Artificial total knee replacement surgery has become a common clinical procedure to address severe knee pathologies, mainly for those with severe knee pain, instability, deformity, and severe limitations in activities of daily living, which are ineffective or not significant with conservative treatment. The common diseases are as follows. 1, osteoarthritis Osteoarthritis (OA), also known as osteoarthrosis, degenerative joint disease, hypertrophic arthritis, is a common chronic joint disease. Most commonly seen in the elderly, more women than men. 2, rheumatoid arthritis rheumatoid arthritis is an autoimmune disease, the cause is unknown. It is a common and persistent chronic arthritis, the most commonly invaded parts of the small joints of the limbs, can cause swelling, pain and dysfunction of the joints throughout the body, is one of the major disabling diseases. There are about 4 million patients in China, with an incidence of 0.32-0.34%. Rheumatoid arthritis is most common in women, with a male to female ratio of about 1:3. The age of onset of rheumatoid arthritis is mostly between 20 and 40 years old. The onset of the disease is slow, and most patients have a few weeks to months of fatigue, weight loss, poor appetite, low fever and numbness, tingling and other prodromal symptoms of the hands and feet. Traumatic arthritis Traumatic arthritis is also known as traumatic arthritis, injury arthritis. Traumatic arthritis is very common in clinical practice, mainly caused by intra-articular fracture or trauma, traumatic arthritis mainly manifests as knee pain. In the early stage, it is a sore or dull pain in the joint, followed by a friction-like pain in the joint, which is aggravated by exercise and relieved by rest. The knee joint is swollen due to synovial hypertrophy or joint effusion, and the swelling increases after exertion and gradually subsides after a longer period of rest. Patients with traumatic arthritis often have more severe sequelae and eruptions, such as persistent pain, progressive deformity, adhesions inside and outside the joint, poor mobility, and simple medication is no longer effective, so surgery can be considered. 4. Systemic lupus erythematosus arthritis (SLE) is a chronic disease that can involve many organ systems, such as the skin, nerves and plasma membranes. The etiology is unclear, and it is mostly thought to be an autoimmune disease. The disease is more prevalent in women, 5-10 times higher than in men. The age of onset is 2 to 90 years, but the most frequent is between 20 and 40 years. The high incidence in women shows the role of certain genetic factors. The majority of SLE patients have involvement of the hand, wrist, knee, ankle and elbow joints. The prominent features of arthritis in this disease are redness, swelling, heat, pain and stiffness of the joints, and deformity of large joints rarely occurs. 5. Psoriatic arthritis, etc. In fact, not all patients suffering from the above diseases must undergo artificial total knee replacement surgery. Patients who choose surgical treatment must meet the following 3 criteria: (1) There are X-ray changes of knee destruction. (2) There is persistent pain of moderate to severe severity. (3) There is no substantial improvement with long-term conservative treatment.