A systematic review on Autologous Matrix Induced Chondrogenesis (AMIC) for chondral knee defects

Background

Chondral defects of the knee can be identified in up to 60% of patients undergoing knee arthroscopy. The use of Autologous Matrix Induced Chondrogenesis (AMIC), which combines subchondral microfracture with a collagen membrane, has been increasingly used to treat these defects.

Aims

This review assesses the clinical, functional, and radiological outcomes of patients undergoing the AMIC procedure and reports any associated complications.

Methods

Studies with a minimum of 10 patients and fulfilled at least a 12-month follow up period with more than 70% follow up rate were included. Methodological quality was assessed using MINORS (Methodological Index for Non-Randomised Studies) criteria. The meta-analysis compared Lysholm, VAS (Visual Analog Scale), IKDC (International Knee Documentation Committee), KOOS (Knee Injury and Osteoarthritis Outcome Score) Pain, and Tegner clinical outcome measures at baseline and follow up.

Results

18 studies (n = 490 patients) were included. The mean age was 35.2 [SD = 5.0] years and the mean defect size was 3.47 [SD = 0.96] cm². There was a clinically significant improvement in Lysholm, IKDC, and KOOS scores of 30.36 [95% CI (25.80, 34.93)], 34.05 [95% CI (4.16, 43.95)], and 30.63 [95% CI (24.78, 36.47)] respectively; and reduction in VAS pain score of −4.10 [95%CI (−4.50, −3.71) at follow up. Improvement in Tegner score at follow up was not statistically significant: 0.21 [95% CI (−0.88, 1.30)],(p > 0.05).

Conclusion

AMIC is a safe, effective, and reliable technique to treat knee chondral defects which can provide significant clinical, functional, and radiological improvements to patients.