Arthroscopic treatment of post-traumatic knee chondral defects using microfractures and the Autologous Collagen-Induced Chondrogenesis (ACIC™) technique: a retrospective observational cohort study.

Abstract

This study aimed to evaluate return to sport and one-year clinical outcomes in young athletes with focal grade III-IV knee chondral lesions treated arthroscopically using the Autologous Collagen-Induced Chondrogenesis (ACIC™) technique, which combines microfractures with an atelocollagen scaffold stabilized by fibrin glue. A retrospective cohort study was conducted on all consecutive patients undergoing arthroscopic microfractures with ACIC™. Inclusion criteria comprised monofocal ICRS III-IV knee chondral defects ≥1 cm², young sports-active patients, and a minimum follow-up of one year. Patients with malalignment >5°, knee instability, inflammatory disease, BMI ≥30, or kissing lesions were excluded. Pain and function were assessed after injury and one year postoperatively. Sport level (Tegner Activity Scale) was compared before injury and at one year postoperatively. Four patients met the inclusion criteria. Lesions were located on the femoral condyle (n = 3) or tibial plateau (n = 1), with a mean defect area of 1.8 ± 1 cm². Three patients returned to their pre-injury level of sport at one year. No significant difference was observed between pre-injury and postoperative Tegner scores. Significant improvements were found in VAS pain (p = 0.004) and IKDC functional scores (p = 0.0009) after surgery. All patients reported to be highly satisfied with the surgery. Arthroscopic ACIC™ demonstrated significant pain reduction, improved knee function, and a high rate of return to pre-injury sport level at one-year follow-up in young athletes with focal high-grade knee chondral lesions. Larger studies with long-term follow-up are needed to confirm durability and characterize cartilage repair quality. III.