OBJECTIVETo observe the long-term outcome of high tibial osteotomy (HTO) in treating medial compartment osteoarthrosis of knees.

METHODSA retrospective study was carried out on 194 patients (215 knees) treated with HTO for medial compartment osteoarthritis at the Orthopaedic Hospital of Kiel University between 1985 and 1996.

RESULTSOne hundred and sixty-one knees (144 patients) were followed up for 1.5-12 years with an average of 7.5 years and their data were reviewed. The proportion of excellent outcome were 97.3%, 93.6% and 78.2% two, five and over five years after HTO, respectively. The revision rate of total knee arthroplasty (TKA) was 11.8% (19 knees retreated with TKA for HTO failure). The survivorship analysis of the 19 knees retreated with TKA showed an expected survival rate of 98.7%, 95.0% and 84.1% 2, 5 and 10 years after HTO, respectively. There were 5.6% complications (12/161), including five superficial wound infections, one deep infection, five delayed bone healing, and one peroneal nerve palsy. Fifty patients (54 knees) missed follow-up, among them 10 patients (11 knees) died.

CONCLUSIONSHTO is an effective method in treating medial compartment osteoarthritis with a varus knee. Appropriate overcorrection of femorotibial alignment is the key for the success of the operation. But as the long-term effect is concerned, there is a trend of deterioration and some of the patients may have a second operation of revision with TKA.