If the left leg numbness is caused by cerebrovascular disease, such as cerebral infarction, transient ischemic attack or microhemorrhage in the brain, the patient should be treated with anti-platelet aggregation, circulation improvement and blood circulation treatment for ischemic cerebrovascular disease, and dehydration to reduce intracranial pressure for hemorrhagic cerebrovascular disease, and surgery if necessary. Patients who still have left leg numbness after the acute stage can undergo acupuncture and rehabilitation. Secondly, if the left leg numbness is caused by lumbar spine disease, such as lumbar disc herniation or lumbar spinal stenosis, the patient can be given lumbar massage, physical therapy, and if necessary, surgery.