Possible causes of unbearable pain in one arm of cervical spine include frozen shoulder, cervical spondylosis, neck tumor, lymph node metastasis of malignant tumors, etc. Treatment includes conservative treatment, surgical treatment, chemotherapy, radiotherapy and so on. 1. Frozen shoulder: At the initial stage, patients with frozen shoulder can use some medicines to relieve symptoms, such as Celecoxib, supplemented by physiotherapy, acupuncture, massage, etc. Arthroscopic adhesion release surgery can effectively relieve pain symptoms, and it is recommended that eligible patients undergo surgery as soon as possible. 2. Cervical spondylosis: Neurogenic cervical spondylosis is mainly manifested as radiating pain in one side of the neck, shoulder or upper extremity nerves. If the pain is severe, surgical treatment should be considered to relieve the nerve compression in time in order to effectively relieve the pain symptoms. 3. Cervical tumor: thyroid cancer and cervical spine tumor in the neck can also compress the brachial plexus nerve and cause pain in one side of the upper limb, which is mainly treated by surgery, with complete resection of the tumor during the operation and adjuvant chemotherapy or radiotherapy according to the condition after the operation. 4. Lymph node metastasis of malignant tumors: lung cancer, gastrointestinal malignant tumors can be metastasized to supraclavicular lymph nodes, which can cause lymph node enlargement and compression of brachial plexus nerves. Usually, the presence of supraclavicular lymph nodes suggests that the malignant tumors have been in the advanced stage, which can be mainly controlled by comprehensive treatment, including chemotherapy, radiotherapy, targeted therapy, immunotherapy, and so on. If you have cervical spine arm pain, we suggest that you go to the hospital as soon as possible to find out the cause and treat it accordingly.