Numbness in the right hand and arm may be caused by cervical spondylosis, which is mainly caused by a herniated cervical disc compressing the cervical medulla, and the patient may also have numbness in the right lower limb or right foot, and some patients may have numbness in all four limbs, and in severe cases, they may also have abnormal urination and defecation, and may have urinary retention and incontinence. It may also be caused by acute cerebrovascular disease, including cerebral hemorrhage and cerebral infarction, etc. It is recommended to go to the neurology department to improve the cranial CT or MRI examination for a clear diagnosis.