There are several common causes of arm cramps: First, neurogenic cervical spondylosis, cervical disc protrusion compressing one side of the nerve, nerve stimulation generating impulses causing muscle spasm and pain in the upper limbs, cervical disc CT can be clear. Second, excessive exercise and strain, strenuous exercise of the upper limbs, excessive strain keeps the muscles tense for a long time, thus producing a large amount of acid such as lactic acid, which stimulates the muscles to produce spasm, cramps and pain. Third, hypocalcemia, mostly seen in the elderly, calcium intake is insufficient or excessive loss of calcium, prolonged calcium deficiency in the body is likely to cause muscle cramps, cramps, pain. Fourth, cold, low temperature is likely to cause muscle and joint stiffness, and activities without preheating are likely to cause cramps and pain.