I. Indications 1. Purpose of surgery: firstly, to relieve pain, and secondly, to improve the stability and mobility of the knee joint. The indications for surgery are determined according to the patient’s condition, age, occupation, weight, and mental status. 2. Specific indications: (1) Primary osteoarthritis, rheumatoid arthritis, traumatic arthritis, hemophilic arthritis and some other non-septic arthropathies (including tuberculosis) in the later stages. (2) Patients with rheumatoid arthritis who have impaired mobility due to pain and deformity, in order to improve their quality of life. (3) Bone tumors of the distal femur or proximal tibia, if the limb can be preserved, artificial knee arthroplasty with special prosthesis can be performed after resection of the tumor segment. Preoperative preparation 1. Routine preoperative examination: pay attention to blood pressure and blood sugar, the condition of the deep veins of the lower extremities, and the presence of local or systemic infections (such as periodontitis, tinea pedis and other chronic inflammatory diseases, etc.). Find out whether the patient is taking some kind of medicine for a long time, such as Rivaroxaban to stop the operation for more than 5 days. General examination: make preliminary evaluation of knee joint appearance, swelling or joint effusion, skin temperature, muscle atrophy, tenderness, quadriceps and N cord muscle strength, joint mobility and limb alignment (knee joint internal and external rotation) by conventional means such as visualization (looking), touch, movement and measurement. Measurement of the knee joint: Measurement is of great importance in the evaluation of the knee joint. Measurements of the knee joint should include multiple parameters such as limb alignment, Q-angle, joint mobility (ROM), patellar position and medial and lateral mobility in both knees, and the differences in measurements of the left and right knee joints are often meaningful. Ligament stability test: The Lachman test is the most important test to check the function of the cruciate ligament and is very meaningful in evaluating the function of the cruciate ligament. The lateral compression test, on the other hand, is the primary means of checking the function of the medial and lateral collateral ligaments. The above tests should enable a determination of the stability of the knee joint. Routine laboratory tests: blood, urine, stool, blood group, liver and kidney function, HIV, HAV, HCV, syphilis antibodies, blood glucose, electrolytes, sedimentation and c-reactive protein are important to rule out infectious arthritis and to provide reference for postoperative follow-up. Auxiliary examinations: X-ray examination of the knee joint: anteroposterior film of the whole length of the lower limbs in standing position; ultrasound of the heart and blood vessels of both lower limbs; arthrocentesis, routine and bacteriological examination of joint fluid, CT, MRI, isotope bone scan, etc. if necessary. 2.Pre-operative guidance Pre-operative talk and guidance for the patient is an important part of eliminating psychological fears and cooperating with surgery and post-operative rehabilitation. Pre-operative deep breathing, coughing and bed urination and defecation are important to avoid post-operative pneumonia, urinary retention and constipation; quadriceps muscle strength training and ROM training methods; discontinuation of certain drugs that may affect the surgery; treatment of diseases that may lead to infection such as tinea pedis. Pre-operative antibiotic application: Prevention of surgical infection is of great importance in TKA surgery. Intravenous administration during the induction of anesthesia is the best time to administer antibiotics prophylactically. In cases of bilateral simultaneous TKA surgery, an additional antibiotic should be administered before the start of surgery on the second side.