Pain in the arm and back is commonly caused by cervical spondylosis, periarthritis of the shoulder joint, and shoulder trauma, as follows: 1. X-rays and MRI scans of the cervical spine will reveal the location and extent of the lesion. 2. Shoulder periarthritis: This can also cause pain in the upper side of the arm and the upper back, accompanied by pain and limited movement of the shoulder joint. 3. Shoulder trauma: Dislocation of the shoulder joint fracture can cause local edema, resulting in arm pain and back pain, accompanied by limited movement of the shoulder joint. The diagnosis can be confirmed by X-ray examination. Early diagnosis and early treatment can provide complete relief of arm and back pain.