Psychological guidance Explain the importance of surgery to the patient, inform the advantages of minimally invasive surgery, introduce the method of anesthesia, position, and the way of surgery so that the patient and his family can be fully prepared. Evaluate the general condition of the patient before the operation, and find out whether the patient has any past history, previous use of medication and drug allergy history, and secondly, find out the patient’s physical condition when he was admitted to the hospital, and whether he has any other diseases. Improve the preoperative examinations including blood routine, urine routine, blood biochemistry and immunity examination. Blood coagulation and coagulation function examination, electrocardiogram, chest X-ray, X-ray examination and so on. 4. Others Before operation, patients should be instructed to eat a high-calorie, high-protein, high-vitamin diet to increase the supply of nutrients. Closely observe all vital signs before operation, female patients should pay attention to whether they are menstruating. Preparation of limbs Patients with knee joint lesions have joint swelling and pain before surgery. After admission to the hospital, patients should rest in bed and minimize the weight-bearing activities of the joints in order to eliminate swelling and achieve better surgical results. Hospitalization that is to begin to guide the patient for quadriceps functional exercise, 2 times a day straight leg raising exercise, and let the patient learn quadriceps isometric contraction exercises, in order to complete the postoperative rehabilitation program to lay a good foundation. Skin preparation 1, arthroscopic surgery on the surgical area of the skin requirements are relatively strict, preoperative skin protection is extremely important. 2.Patients should be told to avoid scratching and touching the affected limbs. If the skin appears itchy, red and swollen phenomenon immediately notify the doctor. Specific practices 1, skin preparation Remove microorganisms from the skin to reduce infection and create good skin conditions for surgery. Prepare the skin in to the upper 1/3 of the thigh, down to the toes. Be careful not to scratch the skin. 2. Inform the patient to fast from 10:00 p.m. on the day before the operation and to abstain from water until 6 hours after the operation. If it is difficult for the patient to fall asleep before surgery, sedative can be given as prescribed by the doctor. 3.Special preoperative exercises, preoperative should be taught how to use the commode, how to urinate in bed.