A heel spur is a calcium deposit on the underside of the heel bone. On an X-ray, a heel spur protrusion can extend forward by as much as a half-inch. Without visible X-ray evidence, the condition is sometimes known as "heel spur syndrome."

Although heel spurs are often painless, they can cause heel pain. They are frequently associated with plantar fasciitis, a painful inflammation of the fibrous band of connective tissue (plantar fascia) that runs along the bottom of the foot and connects the heel bone to the ball of the foot.

Treatments for heel spurs and associated conditions include exercise, custom-made orthotics, anti-inflammatory medications, and cortisone injections. If conservative treatments fail, surgery may be necessary.

Causes of Heel Spurs

Heel spurs occur when calcium deposits build up on the underside of the heel bone, a process that usually occurs over a period of many months. Heel spurs are often caused by strains on foot muscles and ligaments, stretching of the plantar fascia, and repeated tearing of the membrane that covers the heel bone. Heel spurs are especially common among athletes whose activities include large amounts of running and jumping.

Risk factors for heel spurs include:

• Walking gait abnormalities,which place excessive stress on the heel bone, ligaments, and nerves near the heel

• Running or jogging, especially on hard surfaces

• Poorly fitted or badly worn shoes, especially those lacking appropriate arch support

• Excess weight and obesity

Other risk factors associated with plantar fasciitis include:

• Increasing age, which decreases plantar fascia flexibility and thins the heel's protective fat pad

• Diabetes

• Spending most of the day on one's feet

• Frequent short bursts of physical activity

• Having either flat feet or high arches

Symptoms of Heel Spurs

Heel spurs often cause no symptoms. But heel spurs can be associated with intermittent or chronic pain -- especially while walking, jogging, or running -- if inflammation develops at the point of the spur formation. In general, the cause of the pain is not the heel spur itself but the soft-tissue injury associated with it.

Many people describe the pain of heel spurs and plantar fasciitis as a knife or pin sticking into the bottom of their feet when they first stand up in the morning -- a pain that later turns into a dull ache. They often complain that the sharp pain returns after they stand up after sitting for a prolonged period of time.