Arthroscopic second-generation autologous chondrocyte implantation compared with microfracture for chondral lesions of the knee: Prospective nonrandomized study at 5 years

Background: Various approaches have been proposed to treat articular cartilage lesions, which are plagued by inherent limited healing potential. Purpose: To compare the clinical outcome of patients treated with second-generation autologous chondrocyte implantation implants with those treated with the microfracture repair technique at 5-year follow-up. Study Design: Cohort study; Level of evidence, 2. Methods: Eighty active patients (mean age, 29.8 years) and grade III to IV cartilage lesions of the femoral condyles or trochlea were treated with arthroscopic second-generation autologous chondrocyte implantation Hyalograft C or microfracture (40 patients per group). Patients achieved a minimum 5-year follow-up and were prospectively evaluated. Results: Both groups showed statistically significant improvement of all clinical scores from preoperative interval to 5-year follow-up. There was a significant improvement for the International Knee Documentation Committee subjective score from preoperative to 5-year follow-up (Wilcoxon test, P