Hoof Wall Health

What health clues can you identify from looking at the hoof wall?

The hoof wall can tell you about hoof health and sometimes it can tell you about metabolic problems including laminitis. In this week’s blog I cover some common signs of hoof wall weakness and what each sign might indicate.

When you look at your horse’s hooves as viewed from the front, are the medial and lateral wall mirror images? Most horses do not have perfectly symmetrical feet. As you learned in the June 8th blog, pre-made horseshoes have distinct front and hind shapes but for each foot, the shoe is shaped symmetrically. Yet in reality most horses have slightly more upright medial wall compared to the lateral. The medial branch of the shoe usually needs to be shaped by the farrier to be straighter with the lateral branch a more rounded shape. This is normal but in some horses the difference between medial and lateral wall shape is excessive, leading to flares or cracks if the horn cannot withstand the asymmetrical forces. Feet can be somewhat asymmetrical and still have healthy wall horn. But feet that are markedly distorted tend to have weak walls.

Look closely at the texture and color of your horse’s hoof wall. In a healthy hoof the horn is smooth and may even be shiny. Run your fingers over the surface to check for subtle dishes or flares that may not be apparent at first glance. Hoof integrity can be compromised by loads that are too heavy, imbalanced, or both. For example, if a horse injures one foot or limb, the others must support more than their share of the load. This will predispose the supporting hooves to flare and dishing. If hoof wall is weak, despite good balance, the wall may crack, chip or flare equally around the bottom edge. If the wall is weak in addition to being off balance, more distortion will be apparent, such as asymmetrical dishing or flaring.

If hoof wall horn defects are present in all 4 feet there is likely to be a nutritional imbalance involved. When problems are isolated to one foot, it is more likely a postural cause.

A warning sign of internal dysfunction is growth rings on the hoof wall. Sometimes called “fever rings,” they indicate injury or systemic stress. Hoof wall is generated at the coronet and grows downward, usually at a rate of ¼- ½ inch per month in healthy horses. You can estimate when stress occurred by measuring the distance from the coronet to the growth ring. You may see just one ring, or a few rings close together with the rest of the hoof wall smooth. This may indicate a transient stress (such as extreme weather, a dietary change, a stressful trailer ride or competition weekend). The rings form when there is a disturbance to the blood supply that upsets the normal smooth production of new horn cells. A passing event is nothing to worry about.

But if the rings are always present and take up the whole wall from coronet to ground, something is wrong! It means your horse is experiencing altered blood supply to the foot. Look closely at adjacent rings from the mid-line at the toe around until they disappear at the heel. If the rings are parallel to each other all the way around the hoof’s circumference it usually means the feet are well balanced but they are still undergoing some stress. Your veterinarian and farrier may need to collaborate in helping you identify hoof versus horse health factors involved.

If the space between the two rings diverges at the heel, this indicates that the heel has grown faster or worn slower than the toe. This type of wall distortion is common on feet with chronically high heels. You might see divergent growth rings on club feet but the most common cause is chronic laminitis and the rings are termed “founder rings”.

Any of these signs—flares, cracks or growth rings—generally indicate that the foot is experiencing forces it is not strong enough to bear. If you can identify the underlying cause of a wall abnormality you may find things you can alter in your horse’s hoof care, training regimen or nutritional program that will improve hoof wall horn integrity.

Copyright © 2012 ~ Dr. Lisa Lancaster DVM, WDAA Blog Author