Importance of sports in cartilage regeneration after autologous chondrocyte implantation: a prospective study with a 3-year follow-up.

Background: There have been no data in the literature reporting the influence of sports on the outcome of autologous chondrocyte implantation in chondral defects of the knee. Hypothesis: Sports can improve the result of autologous chondrocyte implantation in postoperative follow-up. Study Design: Cohort study; Level of evidence, 2. Methods: Between 1997 and 2003, 118 patients with symptomatic isolated chondral lesions of the knee underwent autologous chondrocyte implantation. According to the sports activity level before the start of symptoms, patients were assigned to 2 groups: group II with no or rare sports involvement (1-3 times/month); group I with regular (1-3 times/week) or competitive sports (4-7 times/week). All patients underwent clinical and magnetic resonance imaging evaluation preoperative and 6, 18, and 36 months after autologous chondrocyte implantation. Results: Group I patients showed significantly better results (<.01) in the International Cartilage Repair Society and Cincinnati scores than group II patients. Preoperative evaluation revealed no correlation between the sports activity levels and the clinical scores (P >.05). However, from the sixth month on, correlation was statistically significant, increasing from 6 to 18 months, and from 18 to 36 months postoperatively. Conclusion: Physical training improves long-term results after autologous chondrocyte implantation of the knee and should be carried out for at least 2 years after surgery.