H&E staining showed that, compared with the CIA group, PFD significantly alleviated synovial hyperplasia and inflammatory cell infiltration in the knee joints (p < 0.05) (Figures 1D,F); immunohistochemistry also indicated that PFD effectively reduced VEGF protein expression in CIA joints (Figure 1E). The gene discussed is VEGFA; the disease is polyostotic fibrous dysplasia.