Arthroscopy is a rod-shaped optical instrument with a diameter of about 4 mm that is used to view the internal structure of a joint and is an endoscope for the treatment of joint disorders. This instrument has been used since 1970. The arthroscope is equipped with a lens at the end of a thin tube, which is inserted into the joint, and the internal structure of the joint is displayed on a monitor. As a result, the structures inside the joint can be directly observed. Arthroscopy is not only used for diagnosis of diseases, but has been widely used for treatment of joint diseases. Arthroscopic surgery is a minimally invasive procedure that was first performed on the knee joint, and later on the hip, shoulder, ankle, elbow, fingers and other small joints. Arthroscopy can see almost all parts of the joint, which is more comprehensive than cutting open the joint, and because the image is magnified, it is more accurate, and the incision is small, less traumatic, less scarring, faster recovery, and fewer complications. Arthroscopic surgery can often achieve immediate results in the diagnosis of difficult joint diseases and in the treatment of joint injuries that have plagued patients for many years. Advantages of arthroscopic surgery 1. small incision, aesthetic, can avoid late irritation caused by scarring on the joint surface and sports areas; 2. minimally invasive surgery, less painful, less postoperative reaction, easy for patients to accept; 3. early postoperative can move and use the limb, avoid long-term bedside complications, reduce nursing staff and costs; 4. relatively few complications; 5. basically does not affect the muscle around the joint The structure of the muscles around the joint is basically not affected, and functional exercises can be performed early after surgery to prevent disuse and complications caused by long-term fixation of the joint; 6, the intra-articular lesions can be observed and examined in a nearly physiological environment, which is known as “putting eyes and fingers into the joint”, and the dynamic examination of the joint can be carried out to improve the diagnostic ability. Certain diseases, such as synovial crease syndrome, are established only through arthroscopy; 7. Arthroscopy can perform surgeries that were difficult to complete with open surgery, such as meniscal suture, anterior and posterior cruciate ligament reconstruction of the knee, etc.