Patrick Loftin, DVM
Daniel J. Burba, DVM Dipl. ACVS
Horses' hooves are formed of insensitive, cornified material called horn. Inside the hoof capsule lie bone, joints, tendons, ligaments and other soft tissues. While the hoof capsule is designed to protect these structures and provide the horse with a platform to support its weight, traumatic events can puncture the hoof and affect the deeper, sensitive tissues. Puncture wounds often occur from stepping on nails, screws or other such objects.
What are the clinical signs?
Horses that have sustained puncture wounds to the foot are often extremely lame. The opening of the wound may or may not be evident during physical examination. Focal sensitivity to hoof testers will likely be seen as well. After the initial exam, if a puncture wound is suspected, radiographs are often used to determine the location and depth of the injury. A metal probe may be inserted into the wound tract to further illustrate the location of the puncture, as the metal will be easily seen on radiographs. Liquid contrast material, which is also easily seen on radiographs, may also be injected into the wound tract or into a joint space if it is suspected that the joint may be affected by the injury.
Treatment of deep puncture wounds.
Treatment of hoof puncture wounds revolves around removing any foreign objects and debris from the foot. This may involve surgical debridement. General anesthesia is often needed to allow adequate surgical debridement. After the initial surgical procedure, horses are treated with antibiotics to fight the possibility of infection, as most foreign objects and the hoof itself harbor large numbers of bacteria. A tetanus toxoid vaccine is also given as early as possible after the injury occurs, as the deep tissues of the foot can provide a perfect environment for Clostridium tetani to grow and release toxins. Anti-inflammatory drugs, such as phenylbutazone, are also administered to relieve inflammation and pain.
During the healing, the foot is wrapped in a clean, dry, medicated bandage. After the wound has started to heal, a special shoe with a protective plate called a medicine plate shoe is placed on the foot to protect the wound. The plate is made so that bolts can be unscrewed to remove the plate to medicate the wound. This is continued until the wound is totally healed.
Due to the large amount of important structures that are located in the hoof capsule, puncture wounds to the foot may be disastrous. Prompt diagnosis and treatment may lead to a better outcome.