When a crack does not extend into the sensitive laminae, a notch or groove is cut into the hoof wall at the leading end of the crack. Whether the crack originates at the coronet or bearing surface, this treatment is aimed at preventing the hoof from splitting up or down its entire length. For cracks originating at the bearing surface, the wall on either side of the crack is shortened to help prevent expansion by removing weight from this portion of the wall. Shoes with clips positioned on either side of the crack are frequently used as another measure to prevent expansion of the crack.
Cracks that extend the entire length of the foot, go down into the sensitive laminae, or are accompanied by infection, usually cause lameness. Cracks that are this severe require more extensive treatment. Patching the hoof wall is commonly done to seal the crack and prevent infection of the sensitive structures.
The general procedure is to strip out the crack and fill it with some type of plastic material, epoxy glue, fiberglass, etc. In more severe situations, the crack is drilled out dovetail fashion, with tiny holes drilled on either side of the crack. The crack is laced with stainless steel wire to further hold it together and serve as reinforcement for the plastic material. Then the crack is filled with a plastic.
Heel cracks may require different treatments. Frequently the hoof wall behind the crack is shortened so that it does not touch either the ground or the shoe. A deep heel crack with accompanying bleeding or exudation will demand relatively radical treatment. The procedure is to remove the segment of horny wall behind the crack down to the sensitive laminae, apply antibiotic powder or ointment to the lesion, and bandage the foot with a pressure bandage for several days. The lesion is then treated with a drying agent such as 10% formalin or 7% tincture of iodine. A bar shoe may be used to protect the heel until this portion of the hoof wall grows out again.
It is important to pay close attention to any crack in the foot until it has completely grown out since it has a degree of weakness that can be likened to a split board. An important adjunct in all foot crack treatment is the liberal use of moisturizing hoof dressing on a regular basis.