Seven knees with medial osteoarthrosis, in which tibial osteotomy was performed with hemicallotasis over a year previously, were evaluated clinically and radiographically. The average age of patients was 63 years and average follow-up period was 14 months. Femorotibial angle changed from 181 to 167 degrees. JOA knee score improved to 93 postoperatively from 59 points. Hemicallotasis is a method for correcting varus deformity of the proximal tibia. In this method, however, upper displacement of the fibular head occurs and that is a unresolved problem.
