Figure 7.

Histology evaluation after IA injection of the etoricoxib-loaded NPs. A. OA was induced by ACLT and IA injections were performed at 3, 6, and 9 weeks. Rats were sacrificed for analysis at 12 weeks after OA induction. B. Gross images of the femoral condyle. C. Safranin-O/Fast green staining of the joints. D. OARSI scores of the four groups at indicated time points. (**P<0.01, ***P<0.001). E. Hematoxylin and eosin staining of the synovium. In addition to ETX NPs group, the other groups showed a slight increase in the synovial lining cell layer, a slight increase in the density of synovial matrix, and inflammatory infiltration of small follicular like lymphocytes. F. Synovitis score. (**P<0.01, ***P<0.001).