Flexor Tendinitis of the Finger

　　1. Etiology

　　Chronic aseptic inflammation caused by mechanical friction of the flexor tendons' stretching and contraction.

　　2. Pathogenesis

　　The onset site of tenosynovitis of the flexor tendons of the fingers is at the starting part of the fibrous sheath of the flexor tendons corresponding to the metacarpal head (i.e., A1 pulley). Here, a relatively narrow sheath entrance is formed by a thicker annular fibrous tenosynovium and the metacarpal head. Although the tenosynovium of the thumb is connected to the wrist bursa, there are two sesamoid bones at the metacarpal head, and the passage is narrow. When gripping objects, the tendons slide and tighten, and the tendons bend at the pulley of the metacarpophalangeal joint, with the most friction. The tenosynovium is also subjected to the front and rear compression of the object and the metacarpal head, making it prone to injury. Gradually, it increases and causes narrowing.

　　1. The most serious complication of tenosynovitis of the flexor tendons of the fingers should be suppurative infection. If not treated in time, the necrosis of the tendons after suppurative infection will cause the finger to lose its functional activity. The pus can also flow into the adjacent finger tenosynovium and palm space, causing total hand disability.

　　2. Functional limitation, due to the affected tendons' extensible function caused by tenosynovitis, there will be a manifestation of functional limitation. However, in general, there will not be serious functional limitation, and it will be significantly relieved after hot compress.

　　1. General Symptoms

　　The onset is gradual and is common in housework and manual laborers, with middle-aged and elderly women being more common. Any finger can be affected, but the thumb, middle finger, and ring finger are most common. The main manifestation is localized pain on the palmar side of the metacarpophalangeal joint and limited finger movement. As the narrowing of the tenosynovium worsens and the tendons are compressed, they become葫芦-shaped. The expanded part will be difficult or unable to slide through the narrow tenosynovium, causing the finger to remain in a straight or屈曲 position, resulting in a locking phenomenon.

　　2. Local Signs

　　During the examination, a nodule can be felt at the local tender spot on the metacarpal head of the patient. When the fingers are flexed and extended, the nodule can be felt sliding, but it is often obstructed due to the narrowing of the tenosynovium. When continued force is applied, it can suddenly slip through, similar to the trigger of a trigger, accompanied by a popping or jumping sound, with significant pain. Therefore, this disease is also known as trigger finger, popping finger, and plucking finger, etc.

　　1. Do not work for too long continuously. After finishing work, rub your fingers and wrists, and then soak your hands in hot water.

　　2. When washing clothes in winter, it is best to use warm water. After a snowfall, when clearing the snow, wear cotton gloves to prevent coldness in your hands.

　　3. Gently clench your fist and then open it, extending your fingers straight. Repeating this exercise repeatedly can help alleviate pain.

　　4. Sufficient rest is also very critical, hand movements should be reasonable and moderate exercise.

　　1. General Symptoms

　　The onset is gradual, common in housework and manual workers, and is more common in middle-aged and elderly women. Any finger can be affected, but the thumb, middle finger, and ring finger are most common. The main manifestations are localized pain on the palmar side of the metacarpophalangeal joint and limited finger movement. As the tenon stenosis becomes more severe and the tendons are compressed, the parts become葫芦-shaped, and it is difficult or impossible to slide through the narrow tenon sheath. When the fingers stop in the extended or flexed position through the narrow tenon sheath, locking phenomena occur.

　　2. Local Signs

　　During the examination, a nodule can be felt locally at the patient's metacarpal head where there is tenderness. When the fingers are flexed and extended, the nodule can be felt to slide, but it is often obstructed by the stenosis of the tenon sheath. When continued force is applied, it can suddenly slide over, similar to the trigger of a trigger finger with a click or jump-like pain, so the disease is also called trigger finger, click finger, and plucking finger, etc.

　　Disease diagnosis can be made according to the medical history, clinical symptoms and signs, and the appearance of trigger finger click.

　　In addition to conventional treatment, patients with finger flexor tenosynovitis should pay attention to light diet, avoid eating spicy and刺激性 food, and stay away from greasy food, which can help the disease recover faster.

　　Firstly, Treatment

　　1. Non-surgical Treatment:Non-surgical treatment is often effective, such as reducing hand activity, applying traditional Chinese medicine safflower oil and other blood-activating and anti-inflammatory drugs, applying plasters, and taking non-steroidal anti-inflammatory drugs. Local anesthetic treatment can be performed if necessary, injecting a suspension of 0.5-1ml lidocaine and triamcinolone acetonide into the tenon sheath. Early cases may show improvement with just one injection, and for refractory cases, once a week, not exceeding 4 times.

　　2. Surgical Treatment:For those who are ineffective after treatment with the aforementioned methods, small needle knife release or tenotomy can be performed. Make an incision at the palmar transverse crease, separate directly to the sheath with forceps to avoid injury to the digital vascular nerve bundle. Make a longitudinal incision of 2cm in the tenon sheath, and remove part of the tenon sheath, release the adhesion of the tendons, and instruct the patient to move the fingers until the click disappears.

　　Secondly, Prognosis

　　Good Prognosis.