Autologous Matrix Induced Chondrogenesis (AMIC) is a well-established treatment for full-thickness cartilage defects. The purpose of this study was to evaluate the long term clinical outcomes following repair, via AMIC procedure, of chondral defects of the knee.
A multi-site prospective registry recorded demographic data and outcomes for patients treated for repair of chondral defects. In total 131 patients were included in the study. Lysholm, KOOS and VAS-pain were used for outcome analysis. The average age of patients was 36.6±11.7 years. The mean body weight was 80.0±16.8 kg, with a mean height 176.3 ± 7.9 cm, and the mean defect size 3.3±1.8 cm2. Defects were classified as grade III / IV according to ICRS classification. A repeated measures ANOVA was used to compare outcomes across all time points.
The median follow-up time for the patients in this cohort was 4.56 ± 2.92 years. Significant improvement (p<0.001) of all scores was observed at 1-2 years after AMIC and improved values were notable up to 7 years postoperatively. The mean preoperative Lysholm score was 46.9 (± 19.7). At the 1-2 year follow-up, a significant increase of Lysholm score mean values was noted (83.1 ± 14.0) with maintenance of the favorable outcome during follow up at 7 years: (78.6 ± 17.1). Similarly, The KOOS score also showed a significant improvement of the postoperative values compared to the preoperative data. The mean preoperative VAS was 5.7 ± 1.8 and this had significantly decreased to. 2.5 ± 2.1 at the 7 years follow up. Age, gender and defect size did not have a significant effect on the outcomes.
AMIC is an effective method of treating chondral defects of the knee and leads to reliably favorable results up to 7 years post-operatively.