title: Outcome of total knee arthroplasty after high tibial osteotomy: does malalignment jeopardize the results when using a posterior-stabilized arthroplasty?
abstract: BACKGROUND
  The controversy regarding the outcome of total knee arthroplasties after high tibial osteotomy may relate to malalignment secondary to overcorrection after high tibial osteotomy (HTO) [1, 2] and to the type of arthroplasty itself (posterior-stabilized arthroplasty or posterior cruciate ligament-retaining prosthesis).
  
  
  OBJECTIVE
  We asked two questions: (1) Would a posterior-stabilized arthroplasty provide sufficient constrain and improve pain and function in patients with severe malalignment due to a previous HTO? (2) Will malalignment of the previous HTO jeopardize the long-term results of a total knee reconstruction with a posterior-stabilized implant?
  
  
  METHODS
  We retrospectively reviewed 25 posterior-stabilized TKAs in 25 patients with severe valgus deformity after HTO (ranging from 10° to 20° of valgus) and compared the results with a series of matched 25 posterior-stabilized TKAs in 25 patients with normocorrection after HTO ranging from 5° of valgus to 5° of varus. Clinical, operative, and radiographic data were reviewed. Minimum follow-up was 10 years after the arthroplasty (average, 15 years; range, 10-20 years).
  
  
  RESULTS
  All the knees had standard posterior-stabilized total knee arthroplasty implants. Patients with an overcorrected HTO were more likely to require a soft tissue release to balance the knee. However, Average Knee Society and Function Score improved, respectively, from 48 to 85 and from 50 to 90 points in the severely overcorrected group, versus, respectively, 50 to 89 and 52 to 97 in the normocorrected group, but the range of mobility was superior for patients with normal alignment. Fifteen-year survivorship after the arthroplasty comparison showed no significant difference between the two groups (one revision in each group).
  
  
  CONCLUSIONS
  Patients with an overcorrected HTO are more likely to require a soft tissue release to balance the knee. However, both groups show improvements in function and pain. With a posterior-stabilized arthroplasty, the degree of deformity has no impact on the longevity of the TKA.
authors.affiliation: Hospital Henri Mondor, Avenue du Marechal de Lattre de Tassigny, 94000 Creteil, France ; University Paris East, 61 Avenue du Général de Gaulle, 94000 Creteil, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Hernigou
authors.affiliation: Hospital Henri Mondor, Avenue du Marechal de Lattre de Tassigny, 94000 Creteil, France ; University Paris East, 61 Avenue du Général de Gaulle, 94000 Creteil, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Duffiet
authors.affiliation: Hospital Henri Mondor, Avenue du Marechal de Lattre de Tassigny, 94000 Creteil, France ; University Paris East, 61 Avenue du Général de Gaulle, 94000 Creteil, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Julian
authors.affiliation: Hospital Henri Mondor, Avenue du Marechal de Lattre de Tassigny, 94000 Creteil, France ; University Paris East, 61 Avenue du Général de Gaulle, 94000 Creteil, France.
authors.forename: Issac
authors.initials: I
authors.lastname: Guissou
authors.affiliation: Hospital Henri Mondor, Avenue du Marechal de Lattre de Tassigny, 94000 Creteil, France ; University Paris East, 61 Avenue du Général de Gaulle, 94000 Creteil, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Poignard
authors.affiliation: Hospital Henri Mondor, Avenue du Marechal de Lattre de Tassigny, 94000 Creteil, France ; University Paris East, 61 Avenue du Général de Gaulle, 94000 Creteil, France.
authors.forename: Charles Henri
authors.initials: CH
authors.lastname: Flouzat-Lachaniette
keywords: high tibial osteotomy; posterior-stabilized arthroplasty; total knee arthroplasty