1, the application of arthroscopy In the past, any surgery involving joints often required a large incision and a long hospital stay, placing a heavy burden on the patient. In recent years, with the development of arthroscopic surgery technology, it can make the surgery safer and also shorten the hospital stay, even difficult surgery can be done under the arthroscope. Compared with traditional surgery methods, arthroscopic surgery has very little chance of infection and is less likely to damage the normal tissues of the joints, resulting in less postoperative pain, shorter hospital stays, and less burden on the patient because the joints are always flushed with saline. In addition, from the aesthetic point of view, the scar of the postoperative incision is, in most cases, very small. At present, arthroscopy has been applied to knee, shoulder, ankle, elbow, hip and wrist joints to perform surgery. 2.Surgery under arthroscopic surveillance Two to three small incisions are made on the surface of the skin around the joint, then saline is injected into the joint, and an arthroscope consisting of a fiber optic cable and a high performance camera is inserted into the joint to directly observe the site of surgery and repair the damage, and to clean out the free body and damaged tissue in the joint. By magnifying the image through the TV, meniscal damage, cruciate ligament damage, and wear and tear of articular cartilage in the knee joint, as well as rotator cuff damage, habitual dislocation of the shoulder joint, and glenoid labral damage in the shoulder joint can be observed in detail and operated on directly. Small incision (left side), arthroscopic image (right side) Different from the known gastroscope, the tip is a rod-shaped metal speculum to allow insertion into the joint and direct observation.