title: Risk factors for revision of primary total hip replacement: results from a national case-control study.
abstract: OBJECTIVE
  To study the risk factors for revision of primary total hip replacement (THR) in a US population-based sample.
  
  
  METHODS
  Using Medicare claims, we identified beneficiaries from 29 US states who underwent primary THR between July 1, 1995 and June 30, 1996, with followup through December 31, 2008. Potential cases had International Classification of Diseases, Ninth Revision, Clinical Modification codes indicating a revision THR. Each case was matched by state with 1 control THR recipient who was alive and unrevised when the case had a revision THR. We abstracted hospital records to document potential risk factors. We examined the associations between preoperative factors and revision risk using multivariate conditional logistic regression.
  
  
  RESULTS
  The analysis data set contained 719 of 836 case-control pairs with complete data for analysis variables. The factors associated with higher revision odds in multivariate models were age ≤75 years at primary surgery (odds ratio [OR] 1.52 [95% confidence interval (95% CI) 1.20-1.92]), height in the highest tertile (OR 1.40 [95% CI 1.06-1.85]), weight in the highest tertile (OR 1.66 [95% CI 1.24-2.22]), cemented femoral component (OR 1.44 [95% CI 1.10-1.87]), prior contralateral primary THR (OR 1.36 [95% CI 1.05-1.76]), other prior orthopedic surgery (OR 1.45 [95% CI 1.13-1.84]), and living with others (versus alone; OR 1.26 [95% CI 0.99-1.61]).
  
  
  CONCLUSIONS
  This first US population-based case-control study of risk factors for revision of primary THR showed that younger, taller, and heavier patients and those receiving a cemented femoral component had a greater likelihood of undergoing a revision THR over a 12-year followup period. Effects of age and body size on revision risk should be addressed by clinicians with patients considering primary THR.
authors.affiliation: Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. wright@hsph.harvard.edu
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Wright
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Katz
authors.forename: John A
authors.initials: JA
authors.lastname: Baron
authors.forename: R John
authors.initials: RJ
authors.lastname: Wright
authors.forename: Henrik
authors.initials: H
authors.lastname: Malchau
authors.forename: Nizar
authors.initials: N
authors.lastname: Mahomed
authors.forename: Julian J Z
authors.initials: JJ
authors.lastname: Prokopetz
authors.forename: Elena
authors.initials: E
authors.lastname: Losina
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000706:statistics & numerical data*; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D001843:Bone Cements / Q000627:therapeutic use; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D006278:Medicare; D016017:Odds Ratio; D011475:Prosthesis Failure; D012086:Reoperation / Q000706:statistics & numerical data*; D012307:Risk Factors; D014481:United States
chemical_list: D001843:Bone Cements