RELEVANT ANATOMY

THE heel bulbs are covered by a layer of haired skin. Under the skin is part of the digital cushion – the elastic tissue pad that underlies the frog and is involved in shock absorption. Outside this are the collateral cartilages: paired leaf-like structures that lie partially within the hoof and partially under the coronary band and heels. The deep digital flexor tendon runs between the digital cushion and the back of the pastern bones as it travels down into the hoof, over the navicular bone and the back of the coffin joint.