The causes of numbness in the lower extremities of the elderly are mainly considered as follows: firstly, if the disease is of acute onset, it is mostly seen in arterial lesions, such as cerebrovascular stenosis or cerebrovascular hemorrhage, cerebral infarction and other diseases. The second aspect is to consider optic neuropathy, such as acute myelitis, multiple sclerosis, polyneuritis, or peripheral nerve damage due to endocrine diseases, which can cause numbness in the lower limbs of the elderly. The third aspect, tumor lesions, such as tumors in the cervical spine, can cause numbness in the lower extremities of the elderly. Fourth, autonomic nerve dysfunction, poisoning or malnutrition can cause numbness in the lower limbs of the elderly. The fifth aspect, some injuries caused by degeneration, such as disc herniation, cervical spondylosis, thoracic spinal stenosis.