The most common causes of hand and foot weakness in the elderly are as follows: First, cerebrovascular disease: cerebrovascular disease commonly includes cerebral infarction and cerebral hemorrhage, which has a sudden onset, and in addition to weakness of the hands and feet, there are sensory disorders, urinary and fecal disorders and other symptoms. It is recommended to go to the neurology department of the hospital, and make a clear diagnosis by reviewing the cranial CT or MRI, and the diagnosed patients need to be hospitalized. Secondly, hypokalemia: patients may have hypokalemia. Elderly people’s diet is not standardized, and the intake of vegetables and fruits is relatively low, coupled with the decline of absorption function. If sweating too much, it is easy to lead to hypokalemia, which is the main reason for the weakness of hands and feet. Third, inflammation: pay attention to exclude whether there is any inflammation in the body, especially pneumonia. Clinical often see many old people suddenly appear hand and foot weakness, through the examination found to be pneumonia, so pneumonia can also cause the elderly hand and foot weakness.