Autologous Chondrocyte Implantation for Talar Osteochondral Lesions: Comparison Between 5-Year Follow-Up Magnetic Resonance Imaging Findings and 7-Year Follow-Up Clinical Results

Autologous chondrocyte implantation (ACI) is an established surgical procedure that has provided satisfactory results. The aim of the present study was to correlate the clinical outcomes of a series of 20 patients treated by ACI at a 7-year follow-up examination with the magnetic resonance imaging (MRI) T2-mapping 5-year follow-up findings. We evaluated 20 patients using the American Orthopaedic Foot and Ankle Society (AOFAS) score preoperatively and the established follow-up protocol until 87.2 ± 14.5 months. MRI T2-mapping sequences were acquired at the 5-year follow-up examination. At the MRI examination (60 ± 12 months), the mean AOFAS score improved from 58.7 ± 15.7 to 83.9 ± 18.4. At the final follow-up examination at 87.2 ± 14.5 months, the AOFAS score was 90.9 ± 12.7 (p = .0005). Those patients who experienced an improvement between 5 and 7 years after surgery had a significant greater percentage of T2-map value of 35 to 45 ms (hyaline cartilage) compared with those patients who did not improve (p = .038). MRI T2 mapping was shown to be a valuable tool capable of predicting reproducible clinical outcomes after ACI even 7 years after surgery. The quality of the regenerated tissue and the degree of defect filling became statistically significant to the clinical results at the final follow-up examination.