An arthroscope is a rod-shaped optical instrument with a diameter of about 5mm to observe the internal structure of a joint, and is an endoscope used by physicians to diagnose and treat joint diseases. This instrument has been widely 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 internal structure of the joint can be directly observed. Arthroscopic surgery is performed by cutting several “chopstick”-sized or smaller holes (5 to 10 millimeters) in the skin, inserting a camera and surgical instruments into the joint, and operating them under the supervision of a monitor to diagnose and treat various joint diseases. What can arthroscopic surgery do? Currently, arthroscopic surgery can be performed on the following joints: knee, shoulder, ankle, elbow, wrist, jaw, hip, metacarpophalangeal joints, and even thoracic and lumbar spine joints. Advantages of arthroscopic surgery? 1.Small incision without infection, minimal skin scarring. 2.Surgical trauma is small, safe and repeatable, without affecting the joints for other surgeries in the future. 3.Arthroscopic surgery can treat many kinds of diseases at the same time, such as knee surgery can be carried out at the same time joint cleaning surgery, synovial wall resection, and so on. 4, wide indications, it is applicable to a variety of lesions in the joint. Few contraindications, such as poor physical conditions can not perform conventional surgery, but not necessarily contraindicated arthroscopic surgery. Arthroscopic surgery can treat all kinds of inflammation in the joints. Such as osteoarthritis synovitis, traumatic arthritis, rheumatoid arthritis, tuberculous arthritis, septic arthritis, exfoliative osteochondritis, etc., as well as synovial chondromatosis; chondromalacia patellae; osteochondroma (spurs), free body, synovial membrane wall, arthritis disorders, meniscus injuries, adhesion to the joint capsule, a variety of intra-articular fracture, adhesion of the various joints and joint activity is restricted, all kinds of joint pain with no known cause. Indications of arthroscopic surgery: 1. For diagnosis: ① Identification of non-infectious arthritis. From the observed synovial congestion and edema, the degree of cartilage damage and the presence or absence of crystals in the joints and other pathological changes, can help distinguish rheumatoid arthritis, osteoarthropathy and crystalline arthritis. ② Understand the site, degree and morphology of knee meniscus injury. ③Knee joint cruciate ligament and N tendon stop damage. ④ To know the damage of intra-articular cartilage, with or without intra-articular free bodies, etc., in order to confirm the diagnosis of osteoarthropathy, especially long-term chondromalacia of the patella. ⑤ Analyze the etiology of chronic synovitis, such as pigmented villous nodular synovitis. (6) Diagnosis of synovial crease syndrome and fat pad lesions of the knee. (7) Site and extent of rotator cuff rupture and biceps tendon adhesion. ⑧ synovial biopsy. 2, for the study of changes in intra-articular lesions: in the process of joint disease development, arthroscopy can be carried out many times, by taking pictures, videos or synovial biopsy, can obtain other diagnostic methods difficult to get the information on the diagnosis, treatment and prognosis judgment are very helpful. 3.Used for treatment: For some lesions of knee and shoulder joints, after clear diagnosis of the researcher, surgery can be performed with special instruments under the vision of the mirror, and satisfactory results can be achieved. For example, joint lavage and debridement, partial or total excision of torn meniscus of knee joint, meniscus edge split suture, anterior cruciate ligament repair, synovial crease excision, intra-articular adhesion release, tibial plateau or intercondylar ridge fracture revision, rotator cuff debridement, biceps tendon adhesion release and intra-articular free body removal, etc. In addition, for some lesions of large joints of limbs, special instruments can be used to achieve satisfactory results under microscopic vision. In addition, synovectomy is feasible for rheumatoid arthritis diseases of large joints of the limbs. Contraindications to arthroscopic surgery: 1, joint stiffness, because it prevents arthroscopic operation. 2, For those who have had arthrography in the recent past, due to the possibility of secondary chemical synovitis. False-positive results can be obtained if arthrocentesis is performed within 1 week after imaging. 3.Patients with bleeding disorders such as hemophilic arthritis, although intraoperative bleeding can be flushed with a large amount of saline to obtain a good field of vision for diagnosis, but a large amount of joint blood accumulation can occur after the operation 4.Local tissue infection. 5. Localized scars are inoperable. 6. Narrowing of the joint space.