title: Closing-wedge high tibial osteotomy: survival and risk factor analysis at long-term follow up.
abstract: BACKGROUND
  Closing-wedge high tibial osteotomy (HTO) is successful for the treatment of medial osteoarthritis with varus malalignment. Preoperative risk factors for HTO failure are still controversial. The aim of this study was to elucidate the outcome and assess the influence of risk factors on long term HTO survival.
  
  
  METHODS
  199 patients were retrospectively studied with a mean follow-up period of 9.6 years after HTO. HTO failure was defined as the need for conversion to TKA. Survival was analyzed with the Kaplan-Meier method. Knee function was evaluated by the Hospital for Special Surgery (HSS) score. HTO-associated complications were also assessed. Univariate, multivariate, and logistic regression analysis were performed to evaluate the influence of age, gender, BMI, preoperative Kellgren-Lawrence osteoarthritis grade, and varus angle on HTO failure.
  
  
  RESULTS
  39 complications were recorded. Thus far, 36 HTOs were converted to TKA. The survival of HTO was 84% after 9.6 years. Knee function was considered excellent or good in 64% of patients. A significant preoperative risk factor for HTO failure was osteoarthritis, Kellgren-Lawrence grade >2.
  
  
  CONCLUSIONS
  HTO provides good clinical results in long-term follow-up. Preoperative osteoarthritis Kellgren-Lawrence grade >2 is a significant predictive risk factor for HTO failure. Results of HTO may be improved by careful patient selection. Complications associated with HTO should not be underestimated.
authors.affiliation: Department of Orthopaedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043 Marburg, Germany. efet@med.uni-marburg.de
authors.forename: Turgay
authors.initials: T
authors.lastname: Efe
authors.forename: Gafar
authors.initials: G
authors.lastname: Ahmed
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Heyse
authors.forename: Ulrich
authors.initials: U
authors.lastname: Boudriot
authors.forename: Nina
authors.initials: N
authors.lastname: Timmesfeld
authors.forename: Susanne
authors.initials: S
authors.lastname: Fuchs-Winkelmann
authors.forename: Bernd
authors.initials: B
authors.lastname: Ishaque
authors.forename: Stefan
authors.initials: S
authors.lastname: Lakemeier
authors.forename: Markus D
authors.initials: MD
authors.lastname: Schofer
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010027:Osteotomy / Q000009:adverse effects* / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D013977:Tibia / Q000601:surgery*; D017211:Treatment Failure; D016896:Treatment Outcome