Complications and Radiographic Outcomes of Tibial Tubercle Osteotomy at Minimum 5-Year Follow-up

Background: Tibial tubercle osteotomy (TTO) is a commonly utilized surgery in the treatment of patellofemoral instability and chondrosis. A number of case series studies have reported on the mid- and long-term outcomes with varying complication rates.Purpose: To report the incidence of major complications after TTO and the rate of progression of knee osteoarthritis at midterm follow-up.Study Design: Case series; Level of evidence, 4.Methods: All patients who underwent primary TTO between January 1, 2010 and December 31, 2015, and who had >= 5 years of clinical follow-up data were included. Patient demographics and clinical and radiographic outcomes were recorded. Risk factors for complications were identified using multivariate logistic regression analysis.Results: A total of 72 patients were included. The mean follow-up period was 104.8 months (range, 67-138 months). The overall complication rate was 38.9% (28/72 patients), and the incidence of major complications was 6.9%. Univariate logistic regression analysis revealed that patients with a history of smoking were more likely to experience a complication (odds ratio = 4.33 [95% CI, 1.29-14.53]; P = .02). Multivariate analysis with TTO as the main predictor indicated that complication rates were not affected by TTO procedure (TTO vs TTO+other), number of screws, or distalization. There was also no difference between anteromedialization and medialization TTO techniques. The rate of patients with Kellgren-Lawrence grade 3 to 4 increased from 12.0% preoperatively to 23.9% at the final follow-up. New osteophyte formation was detected in 5.8% of patients on anteroposterior radiographs and in 9.1% of patients on lateral radiographs.Conclusion: In the current study, TTO was found to have a major complication rate of 6.9% at midterm follow-up. Smoking was a risk factor for major complications. Only 11.9% of patients had progression in tibiofemoral osteoarthritis at midterm follow-up.