A thorough examination and assessment of the equine foot forms an essential part of both the physical and lameness evaluations. Because foot problems are the most common cause of lameness, the examiner must have an accurate knowledge of foot anatomy and must be willing to perform a "hands on" approach to appreciate fully the problems that may be encountered. There are numerous causes of pain in the foot of the horse. These causes can be arbitrarily divided into (1) conditions of the hoof wall and horn-producing tissues, (2) conditions of the third phalanx, and (3) conditions of the podotrochlear region. Hoof problems would include hoof wall defects, such as cracks that involve the sensitive tissue; laminitis (systemic), laminar tearing (local caused by hoof imbalance), and separation or inflammation of the sensitive laminae from the insensitive laminae; abscess formation; contusions of the hoof causing bruising or corn formation; neoplasia; and pododermatitis (thrush or canker). Third phalanx problems include fractures of the coffin bone (types I-VII), deep digital flexor insertional tenopathy, pedal osteitis (generalized or localized inflammation of the bone), disruption of the insertions of the collateral ligaments, cyst-like lesion formation, and remodeling disease. Conditions of the podotrochlear region have been reported to include distal interphalangeal (DIP) synovitis/capsulitis, deep digital flexor tendinitis, desmitis of the impar (distal navicular ligament) or collateral sesamoidean ligaments, navicular osteitis or osteopathy, vascular disease of the navicular arteries, and navicular fractures. The common denominator of all these conditions is that they are characterized by pain that can be localized to the hoof. Like all examinations, the evaluation of the horse with foot pain requires a thorough history.
