The most common condition that causes swelling and pain in the joints of the legs is synovitis, which causes swelling and pain in the joints due to the production of fluid in the joint cavity. If the amount of fluid in the joint is relatively small, oral non-steroidal anti-inflammatory and analgesic drugs, such as COX2 inhibitors, celecoxib, erliximab and other drugs to reduce the mobility of the joints, and the joints around the adjunctive hot packs, waxing, infrared and other physical therapy, the general symptoms can be relieved within 3 weeks. If the amount of fluid is large and the pain is severe, oral medication can be taken along with arthrocentesis to extract the fluid, intra-articular injection of glucocorticoids, and localized compression bandage, which can relieve the swelling and pain within 3 weeks.