title: Functional outcome after acetabular revision with roof reinforcement rings.
abstract: OBJECTIVE
  To evaluate the role for potential predictors of functional outcome after acetabular arthroplasty and to assess the results of revision with the use of a roof reinforcement ring.
  
  
  METHODS
  A retrospective case series.
  
  
  METHODS
  A tertiary-care referral centre.
  
  
  METHODS
  Twenty-four patients (average age 72.7 years) who had undergone acetabular revision with a roof reinforcement ring were followed up for an average of 2.8 years.
  
  
  METHODS
  Revision acetabular arthroplasty was performed using either the Mueller or Burch Schneider roof reinforcement ring, bone grafting and a cemented polyethylene cup.
  
  
  METHODS
  A modified Harris hip score (range of motion omitted), the SF-36 health survey and the Western Ontario McMaster (WOMAC) osteoarthritis index measured outcome. Multivariate analysis was used to determine the effects of certain clinical factors (age, sex, time to revision from previous hip operation and number of previous revisions) on outcome.
  
  
  RESULTS
  Patients reported disability both on hip-specific and general health measures. The time to revision from previous operation positively correlated with SF-36 mental component scores (p = 0.003), WOMAC function (p = 0.04) and WOMAC pain (p = 0.03). Age, gender and number of past revisions did not affect outcome.
  
  
  CONCLUSIONS
  Patients who undergo acetabular revision with a roof ring will continue to have some disability in the first 3 years after the procedure. A greater time between the previous operation and the revision operation is associated with a better outcome. Patients' expectations of postoperative results should be realistic in the face of a challenging reconstructive procedure.
authors.affiliation: Department of Surgery, St. Michael's Hospital, University of Toronto, Ont.
authors.forename: R
authors.initials: R
authors.lastname: Jain
authors.forename: E H
authors.initials: EH
authors.lastname: Schemitsch
authors.forename: J P
authors.initials: JP
authors.lastname: Waddell
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D016025:Bone Transplantation; D005260:Female; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000601:surgery*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies