Fig. 4From: In vivo animal study and clinical outcomes of autologous atelocollagen-induced chondrogenesis for osteochondral lesion treatmentMicroscopic view of repaired tissue 12Â weeks after operation (hematoxylin/eosin). Cartilage defects in groups 1 and 4 were not adequately filled with repaired tissue. Fibrocartilage tissue is also found in repaired tissue instead of normal hyaline cartilage. Defect completely filled with repaired tissue in groups 2 and 3, and composed of normal hyaline cartilage. a, b Group 1. c, d Group 2. e, f Group 3. g, h Group 4. *right panel is a magnified view of the yellow box in the left panel. HC hyaline cartilage, FC fibrocartilageBack to article page