In arthritis of the varus knee, a high tibial osteotomy (HTO) redistributes load from the diseased medial compartment to the unaffected lateral compartment.

We report the outcome of 36 patients (33 men and three women) with 42 varus, arthritic knees who underwent HTO and dynamic correction using a Garches external fixator until they felt that normal alignment had been restored. The mean age of the patients was 54.11 years (34 to 68). Normal alignment was achieved at a mean 5.5 weeks (3 to 10) post-operatively. Radiographs, gait analysis and visual analogue scores for pain were measured pre- and post-operatively, at one year and at medium-term follow-up (mean six years; 2 to 10). Failure was defined as conversion to knee arthroplasty.

Pre-operative gait analysis divided the 42 knees into two equal groups with high (17 patients) or low (19 patients) adductor moments. After correction, a statistically significant (p < 0.001, t-test,) change in adductor moment was achieved and maintained in both groups, with a rate of failure of three knees (7.1%), and 89% (95% confidence interval (CI) 84.9 to 94.7) survivorship at medium-term follow-up.

At final follow-up, after a mean of 15.9 years (12 to 20), there was a survivorship of 59% (95% CI 59.6 to 68.9) irrespective of adductor moment group, with a mean time to conversion to knee arthroplasty of 9.5 years (3 to 18; 95% confidence interval ± 2.5).

HTO remains a useful option in the medium-term for the treatment of medial compartment osteoarthritis of the knee but does not last in the long-term.

Cite this article: Bone Joint J 2016;98-B:601–7.

We report the long-term outcome of 33 patients (37 knees) who underwent proximal tibial open-wedge osteotomy with hemicallotasis (HCO) for medial osteoarthritis of the knee between 1995 and 2000. Among these, 29 patients with unilateral HCO were enrolled and 19 were available for review at a mean of 14.2 years (10 to 15.7) post-operatively. For these 19 patients, the mean Hospital for Special Surgery knee score was 60 (57 to 62) pre-operatively and 85 (82 to 87) at final follow-up (p < 0.001; paired t-test). The femorotibial angle and tibial inclination angle (IA) were measured at short-term follow-up, one to four years post-operatively, and showed no significant subsequent changes. The clinical scores and radiological measurements showed little change over time. One patient required conversion to total knee replacement during this time. These results suggest that the coronal angle achieved at operation is maintained at long-term follow up after HCO without alteration of the IA, providing a good long-term clinical outcome.

Cite this article: Bone Joint J 2014;96-B:467–72.