The main purpose of intra-articular injection of sodium vitrate in the knee joint is to nourish the cartilage of the knee joint and improve the accumulation of fluid in the knee joint. Sodium vitrate has the ability to nourish cartilage and promote the absorption of fluid in the joint cavity, which can relieve the pain of osteoarthritis of the knee joint. Sodium vitrate helps to promote the improvement of the microenvironment of the knee joint and prevent the continued aggravation of synovitis or the continued production of fluid in the knee joint. Intra-articular injection of sodium vitreous acid in the knee joint cavity has the effect of increasing lubrication, reducing friction between cartilage and avoiding pain after walking or exercising, mainly for the treatment of arthritis and improvement of joint effusion.