High tibial valgus osteotomy for medial gonarthrosis: a 10- to 21-year study.

This retrospective study reviewed the long-term experience with high tibial osteotomy and determined which factors influence the results. Between 1980 and 1989, 120 closing wedge high tibial osteotomies for varus gonarthrosis were performed in 102 patients. Twenty-nine knees were excluded because the patients died (17 knees), were bedridden (7 knees), or lost to follow-up (5 knees). Thirty of the remaining 91 knees had a conversion to total knee replacement (TKR) after 11 years on average, leaving 61 knees with a high tibial osteotomy available for clinical and radiographic evaluation at an average follow-up of 15 years (range: 10-21 years). Of the 91 knees, excellent/good results were found in 49% and fair/poor in 51%. Anatomical femorotibial angle in the 61 knees at follow-up averaged 4.7 degrees +/- 5 degrees of valgus (range: 3 degrees varus to 23 degrees valgus). Alignment obtained at consolidation changed with varus recurrence at follow-up in 14% of 61 knees and did not correlate with the clinical results. Twelve (19%) knees showed a patella baja (Caton ratio <0.6) at follow-up, which correlated with patients immobilized postoperatively by a cylinder cast (P=.04). A valgus alignment at consolidation between 8 degrees and 15 degrees, good muscle strength, and male gender correlated with better results (P<.05). Survivorship analysis, considering an unsatisfactory result or revision to TKR as the endpoint, was 96% at 5 years, 88% at 7 years, 78% at 10 years, and 57% at 15 years. High tibial osteotomy provides symptomatic relief for approximately 10 years, but is unlikely to provide permanent relief.