The first time my horse had an abscess I thought he’d broken a leg. He was standing in his field holding up his leg, refusing to put any weight on it. I panicked. I called my (then) vet who came out and ran a battery of tests, including x-rays. Then my farrier showed up, snorted, and told me to fire my vet because it was crystal clear that it was an abscess. Ultimately, that abscess burst out the coronet band and left my horse uncomfortable for probably another week. With vet bills, it cost me $400!
Given that experience, you’d think that I would recognize the signs. But no. Yesterday morning when I went to feed my horses, I could tell that one of them was not quite right. It was just the way he was standing. He was resting his right hind and he looked, well, uncomfortable. This horse is very stoic and I just know when he looks pained, he usually is. Of course, a host of scenarios ran through my mind — pulled suspensory, kick, pulled muscle. But there was no swelling, no cuts and he looked sound at the walk. I took him out for a hack to see if he worked out of it, but a few steps at the trot convinced me he was not even close to sound.
I called my current vet who suggested an abscess based on my description. Sure enough, that’s what it was. He got worse throughout the day, holding his hoof up and refusing to put weight on it. A friend’s farrier was in the area and by paring the hoof he was able to find some red tinted horn, indicating bruising, so an abscess was definitely brewing.
Hoof abscesses are infections between the corium and the horn. The pus that occurs causes pronounced pain and lameness as the infection grows. Abscesses are caused when bacteria and moisture penetrates the white line, when a puncture occurs (for example, when a horse pulls a shoe and steps on a clip, or as a result of deep bruising.
The infection results in acute and sudden lameness, an increased digital pulse, heat in the foot, and sometimes swelling in the pastern or fetlock area. An abscess surfaces and drains either through the sole of the foot (if drained) or will bust out at the heel or the coronary band.
The standard treatment for hoof abscesses is to:
Locate the abscess using hoof testers to locate the sensitive area.
Drain the abscess. If possible, creating a way for the abscess to drain will result in a smaller hole that will heal more quickly. Typically, the farrier or vet pars the sole of the hoof the pressure from the abscess causes it to burst and the pus drains. At times, there might also be some blood. However, you do not want to dig a large hole in the sole, either. Often if the sole is thinned and you pick up the other foot, the added pressure can cause the abscess to break through, otherwise, you can soak the foot in hot water and epsom salts to soften the sole. Once the abscess drains, your horse should experience immediate relief.
Next, you should clean the hole with a betadine solution and pack the hole (defect) with betadine soaked cotton and then wrap the hoof (or put on a hoof boot) to keep dirt out of the hole.
Soak the hoof for 20 minutes once or twice daily in hot water and Epsom salts for several days, or until the horse is sound. The water can be quite hot. I like to heat it in an electric teapot. You add Epsom salts until no more will dissolve. I like to use a Davis soaking boot as I’ve had no luck at all trying to keep a horse standing with its hoof in a bucket! With a soaking boot, you can put your horse on the cross ties, or even in its stall during the soaking period.
Protect the hoof — and keep it clean — after soaking by bandaging it or wrapping it and covering it with a hoof boot. Here’s a link to a great photo essay on the best way to bandage a hoof. Keep it covered for about a week while the defect heals to keep dirt and bacteria from entering the hoof.
There is some debate as to whether chronic soaking (for several days) is an effective treatment. According to an article by Dr. Stephen E. O’Grady, an equine practitioner and farrier practicing in the Northern Virginia area, there is little documented research on the therapeutic value of soaking a horse’s hoof beyond the first 12-24 hours to localize an abscess:
There is no question that excessive moisture will damage the hoof wall. The more the foot is soaked, the more the hoof softens. The hoof wall quickly deteriorates, the wall begins to flake and separate and the loss of integrity allows it to expand or bend outward. At the same time, the white line width increases and the sole begins to drop and become closer to the ground. As the softening process continues, the horse begins to walk on the sole, creating another source of discomfort. Many times, this will mimic an abscess that has not completely resolved. It is believed that soaking damages the protective barrier on the foot (periople) and the widened sole wall junction thereby allowing additional microorganisms to penetrate and further damage the wall. Over-softening of the foot can potentially weaken it. The softened hoof wall does not hold nails well so it is difficult to replace or maintain a shoe on a chronically soaked foot.
Chronic foot soaking for an abscess can actually prolong the healing process. In many cases, the pocket resulting from the accumulation of exudate from the abscess will be prevented from draining and drying up as the softened structures of the chronically soaked foot compress the affected area.
Instead, he recommends applying a poultice.
The poultice provides a warm moist hydroscopic environment which stays in contact with the foot twenty-four hours a day but does not have the detrimental effects of continuous soaking. There are many good commercial poultices on the market. A medicated poultice [Animalintex®] is an excellent first choice when a poultice is indicated. The Animalintex® poultice, made of multiple layers of medication-impregnated cotton sheets, is immersed in hot water, the excess water is squeezed out and the poultice is applied to the foot, covering the ground surface and extending over the coronary band. The poultice has its own plastic outer covering to maintain heat. It is left in place for at least 48 hours. Moist heat applied to the coronary band may also help an abscess to break out spontaneously.
Another useful form of poultice is a combination of wheat bran and Epsom Salts (2 parts bran and 1 part salts). This poultice is cumbersome but has certainly withstood the test of time. Packing the foot with Ichthammol or a combination of Ichthammol and glycerin is also used frequently with good results reported.
Whichever poultice is used, it must be held in place with a bandage. An ideal foot bandage is a medium-sized disposable diaper covering the enclosed medication. For more padding, use multiple diapers. For a sweating effect, use plastic-covered diapers and duct tape. For more breathing, use non-plastic covered diapers and gauze bandage. The bandaged foot is protected as well as medicated. A rubber Easy Boot® can also be used for protection, but is difficult to place over a hoof that is bandaged with poultice.
What’s worked for me is to apply a poultice of Epsom salt paste and then putting an air-activated heat pad (like Thermacare) over it. The pad provides low-level heat for 8-12 hours. I then put vet wrap on to hold the poultice in place and cover it with a hoof boot. I have an oversized hoof boot that I use for this application; a hoof boot that fits normally won’t fit over a wrapped hoof. In my experience, this helps the abscess come to the surface. It also eliminates the need for repeated soaking.
This last time it worked like a charm. Today when I came to the barn, my horse was walking more comfortably.