title: The survivorship and results of total knee replacements converted from unicompartmental knee replacements.
abstract: Unicompartmental knee replacements (UKR) converted to total knee replacements (TKR) have often been viewed with scepticism because of the perceived difficulty of revising a UKR to a TKR. We present the survivorship analysis of a 77 patient cohort as well as the current results of a 35 patient cohort. There were a total of 77 patients in the survivorship study with an average follow-up of 6.9 years and an average Bristol Knee Score of 78.5. Using Kaplan-Meier survivorship analysis, a 91% survivorship at 10 years was demonstrated. The average age at revision to TKR was 66.1 years. The average follow-up period was 10.5 years and a recent clinical and radiological review of the 35 living patients showed an average Bristol Knee Score of 78.2 with 16 excellent, 11 good, five fair and three failed.
  
  
  CONCLUSIONS
  The results of the UKRs have already shown it to be safe, reliable and repeatable. We believe that this study shows that revision of UKR to TKR is not technically difficult and that the results are comparable to the results of primary TKRs.
authors.affiliation: Avon orthopaedic centre, Southmead hospital, Bristol, UK. simonandti@telkomsa.net <simonandti@telkomsa.net>
authors.forename: Simon
authors.initials: S
authors.lastname: Johnson
authors.forename: Peter
authors.initials: P
authors.lastname: Jones
authors.forename: John H
authors.initials: JH
authors.lastname: Newman
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D007720:Knee Prosthesis; D008297:Male; D011475:Prosthesis Failure; D012086:Reoperation; D016896:Treatment Outcome