During a 10-year period, 314 tibial osteotomies were performed for medial gonarthrosis. At follow-up after 10-19 years, 62 knees had been revised by arthroplasty (52 cases) or reosteotomy (10 cases). The revision rate was 54/170 in undercorrected knees and 8/144 in knees with normalization or overcorrection of the hip-knee-ankle angle. Our results confirm that tibial osteotomy for gonarthrosis requires proper indications and precise surgery. Perhaps, given another 10 years, our osteotomies will have outlived contemporary arthroplasties.