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NEW CONCEPT IN FOOT LAMENESS Report of a clinic held by Dr. Barbara Page, DVM Dr. Barbara Page, a Littleton, Colorado, equine practitioner, has held several successful foot lameness clinics, describing her concepts of "Natural Foot Balance" shoeing and lameness evaluation9 Teaming up with Farrier Gene Ovnicek and Dr. Robert Bowker, the three have developed some new theories about soundness in the lower limb of the horse and shoeing in a manner that complements natural hoof physiology. Some of their ideas go counter to age-old traditions in shoeing and lameness evaluations9 However, their ideas are gaining many loyal followers among veterinarians and horse owners. Dr. Page says, "Most of the research on the horse's foot in the past 300 years has been done on domestic horses which, through necessity, wear shoes. However, Mother Nature designed a foot which survived and multiplied in hard rocky terrain for millions of years without shoes." Her innovative ideas about podiatry began in 1995 when she was observing a gathering of feral horses in Northern Colorado. One of the horses in the wild horse roundup died in the process and Dr. Page obtained the limbs of the dead horse for study. She wanted to learn how it was possible for wild horses to remain sound in the rough terrain they lived in without the benefit of shoes. A study of sound domestic horses compared to feral horses was done by Ovnicek, Page, and Bowker through the non-profit foundation "Colorado Human/Animal Resource Foundation" (CHARF). An evaluation of the shape, size, and angle of the hoof capsules was made, along with radiography, imprinting, gross anatomy and histologic studies. Some of these results were presented at the AESM meeting by Dr. Bowker in 1997. CHARF has followed this work with other studies on anatomy, radiology, and biomechanics. Because of the clinics on the subject, and positive word of mouth from pleased clients who now have the soundest horses in competition, the concept of "'natural foot balance" has gained the interest of most specialists in equine foot care and management. One of the concepts of this group is that the tissues in the equine digit function for survival of the species. The functions are: support of the horse's mass, absorption of concussion when landing of the limb, movement of the horse, and nutrition and protection of internal structures. The tissues in the foot can adapt to the use they are given, just as a muscle hypertrophies or atrophies. The work done by this group is illustrating what the functions are of different tissues in the foot, and how 9 . rY those ussues adapt to different stresses9 For instance, in the feral horse, mass is supported on the frog and sole callus. The hoof wall of the feral horse is worn away because the feral horse travels many miles daily over rocky terrain to sparse water sources. In the domestic situation, a barefoot horse may use the hoof wall for support if the wall grows beyond the frog and sole callus and is not worn away by the environment or a farrier's rasp. In a shod horse, the weight is borne on the hoof wall and laminae because the shoe is applied to the hoof wall. This lifts the frog off the ground so there is no support of mass on the frog. A significant difference in laminae is observed in horses bearing weight on the hoof wall versus ones bearing weight on the frog. They have shown that the laminae tissue has some ability to adapt to the needs placed upon it. Of equal importance to natural balance is physiologic biomechanics inside the hoof. The biomechanics of the coffin joint are greatly effected by the distance of the breakover of the 784 JOURNAL OF-EQUINE VETERINARY SCIENCE
