The common causes of hand bending and tendon pain are as follows: First, finger flexor tenosynovitis, finger flexor tenosynovitis is a chronic aseptic inflammation due to repeated wear and tear of the flexor tendon sheaths, commonly seen in women and handicraft workers, the clinical manifestations of slow onset, gradually aggravated, early on in the palm side of the metacarpophalangeal joint there is a limited tenderness, gradually tendon sheaths are narrowed, tendon edema, tendon is difficult to pass through the narrow tendon sheaths in finger In severe cases, the fingers can be fixed in the straight or flexed position, unable to move. Treatment includes reducing hand activities, local physiotherapy, closed injection, injecting a mixture of lidocaine hydrochloride and prednisolone into the tendon sheath, which can promote the inflammatory reaction to subside, and if conservative treatment is ineffective, then the tendon needs to be loosened through surgery. Second, carpal tunnel syndrome, the pressure in the carpal tunnel is too high, the finger flexor tendon is squeezed, local pain symptoms can occur when the hand bends, wrist braking and wrist physiotherapy can relieve pain, conservative treatment is ineffective, then the carpal tunnel should be surgically loosened.