Matrix-assisted autologous chondrocyte transplantation for cartilage regeneration in osteoarthritic knees: Results and failures at midterm follow-up

Background: Young patients with osteoarthritic knees are a challenging population because of a combination of high functional demands and limited indication for joint replacement. Purpose: To analyze the potential of the cartilage regenerative approach by documenting the results and failures of matrixassisted autologous chondrocyte transplantation (MACT) at midterm follow-up. Study Design: Case series; Level of evidence, 4. Methods: Forty-four patients affected by cartilage lesions in osteoarthritic knees underwent MACT as a salvage procedure. The mean age at surgery was 42 years (range, 20-58 years), and the average defect size was 4 cm² (range, 1.5-9 cm²). Patients were prospectively evaluated with the subjective International Knee Documentation Committee (IKDC), EuroQol visual analog scale (EQ-VAS), and Tegner scores preoperatively; at 1, 2, and 5 years; and at a final assessment at 9 years' mean follow-up. Adverse events and failures were also reported. Results: A statistically significant improvement was observed in all scores from the initial evaluation to the final follow-up. The mean ± standard deviation IKDC subjective score improved from 38.0 ± 15.8 to 67.0 ± 18.3 at 2 years (P