Craig Wood, University of Kentucky
Abscess is an infection of the sensitive tissue of the foot. Abscesses result in varying degrees of lameness, depending on the severity of the abscess. Symptoms include the hoof being hot and an increased pulse. The abscess will take the path of least resistance and migrate up the hoof and break out at the coronary band. Once the abscess begins to drain, lameness usually subsides.
Abscesses can be located with hoof testers. Paring the area of the sole identified by the hoof testers is the quickest way to relieve pain and lameness. The sole will have a dryer, harder texture below the site of the infection. As the sole is thinned over the site of the abscess, it will become softer and spongy. Once the pus pocket is reached and drainage is initiated, pain subsides. Once drainage is established, flush the abscess with hydrogen peroxide or other suitable solutions. Irrigate the abscess with a germicide (iodine) and pack with a drawing agent (ichthammol). In persistent cases, a salve poultice applied directly on the hoof or soaking with epsom salts is required to draw the abscess to the surface.
Avoid cutting a large hole in the hoof when pairing or opening the abscess. In most cases, the less hoof removed, the quicker the horse can recover and return to active use.
A hoof crack is a visible vertical crack in the hoof wall. Cracks are referred to by location, such as toe, quarter, heel, or bar crack. Cracks run parallel to the tubules of the hoof. Cracks can be superficial to the hoof wall or can deeply penetrate the sensitive structures of the hoof. Dry and brittle hooves crack more easily than healthy hooves.
Treatment consists mainly of immobilizing the hoof crack, thus permitting sound hoof wall to grow down from the coronary band. Stabilizing cracking may involve side clips, burning the top of the crack, applying an acrylic, or rasping a half moon shape under the crack to remove the pressure that occurs when weight is applied on the hoof.
Sole bruises appear as red spots or specks on the sole and frog. They vary in size due to the extent of the blood vessels affected in the sensitive structures. The white line or the hoof wall also may be red. Sole bruises are caused by trauma from a sharp object or excessive weight-bearing of the sole on rocky ground. Barefoot horses should be trimmed so they walk on the hoof wall. Hooves that are trimmed too short are easily bruised on any ground. A bruised sole can be protected by shoeing with a pad and a flat concave shoe. Sole bruises rarely cause lameness unless they are severe. However, horses walking on hard surfaces may have tender hooves for a day or so due to a sole bruise.
Corns can be classified as dry or moist. Corns start out as bruises of the sensitive sole in the angle formed by the hoof wall and bars. This angle, where the wall and bars meet, is the seat area where corns originate. A dry corn is a red bruise in the seat of the corn area. The redness is caused by the horn tubular filling with blood from a ruptured vessel. A moist corn is yellow, with serum present.
Corns are caused by unequal pressure and concussion created by a conformational fault or faulty trimming. Corns can be caused by overtrimming the heels, heel calks (heel shoes that have small cleats on the end of the shoes), short-heeled shoes, unlevel shoes (shoes that have not been leveled properly after being shaped to fit the hoof but are simply nailed on the hoof), or leaving the shoes on too long.
Corns can be prevented by eliminating the causes. Pressure on the corn seat also may be relieved by trimming the sole between the bars and the hoof wall so that it is 1/8 inch lower than the wall.