title: Survivorship of second-generation metal-on-metal primary total hip replacement.
abstract: BACKGROUND
  Second generation metal-on-metal total hip replacements (THR) were introduced in the late 1980s and various studies reported conflicting data on their outcome.
  
  
  METHODS
  Implant survival of 1,270 second-generation 28 mm metal-on-metal primary THR in 1,121 patients followed prospectively at a mean of 6.8 years postoperatively was evaluated retrospectively. The probability of survival at 10 years was estimated using the method of Kaplan and Meier, and relative risk factors including age, gender, BMI, type of implant fixation and component size were calculated using the Cox proportional-hazards model.
  
  
  RESULTS
  Sixty-three (5%) THRs were revised, these being 28 hips for aseptic loosening and 35 for reasons other than aseptic loosening. The probability of survival at 10 years, with revision for any reason as the endpoint, was 0.90 (95% confidence interval (CI) 0.86-0.94) for the THR as a whole, 0.91 (95% CI 0.87-0.95) for the cup, and 0.96 (95% CI 0.94-0.98) for the stem. No demographic factors or covariates were found to significantly affect the implant survivorship.
  
  
  CONCLUSIONS
  As there was no superior probability of survival, and there have been concerns on putative local and systemic toxicity of metal debris, the use of second-generation metal-on-metal articulations for primary THR remains moot.
authors.affiliation: Schulthess Clinic, Zurich, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Neuerburg
authors.forename: F
authors.initials: F
authors.lastname: Impellizzeri
authors.forename: J
authors.initials: J
authors.lastname: Goldhahn
authors.forename: Ph
authors.initials: P
authors.lastname: Frey
authors.forename: F D
authors.initials: FD
authors.lastname: Naal
authors.forename: M
authors.initials: M
authors.lastname: von Knoch
authors.forename: M
authors.initials: M
authors.lastname: Leunig
authors.forename: F
authors.initials: F
authors.lastname: von Knoch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery*; D016016:Proportional Hazards Models; D011475:Prosthesis Failure / Q000209:etiology; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014800:Vitallium
chemical_list: D014800:Vitallium