Plantar fasciitis (inflammation of the plantar fascia) is the most common cause of heel pain. It is common in several groups of people, including runners and other athletes, people who work that require a fair amount of walking or standing on their feet (especially if it is done on a hard surface), and in some cases it is seen in people who have put on weight -- either by dietary indiscretion or pregnancy.

The plantar fascia is a broad ligament-like structure that extends from the heel bone to the base of the toes, acting like a thick rubberband on the bottom arch of the foot. With a few extra pounds on board, or with activities such as exercise, the plantar fascia can develop microtrauma at its insertion into the heel bone, or anywhere along its length. This causes pain which can be quite severe at times.