Several lameness problems can exist in the rear (palmar) half of a horse’s foot; most bear the very general title of “heel pain.” The real problem is that without very careful diagnosis, lameness in this general area might be attributed to the wrong structures within the foot, and treating the wrong structure is ineffective at best. Additionally, understanding what structures are damaged is essential to understanding just how that foot’s function is affected.

At the recent American Association of Equine Practitioners convention, held Dec. 2-6, 2006, in San Antonio Texas, one practitioner sought to clarify veterinarians’ understanding of this complex area and its function. Andrew Parks, MA, VetMB, MRCVS, Dipl. ACVS, professor of large animal surgery and head of the department of large animal medicine at the University of Georgia, presented a very detailed anatomical review of the palmar foot with state-of-the-art computerized imagery from the Glass Horse project (www.3dglasshorse.com), and discussed functional anatomy of the palmar foot in no less detail.

Beginning to Understand Heel Pain

Parks noted that “heel pain” is not a very specific diagnosis because there is no clearly demarcated division between the heel and the dorsal (front) aspect of the foot, and many structures span this division. Additionally, most practitioners use the term “heel pain” to refer to any lameness that is dispelled with a palmar digital nerve block. The trick is to identify which structure in that area is causing the pain–is it the navicular bone? The ligaments supporting the navicular bone? The deep digital flexor tendon? The ungual cartilages? Advances in diagnostic imaging, such as magnetic resonance imaging (MRI), have allowed veterinarians to begin making such distinctions in living horses for the first time, he commen