergone total hip replacement or total knee replacement. These data were adjusted for all-cause mortality with data from the Office for National Statistics and used to generate lifetime risks of revision surgery based on increasing age at the time of primary surgery.
  
  
  
  We identified 63 158 patients who had undergone total hip replacement and 54 276 who had total knee replacement between Jan 1, 1991, and Aug 10, 2011, and followed up these patients to a maximum of 20 years. For total hip replacement, 10-year implant survival rate was 95·6% (95% CI 95·3-95·9) and 20-year rate was 85·0% (83·2-86·6). For total knee replacement, 10-year implant survival rate was 96·1% (95·8-96·4), and 20-year implant survival rate was 89·7% (87·5-91·5). The lifetime risk of requiring revision surgery in patients who had total hip replacement or total knee replacement over the age of 70 years was about 5% with no difference between sexes. For those who had surgery younger than 70 years, however, the lifetime risk of revision increased for younger patients, up to 35% (95% CI 30·9-39·1) for men in their early 50s, with large differences seen between male and female patients (15% lower for women in same age group). The median time to revision for patients who had surgery younger than age 60 was 4·4 years.
  
  
  
  Our study used novel methodology to investigate and offer new insight into the importance of young age and risk of revision after total hip or knee replacement. Our evidence challenges the increasing trend for more total hip replacements and total knee replacements to be done in the younger patient group, and these data should be offered to patients as part of the shared decision making process.
  
  
  
  Oxford Musculoskeletal Biomedical Research Unit, National Institute for Health Research.
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK.
authors.forename: Lee E
authors.initials: LE
authors.lastname: Bayliss
authors.affiliation: NIHR CLAHRC Wessex Methodological Hub, University of Southampton, Southampton, UK.
authors.forename: David
authors.initials: D
authors.lastname: Culliford
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK.
authors.forename: A Paul
authors.initials: AP
authors.lastname: Monk
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK.
authors.forename: Sion
authors.initials: S
authors.lastname: Glyn-Jones
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK; GREMPAL Research Group, Idiap Jordi Gol and CIBERFes, Universitat Autonoma de Barcelona and Instituto de Salud Carlos III, Barcelona, Spain; MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Prieto-Alhambra
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK; MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Judge
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK; MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Cooper
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Carr
authors.affiliation: Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, University of Oxford, Oxford, UK; MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.
authors.forename: Nigel K
authors.initials: NK
authors.lastname: Arden
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Beard
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science, NIHR Biomedical Research Unit, University of Oxford, Oxford, UK. Electronic address: andrew.price@ndorms.ox.ac.uk.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Price
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000706:statistics & numerical data; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D003362:Cost-Benefit Analysis; D003657:Decision Making; D005260:Female; D006615:Hip / Q000601:surgery*; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000453:epidemiology / Q000401:mortality / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000453:epidemiology / Q000401:mortality / Q000601:surgery; D011475:Prosthesis Failure; D012086:Reoperation / Q000009:adverse effects* / Q000706:statistics & numerical data*; D012307:Risk Factors; D016019:Survival Analysis