The diseases that need to be alerted to the numbness of the arm are cervical spine disease, cerebral infarction, peripheral neuritis and so on. 1. Cervical spine disease: cervical spondylosis or cervical spinal stenosis, cervical spine dislocation and other cervical spine diseases will compress the nerves, resulting in inflammation of the nerves, damage, and thus numbness in the arm. 2. Cerebral infarction: impaired blood circulation in the brain can lead to ischemia and hypoxic necrosis of local brain tissues, thus causing a series of neurological deficits such as arm numbness. Generally speaking, arm numbness is common in cerebral hemisphere ischemia, which requires head CT or MRI examination to confirm the diagnosis. 3. Peripheral neuritis: multiple peripheral nerve damage caused by a variety of reasons, induced peripheral neuritis, which will also appear the symptoms of arm numbness. The causes of arm numbness are many, it is recommended to go to the hospital in a timely manner for relevant examinations, a clear diagnosis and standardized treatment.