Repair of osteochondral lesions in the knee by chondrocyte implantation using the MACI® technique

PURPOSE: Matrix-associated autologous chondrocyte implantation (MACI(®)) is an innovative therapeutic option for the treatment of chondral and osteochondral lesions of the knee. METHODS: Fifty-three patients (54 knees) with MRI-documented osteochondral lesions were treated with MACI(®). A clinical assessment was performed using VAS score, Lysholm score, and Tegner activity level after an average follow-up of 27 months (SD: 2.3). MRI scans were performed 12 and 24 months after surgery. Seventeen patients were reevaluated after an average time of 59 months (SD: 6.7) after surgery. RESULTS: Two years after transplantation, Lysholm score increased from a preoperative mean value of 70 (SD: 13.4) to 95 (SD: 6.4); the average VAS score decreased from a preoperative value of 5.2 (SD: 2.9) to 1.9 (SD: 2.1). The difference with respect to Tegner activity level did not prove to be significant. At 1 year, MRI scans documented a completely repaired defect with slight subchondral bone abnormality in 38 cases (70%). Satisfying outcomes were confirmed on 17 patients who were reevaluated 5 years after surgery. At 60 months, MRI scans showed complete integration with the surrounding native cartilage without any sign of detachment or bone marrow edema in 15 cases (88%). CONCLUSION: The MACI(®) technique is a safe and clinically effective procedure, which has been proven to be valuable in treating osteochondral defects even over the long term.