Swelling in the ankles, feet, or legs is frequently due to fluid buildup, also called oedema. This happens when extra fluid leaks from blood vessels and accumulates while in the surrounding tissues. Some common causes of swollen ankles and feet involve:   There's a difficulty with data submitted for this https://www.sgvascularctr.com/swollen-leg-why-do-i-have-it-and-what-can-i-do/