Pain in the crook of the arm usually refers to the presence of pain in the elbow joint area, which may be caused by chronic strain, acute injury, tennis elbow, cervical spondylosis, arthritis and other factors. 1. Chronic strain: prolonged exposure to cold in the elbow joint area may lead to muscle or fascia damage, causing aseptic inflammation, and then the symptoms of pain will appear, which may be aggravated when exposed to cold or exertion. 2. Acute injury: For example, if the elbow joint is struck by an external force, resulting in no fracture or soft tissue damage, it will cause elbow joint pain, which may be accompanied by swelling and activity limitation. 3. Tennis elbow: it may be related to prolonged elbow flexion and extension activities, which will lead to localized inflammation in the elbow joint, resulting in elbow joint pain, and in severe cases, it will lead to elbow joint activity restriction, unable to carry out normal activities. 4. Cervical spondylosis: After suffering from cervical spondylosis, the nerves innervating the upper limbs will be compressed and stimulated, which will cause elbow pain and may be accompanied by numbness of the upper limbs, neck and shoulder pain and other symptoms. 5. Arthritis: including various types of arthritis, such as degenerative osteoarthritis, rheumatoid arthritis, gouty arthritis, due to the presence of local inflammation or damage to the elbow joint will cause elbow joint pain, which may be accompanied by symptoms such as redness, fever and morning stiffness. If the pain in the crook of the arm lasts for a long time, it is recommended to consult a doctor for appropriate examination and treatment to avoid delaying the condition.