Knee pain in young people after a sports sprain, pain in women going up and down stairs or squatting, knee pain and inconvenient walking in the elderly, all these knee problems are caused by damage to soft tissues such as cartilage and ligaments in the joint. In the past, it was difficult to correctly diagnose these problems, and the only way to treat them after a clear diagnosis was to operate on the knee, but incisional surgery is a big wound, painful for the patient, and takes months to restore knee function. Now there is a reliable treatment technique, arthroscopic surgery, that can avoid the need for incisional surgery. Arthroscopic surgery is a minimally invasive technique in the field of orthopedics, which has been used clinically in foreign countries since the 1970s and was introduced in China in the 1980s. When performing arthroscopic surgery, the surgeon makes two to three 4-6 mm long incisions around the corresponding joint under anesthesia, and puts an arthroscope thinner than the head of a chopstick into the joint through one of the incisions, which is connected to an extra-articular monitor through optical fibers, so that almost all parts of the joint can be seen on the monitor, which is more comprehensive than an incision. The doctor can make a clear diagnosis of the condition inside the joint. At the same time, a slim surgical instrument can be inserted through a separate incision to treat the lesions in the joint, such as removing swollen synovial membrane, removing bone fragments that affect joint movement, suturing torn meniscus, and reconstructing intra-articular ligaments. As a result, arthroscopic surgery does not require extensive incision and exposure of the joint, so it is naturally less invasive than incision surgery, with fewer complications and faster recovery. Moreover, due to the small incision, the postoperative scar is almost invisible, which eliminates the fear of postoperative scarring for many patients, especially female patients, and makes them more receptive to surgical treatment. Arthroscopy can be performed on a wide range of large joints such as the hip, knee, ankle, shoulder, elbow, wrist, and even finger joints. The most common indications for arthroscopic treatment are knee and shoulder joints, osteoarthritis, joint free bodies, meniscal injuries, and cruciate ligament injuries. In short, arthroscopic surgery can be used for both diagnosis and treatment; it can treat both chronic diseases such as arthritis and acute trauma such as fractures. President Clinton underwent an arthroscopic ACL reconstruction procedure. Minimally invasive arthroscopic surgery has become the method of choice for the treatment of joint disease today.