A horse is almost bound to experience a hoof problem during his lifetime. How serious it is and how it is handled could make the difference in his return to full soundness. During an early-morning presentation at the Thoroughbred International Exposition and Conference (TIEC) held in Lexington, Ky., June 20-22, Robert Hunt, DVM, MS, Dipl. ACVS, a surgeon at Hagyard-Davidson-McGee and Associates, discussed hoof anatomy and common hoof problems. Hunt has worked as a farrier for a number of years, and disorders of the feet comprise a considerable portion of Hunt's practice.

Hunt began his talk with the anatomy of the hoof. He presented numerous slides that illustrated the parts of the hoof and provided insight into circulation and hoof growth. The foot consists of the hoof capsule and internal contents, the corium, 11 ligaments, two tendons, the digital cushion, one synovial joint, one bursa, two and a half bones, lamella, and part of two cartilages. The corium, or coronary band region, is where hoof wall growth is initiated. The wall is thickest at the toe, and it gets thinner as it approaches the heels. Hunt said one disadvantage in the horse's hoof anatomy is this lack of wall thickness at the heels. This is because the horse should be landing on the heels since the heels provide the greatest amount of shock absorption.

Hoof wall growth averages one-quarter of an inch per month, taking between nine to 12 months to completely replace the entire hoof wall. Injuries to the border of the corium will be reflected as wall defects that extend downward as the wall grows.

Water content of the hoof varies from about 25% in the wall, to 33% in the sole, and 50% in the frog, according to ideal values based on past research. These values can differ based on the climate and the individual horse. The hoof wall is avascular (without blood vessels), however, circulation is of utmost importance within the hoof capsule. The hoof wall also does not contain nerves, therefore many hoof wall injuries that might look horrible to us might not bother the horse. Hunt said that he prefers to leave most hoof wall injuries to heal on their own