title: Simultaneous revision and contralateral primary total knee arthroplasty.
abstract: BACKGROUND
  There is controversy regarding whether simultaneous or staged bilateral total knee arthroplasty should be performed in patients with bilateral gonarthrosis. In addition, revision total knee arthroplasties have been less successful than primary arthroplasties. The purpose of this study was to evaluate the results of simultaneous revision and contralateral primary total knee arthroplasties performed during the same setting.
  
  
  METHODS
  The study cohort included 150 knees in seventy-five patients who had undergone revision arthroplasty because of aseptic failure of a total knee arthroplasty and a contralateral primary arthroplasty for severe gonarthrosis under the same anesthetic. The study group was compared with a control group of sixty patients who had severe arthritis in one knee and had undergone unilateral revision total knee arthroplasty on the contralateral side. The duration of follow-up averaged five years in the group treated with the simultaneous arthroplasties and eight years in the control group. Clinical and radiographic results were evaluated with the Knee Society rating system.
  
  
  RESULTS
  In the study group, the average knee score improved by 48 points on the side of the primary arthroplasty and by 37 points on the side of the revision. At the last follow-up visit, most (sixty-five) of the seventy-five patients stated that the knee with the revision felt better than the knee with the simultaneously performed primary arthroplasty. In the control group, the average knee score improved by 30 points on the side of the revision arthroplasty. However, forty-five of the sixty patients had a primary total knee arthroplasty on the contralateral side within two years after the index revision arthroplasty; by four years, all sixty patients had undergone a contralateral primary arthroplasty.
  
  
  CONCLUSIONS
  We found a favorable outcome in patients who had undergone simultaneous revision and contralateral primary total knee arthroplasties. Despite a lower mean knee score and less motion, most patients seemed to prefer the knee with the revision arthroplasty to the knee with the primary procedure. These results suggest that this combined procedure is a safe and favorable alternative to a staged procedure consisting of revision and subsequent contralateral primary total knee arthroplasty.
authors.affiliation: Pennsylvania Hospital, Philadelphia 19107, USA. hbezwada@yahoo.com
authors.forename: Hari P
authors.initials: HP
authors.lastname: Bezwada
authors.forename: David G
authors.initials: DG
authors.lastname: Nazarian
authors.forename: Robert E
authors.initials: RE
authors.lastname: Booth
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D010147:Pain Measurement; D011475:Prosthesis Failure; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology; D012086:Reoperation / Q000009:adverse effects / Q000379:methods; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome