Horses can have hoof imbalance in the sagittal plane (front to back) or medial-to-lateral plane, and both types of imbalance can affect both front feet and hindfeet. These imbalances can result in poor performance or lameness. Limb conformation, distal limb wounds or injuries, and poor shoeing or trimming can lead to these imbalances.
Hoof imbalances in the sagittal plane were historically described in terms of the angulation with respect to the distal interphalangeal joint (DIP joint). For example, a "broken-forward" horse shows an upright hoof and may be clubfooted. A "broken-back" horse can demonstrate a long-toed or low-heeled conformation, and many broken-back horses have a negative palmar/plantar angle on radiographs; see sagittal hoof imbalance image.
Courtesy of Dr. Valerie J. Moorman.
Physical examination of the foot, including the dorsal, palmar/plantar, and solar surfaces, can be helpful in identifying hoof imbalances. Dynamic examination with the horse walking in hand can also be helpful.
Radiography of the foot can aid in the evaluation of hoof imbalance; dorsopalmar and lateromedial radiographs should be taken. It is important that the dorsopalmar view be straight on, with the horse bearing weight evenly and with the limb vertical and underneath the horse’s body; artifacts of uneven weight bearing are still common with this view.
In many horses, changes in trimming and shoeing can help correct hoof imbalances. Not all hoof imbalances require treatment, however, because many are conformational in origin. In horses without lameness, drastic changes in trimming or shoeing have the potential to induce lameness.
