Autologous matrix induced chondrogenesis (AMIC) aided reconstruction of osteochondral lesions of the talus - Five year follow-up

M. Wiewiorski, A. Barg, V. Valderrabano

Introduction: Autologous Matrix Induced Chondrogenesis (AMIC) for surgical treatment of osteochondral lesions of the talus (OCLT) has shown excellent clinical and radiological results at short term follow up two years after surgery. However, no mid-term follow up data is available.

Aim: 1. To evaluate the clinical outcome after AMIC-aided reconstruction of osteochondral lesions of the talus at a minimum follow up time of five years. 2. To evaluate the morphology and quality of the regenerated cartilage by magnetic
resonance imaging (MRI) at on at a minimum follow up time of five years.

Methods: Seventeen patients prospectively underwent surgery receiving a AMIC-aided repair of OCLT consisting of debridement, autologous grafting, and sealing of the defect with a collagen scaffold (Chondro-Gide, Geistlich Surgery, Wolhusen, Switzerland). Clinical and radiological assessment was performed before and after a minimum of 60 months after surgery (average 78 months, range, 60-120). Clinical examination included the American Orthopaedic Foot & Ankle Society (AOFAS) ankle score and the Visual Analogue Scale (VAS). Radiological imaging consisted of MRI. The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was applied.

Results: The AOFAS ankle score improved significantly from a mean of 60 points preoperatively (range, 17-79) to 91 points (range, 70-100) postoperatively (p< 0.01). The preoperative pain score averaged a VAS of 5 (range, 2-8), improving to an average of 1.1 (range 0-8) (p< 0.01). The MOCART score for cartilage repair tissue on postoperative MRI averaged 71 points (range, 50-90).

Conclusion: The AMIC-procedure is safe for the treatment of OCLT with overall good clinical and magnetic resonance imaging results at five years follow up.