Wrist flexion pain may be caused by wrist strain, wrist synovitis, trauma, rheumatoid arthritis and so on. 1. Wrist strain: If the patient’s wrist has long time activities, weight bearing or repeated flexion and extension of the wrist joint activities, it may cause wrist joint strain, which may lead to wrist flexion pain. 2. Wrist synovitis: if the patient’s wrist has been traumatized, cold and other stimuli, it may cause wrist synovitis, which will cause swelling and pain. 3. Trauma: Trauma to the wrist can cause injuries to the soft tissues around the wrist joint, such as tendons and ligaments, leading to pain when bending and lifting. 4. Rheumatoid arthritis: Rheumatoid arthritis caused by autoimmune disease will invade the wrist joint and cause pain. Patients with this symptom should go to the hospital in time to clarify the cause and then seek medical treatment.