Eight-Year Clinical, Radiological, and Survival Outcomes of Knee Chondral Lesions Treated With High-Density Autologous Chondrocyte Implantation

Abstract

Background Articular cartilage lesions of the knee are difficult to manage due to their limited healing capacity. High-Density Autologous Chondrocyte Implantation (HD-ACI) has emerged as a promising treatment for symptom relief and functional recovery. Methods This retrospective study included 124 patients (88 men, 36 women; median age 35.5 years) with symptomatic chondral lesions of the knee treated with HD-ACI between 2010 and 2016. Patients were followed for up to 8 years. Visual Analogue Scale (VAS) for pain, International Knee Documentation Committee (IKDC) scores for knee function, and MOCART scores based on MRI evaluations of cartilage repair tissue were used for clinical assessment. Results Pain significantly decreased from a mean VAS of 6.7 to 1.1 at 8 years (p<0.001). IKDC scores improved from 39.4 to 81.6 (p<0.001), being higher than the minimal clinically important difference (MCID). MOCART scores progressively increased over time. Knee mobility in both extension and flexion showed statistically significant improvement. Adverse events were mild and infrequent. Kaplan–Meier analysis showed an implant survival of 97.5% and an overall treatment survival of 92.6% at 8 years. Conclusions HD-ACI is a safe and effective treatment for knee cartilage lesions, with long-term improvements in pain, joint function, confirmed clinically and radiologically.