Tenosynovitis of flexor tendon stenosis is a common and frequent disease in orthopaedics and traumatology. It belongs to the scope of ancestral medicine tendon disease. The main manifestations are unfavorable flexion and extension of the affected finger, joint pain, and functional limitation. Flexor tendon stenosis tenosynovitis, also known as “trigger finger”, “popping finger”, refers to the flexor tendon and its fibrous sheath due to repeated injury resulting in aseptic inflammation, manifested as the metacarpophalangeal joint popping and pain. It is mostly seen in the thumb, middle and ring fingers of manual workers. Cao Yun, Department of Acupuncture and Moxibustion, Nantong Chinese Medicine Hospital I. Application Anatomy of the palmar side of the metacarpal neck, there is a shallow groove and sheath ligament forming a tough and inelastic fibrous canal, namely the sheath canal. The tendons of the long thumb flexor, superficial finger flexor and deep finger flexor enter each finger through this canal. In front of the metacarpophalangeal joint of the thumb, there is a pair of seed bones whose cartilaginous surface forms the joint inside the joint capsule, while its back surface is rough outside the joint capsule, through which the flexor tendons of the thumb pass and are encircled by the annular ligament, which becomes the anatomical factor for the future occurrence of tenosynovitis. (2) Chronic strain and injury (l) chronic strain and injury: the production workers’ metacarpophalangeal joints overflexion and extension activities for a long time, so that the deep and shallow flexors rub against each other, or long-term hand-held tools, fiber sheath by hard objects and palm bone extrusion, and lead to aseptic inflammation of tendons and microsheaths. (2) Anatomical factors: The lesion is likely to occur at the beginning of the fibrous sheath of the flexor tendon corresponding to the metacarpal head, and in the thumb, at the annular sheath formed by the bone and ligament at the metacarpophalangeal joint, which are relatively narrow bony fibrous sheaths and are anatomical factors for tenosynovitis. (3) Hypertrophy of the seed bone or thickening of the ligament: the tendon sheath of the flexor tendon of the thumb is narrowed, mostly in children. (4) Systemic factors: such as postpartum, rheumatic and rheumatoid connective tissue diseases, etc. The lesion is characterized by edema of the fibrous canal, followed by fibrosis, thickening of the sheath, formation of circular stenosis of the canal lumen, and even cartilage degeneration and calcification of the sheath. The tendon at the lesion is enlarged in the shape of a pike, with a dark yellow color and loss of its original luster. When the enlarged tendon is stuck by the narrow tendon sheath, the flexion and extension is limited, if the active or passive flexion and extension is forced, the enlarged tendon squeezes through the narrow tendon sheath and a popping action and sound occurs, when the enlarged tendon does not pass, the affected finger cannot flex and extend, that is, atresia. (3) Clinical symptoms and signs (1) Most commonly seen in workers engaged in packaging, textile, sewing, binding, painting, mechanical assembly, etc. who rely on finger force for a long time or need to hold hard objects. The thumb, middle and ring fingers are more common, and the right hand is more common. It can occur in a single finger or in several fingers, the latter accounting for about 20%. It is more common in women than in men, and is more common in young adults. The onset of the disease is slow and worsens day by day. (2) In the early stage, patients only feel soreness and discomfort in the metacarpophalangeal joint in the morning, and the fingers are stiff and inflexible, which can disappear after activity. After work, finger movement is limited, and there may be limited soreness on the palmar side of the metacarpophalangeal joint, sometimes radiating to the wrist. (3) “Atresia” phenomenon: With the further narrowing of the sheath and further expansion of the tendon, the expanded part of the tendon will not be able to pass through the narrow sheath when it slides, and a popping sound will occur. In severe cases, the finger is stuck in extension or flexion, resulting in “atresia”, which can only be unlocked by passive flexion or extension, and a popping sound occurs, which obviously affects the movement of the finger. (4) Nodule-like elevation can be palpated on the palmar surface of the metacarpophalangeal joint with obvious pressure pain, and there may be frictional and popping sensation at the nodule during extension and flexion. (5) Flexion resistance test: make the affected metacarpophalangeal joint straight, and then ask the patient to actively flex the metacarpophalangeal joint after the examiner applies resistance to counteract, if pain is induced, it is positive. Tenosynovitis is a common disease in orthopedic surgery, and the traditional western medical treatment is hormonal closure and surgery. Sealing treatment has a high recurrence rate, while surgical treatment is highly invasive and leaves scarring after surgery. The treatment of stenosing flexor tenosynovitis with minimally invasive closed release surgery is a targeted treatment for its pathogenesis, so it has remarkable efficacy, less interference with normal tissues, almost no damage, almost painless operation, less patient pain, no incision, no bleeding, short time, most of which can be completed within 5-10 minutes or the advantages of immediate effect, which shows the scientificity and reliability of minimally invasive closed release surgery with needle knife. It also further confirms the close correlation between tendon compression and its anatomical structure and the adhesions between the compressed tendon and tendon sheath. The patient is usually treated once, and if necessary, the treatment is repeated once after half a month. After the operation, the patient is instructed to start functional exercises for half a month after the next day, which can improve the efficacy. Needle knife release has gradually replaced open surgery in the treatment of this disease.