title: Comparative study of computer-assisted total knee arthroplasty after opening wedge osteotomy versus after unicompartmental arthroplasty.
abstract: OBJECTIVE
  The role of high tibial osteotomy (HTO) is being questioned by the use of unicompartmental knee arthroplasty (UKA) in the treatment of medial compartment femorotibial osteoarthritis. Our aim was to compare the outcomes of revision HTO or UKA to a total knee arthroplasty (TKA) using computer-assisted surgery in matched groups of patients.
  
  
  METHODS
  We conducted a retrospective study to compare the clinical and radiological outcome of patients who underwent revision of a HTO to a TKA (group 1) with those who underwent revision of a medial UKA to a TKA (group 2). All revision procedures were performed using computer-assisted surgery. We extracted these groups of patients from our database. They were matched by age, gender, body mass index, follow-up and pre-operative functional score. The outcomes included the Knee Society Scores (KSS), radiological outcomes and the rate of further revision.
  
  
  RESULTS
  There were 20 knees in 20 patients in each group. The mean follow-up was 4.1 years (2 to 18.7). The mean total KSS at last follow-up was 185.7 (standard deviation (sd) 5) in group 1 compared with 176.5 (sd 11) for group 2 (p = 0.003). The mean hip-knee-ankle angle was 180.2° (sd 3.2°) in group 1 and 179.0° (sd 2.2°) in group 2. No revision was required.
  
  
  CONCLUSIONS
  We found that good functional and radiological outcomes followed revision of both HTO and UKA to TKA. Revision of HTO showed significantly better functional outcomes. These results need to be further investigated by a prospective randomised controlled trial involving a larger group of patients. Cite this article: Bone Joint J 2016;98-B:1620-4.
authors.affiliation: Grenoble South Teaching Hospital, Avenue de Kimberley, BP 338, 38434, Échirolles, France.
authors.forename: R
authors.initials: R
authors.lastname: Pailhé
authors.affiliation: Grenoble South Teaching Hospital, Avenue de Kimberley, BP 338, 38434, Échirolles, France.
authors.forename: J
authors.initials: J
authors.lastname: Cognault
authors.affiliation: Grenoble South Teaching Hospital, Avenue de Kimberley, BP 338, 38434, Échirolles, France.
authors.forename: J
authors.initials: J
authors.lastname: Massfelder
authors.affiliation: The Royal Orthopaedic Hospital, Birmingham, UK.
authors.forename: A
authors.initials: A
authors.lastname: Sharma
authors.affiliation: Grenoble South Teaching Hospital, Avenue de Kimberley, BP 338, 38434, Échirolles, France.
authors.forename: R-C
authors.initials: RC
authors.lastname: Rouchy
authors.affiliation: Grenoble South Teaching Hospital, Avenue de Kimberley, BP 338, 38434, Échirolles, France.
authors.forename: B
authors.initials: B
authors.lastname: Rubens-Duval
authors.affiliation: Grenoble South Teaching Hospital, Avenue de Kimberley, BP 338, 38434, Échirolles, France.
authors.forename: D
authors.initials: D
authors.lastname: Saragaglia
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010027:Osteotomy / Q000009:adverse effects / Q000379:methods*; D011859:Radiography; D020127:Recovery of Function; D012086:Reoperation / Q000009:adverse effects / Q000379:methods; D012189:Retrospective Studies; D012720:Severity of Illness Index; D025321:Surgery, Computer-Assisted / Q000009:adverse effects / Q000379:methods*; D013977:Tibia / Q000601:surgery; D016896:Treatment Outcome
keywords: Computer-assisted surgery; High tibial osteotomy; Unicompartmental knee arthroplasty