Elderly people suddenly foot pain, need to look at the specific parts of the pain, if the big toe pain localized with redness and swelling, may be caused by gout. Because the elderly renal failure, uric acid excretion disorder caused by this pain is very sudden, the pain is more intense, localized redness and swelling phenomenon, usually need to test uric acid, if uric acid is relatively high, it can be confirmed to be caused by this disease, you can eat a little colchicine, febuxostat, drink more water. If the pain is on the soles of the feet, consider plantar fasciitis, which may be related to too much walking. If it is heel pain, consider heel fat pad inflammation, which is caused by the shrinkage of the fat pad after getting older. There is also the possibility of bone tumors, which are characterized by localized swelling and lumps. When you have foot pain, you need to go to the hospital for further examination to identify the cause for treatment.