title: Total knee replacement in previous recipients of fresh osteochondral allograft transplants.
abstract: BACKGROUND
  Fresh osteochondral allograft transplantation is a treatment option for young patients with osteochondral lesions of the knee. The present study evaluated the surgical complexity of, and the prevalence of complications related to, total knee arthroplasty in patients who had had a previous osteochondral graft transplantation.
  
  
  METHODS
  A retrospective analysis was performed on thirty-three consecutive patients (thirty-five knees) who underwent total knee arthroplasty from 1974 to 2000 after having had a previous transplantation of a fresh osteochondral allograft into the same knee. The mean duration of follow-up was ninety-two months. Perioperative data were analyzed with regard to etiology, preoperative impairment, intraoperative technical complications, early and late postoperative complications, and postoperative functional and subjective outcomes. The Knee Society clinical rating system was used for clinical evaluation beginning in 1990.
  
  
  RESULTS
  Four knees required additional techniques for exposure. Three knees required stemmed components, one knee required a tibial augment, and two knees required morselized grafts. The mean Knee Society objective score (available for eighteen knees) improved from 34.7 preoperatively to 87.9 at the time of the latest follow-up, and the mean Knee Society function score improved from 45 to 82. The mean range of motion of all knees improved from 85 degrees to 105 degrees . Six of the thirty-five knees underwent revision total knee arthroplasty because of aseptic loosening, with two knees being revised within two years after the index total knee arthroplasty.
  
  
  CONCLUSIONS
  Total knee arthroplasty after previous fresh osteochondral allograft transplantation provides improvements in knee function and range of motion, with manageable technical difficulties. Compared with routine total knee arthroplasty, an increased rate of early revision can be expected.
authors.affiliation: Orthopaedic Division, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada. moragim@gmail.com
authors.forename: Guy
authors.initials: G
authors.lastname: Morag
authors.forename: Anna
authors.initials: A
authors.lastname: Kulidjian
authors.forename: Paul
authors.initials: P
authors.lastname: Zalzal
authors.forename: Nadav
authors.initials: N
authors.lastname: Shasha
authors.forename: Allan E
authors.initials: AE
authors.lastname: Gross
authors.forename: David
authors.initials: D
authors.lastname: Backstein
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D019902:Chondrocytes / Q000637:transplantation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010011:Osteocytes / Q000637:transplantation; D016059:Range of Motion, Articular / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology; D012086:Reoperation; D012189:Retrospective Studies; D016896:Treatment Outcome