Col II-CS-HA cartilage biomimetic matrix gel provides a new treatment option for huge cartilage defects – a case report

Introduction: Articular cartilage injuries constitute a predominant musculoskeletal disease in athletic populations. These lesions frequently precipitate the progressive degeneration, culminating in premature career termination and increased functional impairment. However, current treatment methods for cartilage injury are not entirely satisfactory, especially for large full-thickness cartilage defects. Presentation of case: A 13-year-old male adolescent with documented high-intensity athletic engagement (training >15 hours/week) presented a huge exercise-induced full-thickness cartilage defect (6 cm 2 ) over the sulcus of the trochlea. The patient underwent arthroscopic implantation of our laboratory-engineered type II collagen-chondroitin sulfate-hyaluronic acid (Col II-CS-HA) biomimetic matrix gel, a tri-component hydrogel designed to mimic native cartilage extracellular matrix composition. Serial evaluations over 12 months postoperatively demonstrated significant improvement in both structural regeneration (7 T MRI T2-mapping showing >95% defect filling with hyaline-like tissue) and functional recovery (IKDC score increased from 31 to 100), with no adverse events reported. Notably, the patient resumed pre-injury sports activities at 9-month follow-up. Discussion: Current treatment strategies for cartilage defects, including microfracture and autologous chondrocyte implantation, demonstrate limited long-term efficacy for large full-thickness cartilage defects (>2 cm 2 ). The avascular nature of articular cartilage limits its inherent regenerative capacity. Tissue engineering approaches have emerged as promising solutions by providing biomimetic scaffolds and recruiting endogenous chondroprogenitor cells for hyaline-like cartilage regeneration. Conclusion: The case we present demonstrates the effectiveness of this Col II-CS-HA cartilage biomimetic matrix gel, which is expected to become a new effective solution for huge cartilage defects in future clinical practice.