Hypertrophic chondrocytes in cartilage repair tissue of rabbit knee joint. Microphotograph showing collagen type × immunostained sections. (A,B) Cartilage repair tissue of osteochondral defect evaluated 16 weeks post-injury. Boxed area in (A) indicates the region shown in (B). (C,D) Normal articular cartilage. Boxed area in (C) indicates the region shown in (D). It is obvious that the chondrocytes undergo abnormal hypertrophic differentiation in cartilage repair tissue. Note the sites of abnormal hypertrophic chondrocytes (arrows). Scale bars: 50 μm (A,C); 20 μm (B,D).
Zhang et al. Arthritis Research & Therapy 2012 14:221 doi:10.1186/ar4025