Figure 3.

Histological morphology of femoral articular cartilage with Safranin-O staining in SED (a), LIR (b), MIR (c), and HIR (d) groups. Although grossly normal histological characteristics of cartilage sections were observed in SED, LIR, and MIR groups, the increased staining for Safranin-O was clearly found in LIR and MIR groups in comparison with SED group. In contrast, osteoarthritic histological changes of surface irregularities, cell cloning, and moderate reduction in the safranin-O staining were found in HIR group.