The jamming of the middle finger when bending and straightening can be considered to be related to stenosing tenosynovitis, osteoarthritis, gout and other causes. 1. Stenosing tenosynovitis: common in middle-aged and elderly women, usually caused by chronic manual strain. Often, after flexor tendon strain, hyperplasia occurs, causing tendon sheath wear and proliferation. When the flexor tendon moves to a certain degree, it will jam onto the tendon sheath, resulting in jamming when bending back. 2. Osteoarthritis: Osteoarthritis is formed when degenerative changes occur in the joints. It not only leads to morning stiffness and pain in the finger joints (pain aggravated after activities) and other symptoms, but also leads to jamming when bending the finger joints, which seriously affects the flexibility of the finger joints. 3. Gout: When gouty arthritis strikes, gout stones may be produced inside the interphalangeal joints of the fingers. When the fingers move, the middle finger may appear stuck when bending or straightening. It is suggested that one should pay attention to the rest of the hand and avoid overwork, and should pay attention to local warmth to avoid getting cold and aggravating the symptoms. If the symptoms are serious, it is recommended to go to the hospital for examination and targeted treatment.