Arthroscopic microfracture vs. arthroscopic autologous matrix-induced chondrogenesis for the treatment of articular cartilage defects of the talus

Purpose Microfracture is an established method to treat osteochondral defects of the talus. The value of the addition of an acellular matrix is still under debate. This study compared the results of arthroscopic microfracture vs. arthroscopic autologous matrix-induced chondrogenesis using a collagen I/III matrix (AMIC) in the management of articular cartilage defects of the talus. Methods Patients with a minimum follow-up of 5 years after arthroscopic management for an articular cartilage defect of the talus with either microfracture alone or an additional acellular matrix were matched according to age, sex and BMI. The Hannover Scoring System for the ankle (HSS) and a Visual analog scale (VAS) for pain, function and satisfaction were used to evaluate the clinical outcome. Postoperative MRI was used to assess cartilage repair tissue based on the degree of defect repair and filling of the defect, integration to border zone, surface of the repair tissue, structure of the repair tissue, and subchondral bone alterations. Results Thirty-two patients (16 microfracture, 16 AMIC) were included. No significant between-group differences were observed in demographic data and preoperative score values. Both groups showed statistically significant improvement when comparing the pre- and postoperative score values. No statistically significant differences were identified between the median values of the groups with the HSS (microfracture: 82 (range 71-96) points; AMIC 88 (range 40-98) points). Accordingly, no significant differences were observed for the VAS pain (microfracture: 0.95 (range 0-3.8); AMIC: 1.0 (range 0-8.5)), VAS function (microfracture: 8.4 (range 3.5-10); AMIC: 9.0 (range 1.5-10)) and VAS satisfaction (microfracture: 8.9 (range 2.8-10); AMIC: 9.45 (range 1.5-10)). MRI showed regeneration of tissue in the treated area without differences between the two groups. Conclusion Good clinical results were observed for arthroscopic microfracture with or without an additional acellular collagen I/III matrix in the treatment for articular cartilage defects of the talus. It appears that for defects as treated in this study, it is not worthwhile adding the collagen I/III matrix to the microfractures.