Stable clinical long term results after AMIC in the aligned knee

Area of Science:

• Orthopedic Surgery
• Regenerative Medicine
• Biomaterials Science

Background:

• Full-thickness chondral and osteochondral defects in the femoral condyle or patella are common knee injuries.
• Current treatments often involve joint replacement, which may not be ideal for young, active patients.
• Autologous matrix-induced chondrogenesis (AMIC) is a technique for cartilage repair.

Purpose of the Study:

• To report the long-term follow-up results of patients treated with AMIC for knee cartilage defects.
• To evaluate the effectiveness of AMIC when combined with correction of lower limb malalignment or patellar tracking.
• To assess the durability of AMIC outcomes over an average of 9 years.

Main Methods:

• A cohort of 33 patients (34 knees) with chondral or osteochondral defects underwent AMIC.
• Patients were categorized into patellar chondral lesions (cP), femoral condyle chondral lesions (cF), and osteochondritis dissecans (ocF).
• Associated procedures like patellar realignment or osteotomy were performed as needed; clinical outcomes were assessed using Lysholm and VAS scores.

Main Results:

• After a mean follow-up of 9.3 years, 79% of patients completed the assessment.
• Significant improvements in Lysholm (85 ± 13) and VAS pain (1.9 ± 1.6) scores were observed compared to preoperative values (Lysholm 56 ± 19, VAS 5.8 ± 2.4).
• Outcomes remained stable from the 2-year mark, with particularly favorable results in aligned knees and those with corrected malalignment.

Conclusions:

• AMIC demonstrates durable, long-term efficacy for knee cartilage defects, particularly in aligned knees.
• Combining AMIC with corrective procedures for lower limb malalignment and patellar tracking maintains favorable outcomes.
• AMIC is a valuable joint-preserving option for young adults, potentially delaying or avoiding knee arthroplasty.