title: Good functional results following high tibial opening-wedge osteotomy of knees with medial osteoarthritis: A prospective study with a mean of 8.3years of follow-up.
abstract: BACKGROUND
  To report time dependent functional improvement and predictive risk factors for failure when the load in varus knees with medial osteoarthritis is shifted from the medial to the lateral knee compartment.
  
  
  METHODS
  Forty-nine consecutive patients (52 knees), mean age 47 (31-64) years, underwent a high tibial opening-wedge valgus osteotomy stabilized with a Puddu plate and bone grafting. The patients were evaluated with the Knee Injury and Osteoarthritis Outcome Score (KOOS) preoperatively and at three and six months, one, two, five and 10years postoperatively with a mean follow-up time of 8.3years (2.0-10.6).
  
  
  RESULTS
  Mean angular correction was 8.0° (four to 12). The five subscores of KOOS increased significantly during the first year by 40-131% from preoperative values, the good results remaining throughout the 10-year follow-up for those with a surviving osteotomy. The outcome was related to the grade of preoperative osteoarthritis. Seven knees were converted to total knee arthroplasty (TKA) mean 6.2years (two to nine) post-operatively, and had a lower KOOS preoperatively than those of surviving osteotomies. The osteotomy survival rate at five years was 94% and at 10years 83%. Patients with KOOS subscore quality of life (QoL) <44 at the two-year follow-up had a 11.7 times higher risk for later TKA than those with QoL ≥44 (P=0.017).
  
  
  CONCLUSIONS
  High tibial opening-wedge osteotomy for medial knee osteoarthritis resulted in good functional recovery after one year and favorable mid-term results. It may be a good treatment option for middle-aged patients with varus knees and medial osteoarthritis in order to prevent or postpone TKA.
authors.affiliation: Martina Hansens Hospital, Box 823, N-1306 Sandvika, Norway. Electronic address: arne.ekeland@mhh.no.
authors.forename: Arne
authors.initials: A
authors.lastname: Ekeland
authors.affiliation: Martina Hansens Hospital, Box 823, N-1306 Sandvika, Norway.
authors.forename: Tor Kjetil
authors.initials: TK
authors.lastname: Nerhus
authors.affiliation: Lovisenberg Diaconal Hospital, Lovisenberggata 17, N-0456 Oslo, Norway.
authors.forename: Sigbjørn
authors.initials: S
authors.lastname: Dimmen
authors.affiliation: Martina Hansens Hospital, Box 823, N-1306 Sandvika, Norway.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Thornes
authors.affiliation: Martina Hansens Hospital, Box 823, N-1306 Sandvika, Norway.
authors.forename: Stig
authors.initials: S
authors.lastname: Heir
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010027:Osteotomy / Q000379:methods*; D011446:Prospective Studies; D020127:Recovery of Function; D012307:Risk Factors
keywords: Bone transplantation; KOOS; Opening-wedge; Osteotomy survival; Tibial osteotomy; Varus knee