title: Femoral head diameter affects the revision rate in total hip arthroplasty: an analysis of 1,720 hip replacements with 9-21 years of follow-up.
abstract: BACKGROUND
  In a previous study concerning 1,660 ScanHip THAs that were followed for up to 12 years, the cumulative revision rate was not found to be dependent on whether a 22-mm or a 32-mm head size had been used. We have re-examined these patients to see whether a longer follow-up time (9-21 years) would disclose an effect of head size on the revision rate.
  
  
  METHODS
  We analyzed the cumulative revision rate for 1,720 Scan Hip arthroplasties with either 22-mm or 32-mm femoral heads. The patients were followed for 9-21 years.
  
  
  RESULTS
  Arthroplasties with 32-mm head had 2.8-times higher cumulative revision rate than those with a 22-mm head. Older age reduced the risk of revision while male sex increased the risk.
  
  
  CONCLUSIONS
  We found that head size affects revision risk, but that even in a reasonably large material a long follow-up time is required to disclose the effects of head size--and thus wear--on survival.
authors.affiliation: Department of Orthopaedics, Kaunas Medical University, Lithuania. sarunastarasevicius@gmail.com
authors.forename: Sarunas
authors.initials: S
authors.lastname: Tarasevicius
authors.forename: Uldis
authors.initials: U
authors.lastname: Kesteris
authors.forename: Otto
authors.initials: O
authors.lastname: Robertsson
authors.forename: Hans
authors.initials: H
authors.lastname: Wingstrand
mesh_terms: D000367:Age Factors; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000601:surgery; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D005260:Female; D005270:Femur Head; D005500:Follow-Up Studies; D006620:Hip Fractures / Q000601:surgery; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D012307:Risk Factors