Imagine one of every horse owner’s worst nightmares: you enter the barn or paddock to check on your horse, and find him unwilling to move. He’s holding one foot forward, a little off the ground, and when encouraged to walk, he almost hops to avoid putting weight on it. Your mind starts to race, thinking of all the things he could have done to himself. You inspect the hoof – no nail, no foreign object that you can see. The limb looks okay, there’s no swelling, and your horse is pretty calm, now that you think about it… what gives? You call your vet and ponder the possibilities.
A sudden onset of non-weight-bearing lameness in a horse is always concerning, and should be evaluated as soon as possible by your veterinarian. But there is good news here. Most of these cases have a quick and positive outcome, and the horses return to soundness within a few days. That’s because the majority of cases of acute lameness in one leg (with no sign of trauma or significant distress associated) are caused by a hoof abscess.
Horse’s hooves are amazingly sensitive structures, especially considering that at a gallop, just ONE of them will periodically support the entire weight of the horse. Anyone who has dealt with the crippling effects of laminitis can appreciate the age-old adage, “No foot, no horse.” (We’ll deal with the topic of laminitis in another blog.) When an abscess forms, it is generally due to one of two reasons; (1) direct trauma to the bottom of the hoof (aka the “sole” of the hoof), causing a bruise/hematoma which becomes infected, or (2) “tracking” of dirt and debris up the white line (the line between the sensitive and insensitive laminae, which connects the coffin bone to the wall of the hoof). These two things can probably occur together, creating a “perfect storm” for abscessation.
Luckily, abscesses are fairly classic and easy to diagnose. Application of hoof testers can localize the abscess and give your vet or farrier a good idea of where to start looking. Following a tract up the white line or in the sole with a hoof knife will typically yield a a nice black ooze, and sometimes a nice squirt! A lot of people think that because it’s an infection, it will be white pus. It actually comes out black due to the dirt that has made its way into the pocket.
If an abscess isn’t discovered immediately, the foot should be soaked in a warm betadine bath and it should then be wrapped with a poultice pad, such as Animalintex. This will soften the foot and allow the infection to come to a head, like a big pimple. After a few days of this, the abscess may either pop out of the sole or at the coronary band (called “gravel”). At this point, soaking should be continued for a few days and the foot should be kept clean and wrapped to prevent repeat infection.
Once an abscess has burst, whether by being opened from the bottom, horses will generally improve within 24-48 hrs. While your horse will be walking better, healing still needs to happen. You should discuss further options with your vet or farrier, such as shoeing or foot bandages once the abscess is gone.
Occasionally, a diagnosed foot abscess will go on longer than a few days. In these cases, re-evaluation by a veterinarian is recommended, and radiographs may be taken. It is possible for a hoof abscess to infect the deeper structures of the hoof, including the bone. This is a serious situation, and needs immediate and aggressive treatment.
As we approach spring (and MUD season), hoof abscesses are going to become even more common. So, if you notice your normally sound horse is limping badly on one leg, don’t panic. Check the bottom of the hoof for nails or other foreign objects (on a side note, if you see something actually sticking into the bottom of the foot, do your best NOT to pull it out. Protect the limb from further injury, and call a vet immediately!). Check for severe swellings which can indicate serious injury. Then feel the hoof – is it warmer than the rest? Can you feel an increased pulse at the back of the fetlock or pastern? It’s probably an abscess. Call your vet for an evaluation – in a few days, your horse will probably be well on his way to recovery.
