The sudden onset of fingertip immobility in the elderly is suggestive of distal muscle weakness. It is also necessary to test the proximal muscle strength by asking the person to lift his hands and feet and move his limbs to see if he can do some specific movements to determine if there is any impairment of the ipsilateral muscle strength. It is also necessary to ask whether there are symptoms of numbness, pain, and weakness on the ipsilateral side, and whether they are accompanied by dizziness and headache, nausea and vomiting, unfavorable speech, slurred speech, choking and coughing with water, and incontinence, etc. If there are, acute cerebrovascular disease, also known as stroke, including cerebral infarction and cerebral hemorrhage, is considered. It is necessary to go to the hospital immediately to perform cranial MRI or CT examination to clarify the diagnosis, provide timely treatment, and give drugs to nourish nerves and improve circulation to promote the functional recovery of the limbs.