Rheumatoid arthritis is a chronic systemic autoimmune disease characterized by synovitis of the joints. The persistent and recurrent attacks of synovitis can lead to destruction of cartilage and bone in the joints, resulting in joint dysfunction. Vasculitis lesions involve all organs of the body, so the disease is also known as rheumatoid disease. The cause of rheumatoid arthritis is not yet known. It is an autoimmune inflammatory disease with chronic, symmetric, multisynovial arthritis and extra-articular lesions as the main clinical manifestations. The disease occurs in the small joints of the hands, wrists and feet, with recurrent attacks and symmetrical distribution. From the perspective of pathological changes, rheumatoid arthritis is a widespread inflammatory disease involving mainly the synovial membrane (but also the articular cartilage, bone tissue, joint ligaments and muscle keys), followed by the plasma membrane, heart, lung and eye and other connective tissues. The rheumatoid arthritis can affect all age groups, mostly between the ages of 16-55, more women than men, about 2.5:1. The onset is mostly gradual, patients are often accompanied by general malaise and low-grade fever, as well as loss of appetite, weight loss, sweating and joint pain and other prodromal symptoms. Most rheumatoid arthritis is symmetric polyarthritis, rarely starting in one joint. The small joints of both hands (the metacarpophalangeal joints of the 2-5 fingers and the interproximal joints are the most frequently affected), knees, wrists and feet are most often involved. The joints begin with pain and stiffness in the early stages, followed by swelling, fluid accumulation and increased local temperature. The joint stiffness is most pronounced after rising in the morning and decreases with activity, called morning stiffness. Subsequently, due to the swelling and pain of the joint and the limitation of movement, the stiffness and atrophy of the muscles near the joint become more pronounced. Even if the acute inflammation dissipates, the periarticular tissues become stiff due to the proliferation of fibrous tissue in the joint. As the lesion develops, the joint eventually becomes stiff and deformed, with the knee, elbow, fingers, and wrist fixed in flexion. The fingers often become semi-dislocated laterally at the metacarpophalangeal joint, forming a characteristic ulnar deviation deformity, which is called “blowing hand”. About 10%-30% of patients have subcutaneous nodules, hard as rubber, at the joint’s prominence, such as the eminence of the upper limb, the wrist and the ankle of the lower limb. Subcutaneous nodules are not easily absorbed, and the presence of subcutaneous nodules often indicates severe active disease. In addition, a small number of patients (about 10%) have lymph nodes and splenomegaly during the active phase of the disease. Ocular sclerositis and keratoconjunctivitis may be present. Cardiac involvement with clinical manifestations is less common and is found in about 35% according to autopsy, mainly affecting the mitral valve and causing valvular lesions. Patients with lung disease present in various forms, pleurisy, diffuse interstitial lung fibrosis, rheumatoid pneumoconiosis. Peripheral neuropathy and chronic calf ulcers, amyloidosis, etc. can also occasionally be found. 3, diagnosis Late rheumatoid patients, because there are multi-joint lesions and typical deformities, so the diagnosis is not difficult. However, in the early stage of the disease and a few cases of joint involvement, there are often difficulties in diagnosis. At present, for the diagnosis of rheumatoid arthritis, different countries have different criteria. 1958, the American College of Rheumatology proposed a modified diagnostic criteria, many countries have adopted this standard.