Background: The purpose of this retrospective study was to assess the long-term results after the treatment of medial compartment gonarthrosis with a proximal tibial osteotomy to determine whether various clinical and radiographic factors relate to the outcome.
Methods: From 1972 to 1990, seventy-six valgus-producing high tibial osteotomies were performed in sixty-six patients with medial compartment gonarthrosis. Stabilization was achieved with use of a plate on the lateral side of the proximal part of the tibia and a figure-of-eight wire on the medial side. The mean age of the patients at the time of surgery was sixty-nine years, and the mean duration of follow-up was 10.8 years. The factors that were analyzed included postoperative valgus alignment; the age, gender, and weight of the patient; preoperative Ahlbäck radiographic grade; adverse events; Workers' Compensation status; and public liability. Survivorship outcome end points were conversion to arthroplasty, a Hospital for Special Surgery knee score of <70 points, and patient dissatisfaction with the procedure.
Results: Ten-year survival, according to the life-table method, was 74%, 70%, and 65% with conversion to arthroplasty, a Hospital for Special Surgery knee score of <70 points, and patient dissatisfaction, respectively, as the end points. Radiographic valgus alignment that ranged between 8° and 16° at one year after the osteotomy had the most significant positive effect on survivorship for all end points (p < 0.01) compared with the other parameters. Complications occurred in sixteen (21%) of the seventy-six procedures, and they had a significant effect on survival, with all three end points (p < 0.05).
Conclusions: We found that survival at ten years was 90% (95% confidence interval, 80% to 99%) when the radiographic valgus angle at one year was between 8° and 16° with arthroplasty as the end point. We believe that there is a role for tibial osteotomy, as an alternative to total knee arthroplasty, in patients who are less than sixty years old.
Level of Evidence: Therapeutic study, Level III-2 (retrospective cohort study). See Instructions to Authors for a complete description of levels of evidence.