Histology evaluation of efficacy of bevacizumab. (A) H & E and AB-PAS staining of the synovium and articular cartilage. The NC group exhibited the most severe degenerative changes and synovium hyperplasia while the bevacizumab group shows fewer cartilage degenerative changes and less synovium hyperplasia. Scale bar, 50 mm (in top panels), 100 mm (in middle and bottom panels). (B) Gross scores show that cartilage degeneration in the NC group was the most severe one among the four groups while the bevacizumab group exhibited the least degenerative changes, indicating that bevacizumab treatment was effective to prevent cartilage damage; n = 8 per group. *p < 0.05, bevacizumab group, SH group, TA group compared to the NC group. #p < 0.05, bevacizumab group compared to the SH group and TA group. (C) Mankin scores showed that the cartilage degeneration in the NC group was the most severe one among the four groups while the bevacizumab group showed the least degenerative changes, indicating that bevacizumab treatment reduced the extent of cartilage damage; n = 8 per group. *p < 0.05, bevacizumab group, SH group, TA group compared to the NC group, #p < 0.05, bevacizumab group compared to the SH group and TA group.