Puncture wounds to the equine foot are encountered frequently by both farriers and veterinarians. Puncture wounds are classified as indirect or direct.
With an indirect puncture wound, foreign material gains entrance to the foot through the sole wall junction (white line) or a crack in the hoof and migrates through the tissue until it is recognized by the horse’s immune system and forms an abscess.
Direct puncture wounds are caused by a sharp object (wire, nail, glass) penetrating the ground surface of the foot, either through the sole or the frog (Figure A). In many cases, direct puncture wounds can be life-threatening.
As with many foot problems, the farrier is often the first to observe the lameness when the horse is taken out for hoof care.
If a horse is severely lame and still has a foreign object embedded in the bottom of the foot, it’s important not to pull it out. Instead, call a veterinarian immediately so a radiograph can be taken to determine the internal location of the object (Figure B).
The radiograph will reveal the depth and direction of penetration and the structures involved. This helps provide information about potential problems associated with the injury and provides a reference for the initial appearance of the involved structures and the location of the object. Due to the fibroelastic nature of the frog, puncture wounds to this area often seal, concealing the point of entry.
In many instances of puncture wounds, a surgical wound must be created to allow drainage from the injured area. This prolongs healing time and necessitates the use of a treatment plate.
Advantages of the treatment plate include eliminating the need for daily bandaging and the increased ease of observation and treatment of the affected area. A treatment plate also provides support for the foot and takes pressure off the injured area.
In addition, since a treatment plate will not wear through like a bandage, the horse can often be allowed controlled exercise.
The shoe in use at the time of the injury, whether steel or aluminum, can frequently be used to attach the treatment plate. However, a straight bar should be welded into the shoe to provide stability to the foot and plate. We prefer to construct treatment plates from aviation grade plastic available in a 1/4- or 3/8-inch thickness (1) (2).
This method has proven successful for both treatment and protection of the injured area. While a horse with such an injury should ideally be confined to a stall, this is not always possible or advisable. When it’s necessary to turn a horse out, a treatment plate allows the horse to be turned out without contaminating the wound. This type of plastic is inexpensive, easy to work with, very forgiving to one’s tools and extremely durable.
1. Wyndgate Farrier & Equine Supply, 16411 N. Cave Creek Rd., Phoenix AZ 85032.
2. Jan Young, DVM, personal communication