 Intra-articular injection of platelets are activated and undergo degranulation, releasing a range of growth factors, including transforming growth factor beta TGF-β, platelet-derived growth factor PDGF, insulin-like growth factor, vascular endothelial growth factors, epidermal growth factors and basic fibroblast growth factor 2. These growth factors are thought to activate a variety of signaling pathways, which promote healing of bone and soft tissue.Also,some minimally invasive therapeutic options have been effective in pain relieve in KA, such as ultrasound-guided saphenous nerve block . 