There are three main types of injections for the treatment of arthritis: first, hormonal drugs, such as compound betamethasone injection and tretinoin acetate injection, which are injected intra-articularly into the knee joint to relieve inflammation in the joint, reduce inflammatory irritation and reduce inflammatory edema. Secondly, sodium vitrate injection, which is mainly used for joint lubrication after intra-articular injection of the knee joint, is usually injected into the joint after the inflammation in the joint has been significantly controlled and the pain and unfavorable activity symptoms have been effectively relieved. The third is for local osteophyte degeneration, producing sterile inflammatory lesions of the injection, such as prednisolone acetate injection, lidocaine hydrochloride injection, these two drugs mixed and then local closed injection, can effectively reduce the local pain, which is usually called closed needle, only to relieve symptoms, for some obvious damage to the lesion, it is not recommended to apply.