Heel spur syndrome is one of the more common and potentially most devastating injuries an athlete can have. The heel bone (calcaneus) is a thick, rectangular bone. At the bottom of the calcaneous is a heel pad to cushion the heel with the ground. There is also a ligament which runs longitudinal along the arch from the heel to the toes. This is called the plantar fascia, and it elevates, or supports, the arch. The plantar fascia is a tough, fibrous band composed of three slips. The middle slip is the thickest, followed by thinner medial and lateral slips, which are thickest at the heel region and become thinner at the metatarsal toe joints.

The spur formation is usually a shelf of bone, the entire width of the heel bone. It is formed by the continuous tearing away of the lining of the heel bone by the pull of the strong plantar fascia due to abnormal pronation of the foot during heel contact, midstance and the toe-off phase of gait. As the tearing effect occurs, a layer of new bone or calcium deposit forms, which eventually thickens and forms a heel spur. It is located at the insertion of the plantar fascia at the bottom of the heel bone. This bony prominence penetrates into the surrounding tissue as an irritant and can cause heel bursitis.

A heel spur manifests itself as a deep tenderness on the bottom of the heel. The pain may radiate into the sole of the foot. Actually, the pain is not due to the spur itself, but rather, to the fibrous bursae or sac which surrounds the spur. In its early stages, the heel spur syndrome has a characteristic pain cycle of greater soreness in the morning or after sitting for a long period of time. It becomes less painful after walking or jogging.

Depending on the severity of the deformity, pain may be present at rest or only after vigorous exercise. There may also be local swelling. The pain is usually tolerated. After a few weeks, a dull, aching pattern occurs.

Dr. Robert F. Weiss, a sport podiatrist, was a member of the Medical Advisory Committee of the 1984 and 1988 Olympic Marathon Trials. Weiss has a practice in Darien, The Foot & Ankle Institute of Darien, and resides in Westport. For information, go to www.therunningdoctor.net