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Published in the Horse Hoof Magazine.
WHY SHOULD WE WORRY ABOUT THOSE HEEL CRACKS?
By Heath Kizzier
A "heel crack" is the number one warning sign of thrush and frog disease. These cracks are not natural and there is a direct relationship between heel cracks, soft heels, tenderness, toe walking, and mysterious lameness.
The good news is: There is a solution.
WHERE DO HEEL CRACKS COME FROM?
A heel crack is formed by bacteria as it eats directly into the inner tissue of the foot. The bacteria digs in as deep as possible because the crack is warm and moist inside – the perfect bacteria breeding ground. The bacteria eats, the crack grows, and soon an open wound is created. Imagine if you had an eternally open wound in your heel - and then you walked around barefoot? A few results include infection, pain, swelling, gait change – not to mention a temperament that is far from perfect. In fact we’d be a moody, sore, irritated mess.
Open, untreated heel cracks are the prime cause of recurring thrush. Why? Often we will use our favorite product and treat active thrush and frog disease for a week or so. This generally kills most of the bacteria and hopefully rids the infection. But this is a temporary fix. We’ve won the battle, but war rages on. If we leave the heel crack unattended, unhealed, a multitude of bacteria and fungus will promptly reinvade. There is no way around it. Then, when moisture is introduced via rain, urine, or even water bucket slop-over, thrush and disease have everything it needs to restart the infection process.
It is important to note here that the “Black Goo” associated with thrush is actually the decayed, liquefied remains of tissue. So by the time we see the goo, the bacteria has been hard at work for weeks or even months. The black goo is a result of disease, not the cause.
HOW DOES A HEEL CRACK AFFECT THE ANATOMY?
Before we discuss treatment, we should take a moment to consider the wider-reaching consequences of a heel crack.
With each step a horse takes, the heel pad receives the entire brunt of his weight. It's a tiny 3 inch piece of tissue and hide. Nature intended the heel bulbs to be a slightly pliable, yet unified landing surface.
But what happens to the energy (the explosive power) of each step when the heel bulbs are abnormally separated by this open wound? Instead of landing the collective weight on the unified heel bulbs, that energy is now dividing into two halves. The two sides of the heel crack yawn open, further dissipating the energy and forcing it up into the soft tissue. “Energy” translates to strength, speed, endurance, stamina, and agility. A horse can never be at peak performance when his forward energy is being diffused in this manner. If we add the pain and tenderness caused by thrush, this horse is now a significant underdog under any circumstance.
A horse should NOT have a heel crack He should have a “dimple.” The dimple should be fully connected by tissue and hide.
HOW DO WE TREAT THE HEEL CRACK?
First we need to treat the underlying cause: Thrush and infection. It is preferable to choose a non-caustic product that will not burn the tissue. (This is important because if we burn the tender tissue inside the crack, the tissue is unable to stabilize before a new generation of bacteria invades.) In normal circumstances this treatment will take about a week. (NOTE: This is where most people stop all treatment. But there is more to do.)
Once we are comfortable that the bacteria and its damp breeding ground are eliminated, it is time to focus on the heel crack. (Also look for deep hairline cracks in the collateral grooves that seem to disappear into the frog.) All these cracks should be treated with a non-caustic, bacteria fighting product several times a week. The goal here is to destroy any and all bacteria that are trying to re-enter the cracks, which will otherwise re-start the thrush cycle. We should consider this as mandatory “maintenance.” The tissue will soon begin to grow out naturally. Depending on the depth of the cracks, and the overall health of the horse, this process will normally take 20-40 days.
We now know that this horse is susceptible to thrush and/or frog disease. He got it once, so odds are he will get it again unless we are vigilant. It is good practice to continue using the non-caustic bacteria-fighting product on a regular basis (3-4 times per month, and more often during wet weather). Apply on the heel, in the collateral grooves, and along the exposed white line areas, as these areas are the prime access points for bacteria and fungus. Additional preventive measures include keeping the stabling environment clean and dry, daily hoof cleaning, good exercise, proper diet, and very close observation.
SOME FINAL WORDS:
Once we come to recognize the patterns of thrush and disease, and understand how the heel crack plays a crucial role, we will catch the warning signs far in advance. We will notice a heel that is becoming soft by noticing when our horse begins to shy away from rough terrain or overreacts to normal hoof cleaning. We will readily notice gate changes and temperament changes. In short, we will become proactive instead of reactive. This proactive attitude will save time and money. (A year’s worth of maintenance is far less expensive than an emergency call to the farrier or vet.)
Meanwhile we are now prepared with the facts when one of our peers say, “That heel crack isn’t a problem! Besides, it will never grow back.” Yet common sense – and the photos included in this story - tell us differently.
About the author:
Heath Kizzier is Vice President for Four Oaks Farm Ventures, Inc, the maker of No Thrush - The First Ever Dry Formula.