title: Isolated metal-backed patellar component revision following total knee arthroplasty.
abstract: BACKGROUND
  Twenty-two consecutive revisions for failed metal-backed patellar components following total knee arthroplasty in 17 patients were retrospectively reviewed. All had similar total condylar knee prosthesis inserted with retention of the posterior cruciate ligament and resurfacing of the patella with a metal-backed component. There were 3 male and 14 female patients.
  
  
  RESULTS
  The mean time to failure of the patellar component was 60 months (range 26 to 93 months). The majority of patients presented with metallic crepitus (86.4%) and knee pain (72.7%). At surgery, full thickness polyethylene wear exposing the metal-backing was present in 81.8% with surface damage of the femoral components present in 40.9%. All 22 cases underwent successful isolated patellar component revision with all polyethylene patellar components.
  
  
  CONCLUSIONS
  Resurfacing of the patella in total knee arthroplasty with metal-backed patellar components carries a significant risk of early failure and the use of these components is no longer practised at our institution.
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Singapore.
authors.forename: W H
authors.initials: WH
authors.lastname: Chan
authors.forename: S J
authors.initials: SJ
authors.lastname: Yeo
authors.forename: B P
authors.initials: BP
authors.lastname: Lee
authors.forename: B K
authors.initials: BK
authors.lastname: Tay
authors.forename: S K
authors.initials: SK
authors.lastname: Tan
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008670:Metals; D008875:Middle Aged; D010003:Osteoarthritis / Q000601:surgery*; D010329:Patella / Q000601:surgery*; D011095:Polyethylenes; D011475:Prosthesis Failure; D012086:Reoperation
chemical_list: D008670:Metals; D011095:Polyethylenes