A heel spur is a painful condition that is caused by the accumulation of excessive calcium under the heel of the foot. The heel bone is connected to the bottom of the foot by durable connective tissue called fascia. If the layers of connective tissue become damaged or begin to degenerate due to wear and tear, plantar fasciitis may develop. This causes calcification, the abnormal buildup of calcium on the heel bone. As it accumulates, a calcified protrusion called a spur may become visible on an X-ray.

Heel spurs usually form under the base of the foot or the back of the heel bone. Spurs that develop underneath the foot may visibly protrude through the skin. In addition, plantar fasciitis as well as heel spurs may eventually lead to chronic pain that persists for three or more months, especially if the sides and base of the heel bone have been affected. A large heel spur can affect movement and prevent an individual from walking or even standing properly.

Treatments that have proven to be effective for heel spurs include injections that contain a combination of steroids and anesthesia as well as radiofrequency ablation. However, a bone spur that begins to protrude excessively may need to be removed through surgery.