BACKGROUND Varisation osteotomies on the distal femur are an established treatment method for valgus osteoarthritis of the knee in younger patients. Osteotomy can be done in a lateral open-wedge or medial closed-wedge manner. METHODS We retrospectively studied 14 patients treated by the lateral open-wedge technique, fixed with the Tomofix plate, with a mean duration of follow-up of 45 ± 3.4 months. RESULTS We observed often delayed osteotomy healing after 3, 6 and 12 months, no secondary dislocations, and frequent troublesome irritation due to the plate being on the iliotibial band. However, outcome was satisfactory once the osteotomy healed and the plate was removed. CONCLUSIONS Based on the often slow healing of the osteotomy and frequent irritation due to the plate, this procedure has been abandoned by the authors, and the medial closing-wedge osteotomy adopted as the alternative treatment.