The causes of arm pain after cervical spine surgery include cervical nerve root irritation and edema, local soft tissue injury, hyponatremia, and degeneration of the adjacent segment of the surgery. 1. Cervical nerve root irritation and edema: the cervical spine nerve root may be irritated during cervical spine surgery, resulting in edema of the nerve root, which leads to arm pain. 2. Local soft tissue injury: After cervical spine surgery, local soft tissue injury may be caused, and the soft tissue edema may compress the nerve root, resulting in arm pain, and the symptoms may be relieved after the soft tissue is restored. 3. Hyponatremia: after surgery, if the sympathetic excitability is reduced, it can lead to increased renal excretion of sodium, causing hyponatremia and painful muscle spasms, resulting in arm pain. 4. Degeneration of adjacent segments after surgery: after surgery can lead to secondary degeneration of the cervical vertebrae in the adjacent segments of the surgical site, and then compression of the nerve root and other symptoms of arm pain. Arm pain after cervical spine surgery may also have other pathological factors, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.