Solve Hoof Health Problems

Help your horse put his best feet forward.

By Natalie DeFee Mendik | January 30, 2015

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Some horses are blessed with good, strong feet. While their owners can thank their lucky stars, others have horses with less-than-stellar hooves and know the problems that can bring.
What steps can you take to get the best hooves possible, and what are some common hoof problems you may face? Vernon Dryden, DVM and certified journeyman farrier of Rood & Riddle Equine Hospital in Lexington, Ky., answers these questions and shares some expert advice for dealing with hoof woes, from thrush-busting to abscess blues.

Diligence
The easiest yet most critical component of your hoof-care tool kit is to pay attention and stay on the ball. Regularly pick out your horse’s feet, checking for any abnormalities such as loose clinches or sprung shoes on shod horses, heat, cracks or thrush. "Be aware, be a good all-around horseman, and be cognizant of different hoof abnormalities,” says Dryden.
Next up is good housekeeping. Avoid exposing your horse to excessively wet, muddy or rocky conditions. "Keep the horse in a good environment,” recommends Dryden. "You can’t expect a horse to thrive in mud, feces and urine, or a rocky field.”
While exposure to rocky terrain can lead to bruising and abscesses, increased bacterial growth from wet and muddy conditions can result in ailments like thrush and white line disease. In addition, wet-dry cycles can cause the hoof to expand and contract, causing cracks and loosening clinches.
Like Clockwork
Quality, regular farriery is paramount to good hooves. "The best thing a horse owner can do is to identify a qualified farrier to regularly trim or shoe their horse’s feet on a four- to six-week shoeing or trimming cycle to maintain a nice, solid foot,” notes Dryden. Farrier care is not a place to pinch pennies. Don’t try to stretch out a shoeing cycle, and don’t settle for the lowest bidder just to save a buck. You will get what you pay for.

What about Barefoot? In the right environment, going barefoot can be an appealing option. A horse with good feet that works in a discipline where shoes are not required can be a candidate for bare feet. A forgiving stall surface and non-rocky, nonabrasive riding footing are crucial for avoiding wear and tear and bruising. Hoof boots can help in circumstances where a barefoot horse needs extra protection. For a horse that is already shod, transitioning to barefoot should be a gradual process; use hoof boots as needed while he slowly builds up to going barefoot. Farrier visits are still important; regular trimming maintains correct hoof conformation, ensuring the structures are loaded correctly.

When looking for a horseshoer, remember that there are no mandatory licensing requirements in the U.S. to practice farriery. Voluntary certification programs, however, attest to a shoer’s knowledge, experience and skill. Look for a professional with credentials from a program such as those offered by the American Farriers Association. Also look for satisfied clients who are willing to serve as references. Word of mouth goes a long way as well: ask for recommendations among your network of equine contacts. From the Inside Out
If your horse isn’t graced with optimal hooves, you may want to consider a hoof supplement. While proper nutrition always comes first, a quality supplement can be helpful if your horse is still lacking in good, strong hoof growth.
"If a horse is deficient in a trace mineral or an amino acid that is important for developing hooves normally, then supplements may be beneficial,” says Dryden. "I think hoof supplements definitely have a place, and I use them on cases that I feel may not be getting as much nutritional value as they should.” He recommends a supplement containing biotin and methionine, which are thought to bolster hoof resiliency and aid in growth.
Along with supplements, hoof dressings have a place in the hoof-care arsenal. "Topical hoof treatments depend on the environment and the quality of the foot,” explains Dryden. "If the horse has very dry, flaky hooves, it may be best to apply a moisturizing topical. If the horse has extremely soft feet that aren’t holding together well, it may be beneficial to apply a hardening topical, like Keratex, to maintain more rigidity.”
Hot Spots
Even with great care, horses can face their share of hoof ailments. Here are some common issues you might face.
Thrush: Everyone has experienced the stinky smell of thrushy feet, but did you know that untreated thrush could actually lead to lameness? Thrush is caused by anaerobic bacteria invading the frog tissue from the sulci (grooves alongside the frog), and is characterized by a foul-smelling, black-colored sludge. Daily hoof cleaning can help keep thrush at bay, although other factors may come into play, such as full hoof pads or insufficient exercise, both of which reduce the hoof’s natural ability to shed debris. Upright hoof conformation with deep frog sulci can also predispose a horse to thrush. Store-bought treatments applied according to the manufacturers’ or your veterinarian’s directions can help resolve thrush. However, regular hoof-picking and maintaining a clean environment for your horse are the best methods for preventing this hoof ailment.

Soaking a hoof to treat an abscess.

Abscesses: One day your horse is sound; the next day he’s extremely lame and may also have a bounding digital pulse in one foot, heat around the coronary band, and swelling up the pastern. This is a well-known scenario that usually indicates a hoof abscess, a relatively common occurrence involving a local infection and pus buildup within the hoof. If your horse is severely lame, call your vet first to discuss the issue; if she thinks it’s an abscess, in many cases it will resolve with treatment you can administer yourself.
Abscesses are often the result of hoof bruising or bacteria invading the hoof via a crack or misplaced nail from a recent shoeing. Luckily, abscess treatment tends to be pretty straightforward, usually involving draining the infected area, soaking, poulticing and hoof wrapping. However, if the abscess does not resolve in a couple of days, it may be necessary to get your veterinarian involved due to the possibility of the infection from the abscess invading a deeper structure, such as the coffin bone.
Chronic, low-grade laminitis: "Many horse owners don’t even realize that their horses have chronic, low-grade laminitis,” remarks Dryden. These horses are plagued by off-and-on mild lameness and may be older and categorized as metabolic, insulin-resistant, or Cushingoid (having Cushing’s disease). Using lab work and imaging diagnostics, your veterinarian can identify abnormalities and formulate a treatment plan encompassing dietary needs, medical management, exercise, grazing/turnout routine, and therapeutic shoeing options.
White line disease: Looking at the sole of your horse’s hoof, you can see the junction between the outside hoof wall and the sole, known as the white line. This white-shaded line runs the perimeter of the sole where it meets the hoof wall. Bacteria and fungus that cause white line disease are found everywhere in the environment. These microorganisms are typically anaerobic and consume the white line just inside of the hoof wall. This may lead to separation of the wall, instability of the hoof capsule, and even mechanical laminitis/coffin-bone rotation. Microorganisms typically find their way into the hoof via compromised areas of the white line, such as a weak and cracked hoof wall.
Your veterinarian and farrier will be able to determine the extent of the white line disease and formulate a plan for treatment. Often the diseased area of the hoof must be removed, then treated topically; your veterinarian can recommend products, which can range from a simple chlorine-based solution to commercial products such as White Lightning or CleanTrax. Preventing white line disease is far easier than treating it. Like thrush, white line disease may be circumvented by proper hoof care and good hygiene.
Regardless of whether your horse experiences these hoof problems or one of the many others out there, a skilled vet and farrier team, along with timely intervention, is essential to his well-being.
A little effort goes a long way. "Pick out and care for your horse’s feet daily,” says Dryden. "Take note of patterns and changes. And most importantly, invest in routine farrier care with a qualified individual.” Stay on top of things; you’ll know if your horse’s hoof care is working when he’s sound, even and balanced.

Hoof Anatomy, The Outer Structures

When you look at the hoof as the horse stands, you are seeing the hoof wall. If you pick up the hoof to look at the bottom, you will see the sole, frog, sulci, heels and bar.

Photo: Alexandra Beckstett, The Horse Managing Editor

The hoof's external health affects the bones and soft tissues within, and vice versa

Many horse owners go their whole lives caring for horses’ hooves with little knowledge of the hoof capsules’ inner workings—the interaction of the bones, tendons, ligaments, and other parts that lie beneath. They might be aware of how the hoof’s outer condition reflects its external health, but the hoof’s appearance also provides a wealth of information on its internal well-being. It’s much more than just a covering for the end of the limb or the equine equivalent of the human fingernail.

Long-term hoof imbalances put excess strain on the bones and soft tissues, potentially compromising the structures’ shape and sturdiness long-term. Conversely, damaged or misshapen internal structures can effect congruent changes in hoof shape.

In part 1 of this series we described internal hoof structures and common problems. Now we’ll put it all together by discussing external hoof anatomy, common problems, and how they relate to the internal structures. 

External Hoof Anatomy

When you look at the hoof as the horse stands, you are seeing the hoof wall. It grows down from the coronary band, the junction between the hoof and the skin. The toe is closest to the horse’s nose, the heels are closer to his tail, and the quarters are between.

If you pick up the hoof to look at the bottom, you will see the wall wrapping around the outer edge and the white line just inside of it (easier to see in a freshly trimmed foot). Moving rearward from the toe, you’ll find the sole that covers the majority of the hoof’s bottom. There is also a triangular elastic structure pointing forward from the heels called the frog (which aids in shock absorption). In the center of the frog and on either side are grooves called the central and lateral sulci. Lastly, we have the heels directly behind the frog and the bars at the rearward ends of the hoof wall, where the wall turns inward and then forward away from the heels. 

Most healthy hooves have the following characteristics, says Amy Rucker, DVM, owner of Midwest Equine, in Columbia, Missouri.

• Heavy (thick) hoof wall with wide, even growth rings from toe to heel.
• Significantly shorter heels than toes. 
• A white line that is tight and uniformly wide through the toe, then slightly narrower in the quarters.
• A heavy/thick (not flexible or overly sensitive) sole with some cup (not flat).
• A frog that is neither recessed up into the foot, with deep sulci, nor protruding down past the sole.
• Heel bulbs that are not contracted (narrow with a deep groove running into the central sulcus of the frog).

Also consider the following signs of hoof health: 

• When viewing the foot from the side, drop an imaginary vertical line down from the front of the coronary band to the ground. Two-thirds of the foot’s ground surface should be behind that line. Draw another imaginary line up from the rear edge of the heels where they touch the ground; it should intersect in the rear third of the coronary band (weak heels run further forward). 
• When viewed from the front, the coronary band should be parallel to the ground from left to right, sloping gently and evenly down from toe to heels.
• Hoof wall tubules (the “grain”) should go straight down the wall to the ground, not diverting left or right.
• The angle the heel makes with the ground should be similar to that of the toe, but it is often a few degrees less. 
• The hoof should be roughly as wide as it is long.
• The frog’s width should be 60-70% of its length, adds Stephen O’Grady, DVM, MRCVS, of Northern Virginia Equine. 

Hoof Evaluation

Aside from looking for obvious injury, “Visual examination of the foot—its growth pattern, shape, and external characteristics—hints at internal areas of the foot that bear more ‘load’ or stress (and, thus, need unloading),” explains Rucker.

Increased stresses on parts of the hoof can have three results: 

1. Wall deviation or bending (flaring outward or rolling/running under);
2. Pushing up of the coronary band; and/or
3. Decreased hoof wall growth, evidenced by growth rings that are closer together in a stressed area, O’Grady says.

The hoof doesn’t exist in a vacuum, however—O’Grady encourages owners to also consider limb conformation, which can change how forces are distributed within the hoof capsule, leading to hoof wall deformation. 

Common Hoof Problems

Let’s start with the problems that involve damage and disease of outer structures, then we’ll move on to problems related to hoof balance.

With puncture wounds from stepping on a nail or similar sharp object, the real risk isn’t the hole, but the expressway it provides for bacteria to get deep inside the body and cause infection. Rucker strongly recommends leaving the object in place if possible until the veterinarian can radiograph (X ray) the foot to see what internal structures are affected. 

Scarring from coronary band damage can cause altered hoof growth below the injured area for the rest of the horse’s life. 

“These injuries need to be bandaged and treated to restore alignment of hoof tubules for healthy future growth,” Rucker advises.

“Visual examination of the foot hints at internal areas of the foot that bear more load or stress.”

Dr. Amy Rucker

Minor chips, cracks, and missing chunks of wall might be nothing to sweat over, but more serious damage such as deep quarter cracks and large missing pieces of hoof can be much more painful and problematic.

“If you have a large chunk of the hoof missing with bleeding, have a vet out because the horse may need a pressure wrap to keep the wall from bulging and regrowing incorrectly,” says Rucker. “The vet can also radiograph quarter crack cases to help the farrier treat them,” based on any internal damage that might have happened.

Abscesses are pockets of infection (like pimples) that can break open at the thinner coronary band area or rupture through the sole/white line. Once the abscess bursts, lameness improves immediately because of the reduced pressure. 

“Anytime a horse is non-weight-bearing lame, I worry about a fracture or septic (infected) tendon, but it’s usually an abscess,” says Rucker. “They’re horribly painful, and (a non-steroidal anti-inflammatory such as) phenylbutazone (Bute) won’t resolve the pain.”

White line disease is an opportunistic fungal or bacterial infection that strikes where the wall is already stressed or cracked, softening the inner hoof wall so it crumbles and allows outer wall layers to detach. 

“You have to remove enough wall to get air to affected areas (to help kill the microbes breaking the wall down), support the remaining foot with a special shoe, and lay the horse off while the wall regrows,” says Rucker. 

Thrush, a bacterial infection of the frog and sulci, can be caused by a dirty/wet environment, says Rucker. But that’s not always the case; other causes include anything that impairs the horse’s natural hoof-cleaning mechanism—continuous changes in the hoof’s inner structure, aided by movement, that keep the horse’s foot clean. “Keep affected feet dry and clean and the frog trimmed so you can get air and medications down into the sulci,” she says. 

Now let’s move on to hoof problems tied to the internal structures. In most mild cases, Rucker notes, the horse can return to soundness, but the more severe the problem, the greater the chances it will become long-term.

Club feet, caused by overly tight deep digital flexor tendons, have a steep toe angle and often a more horizontal coronary band when viewed from the side. The hoof-pastern axis is broken forward (hoof steeper than pastern), and the hoof might flare at the toe as a result of the tendon pulling the toe of the coffin bone down and rearward.

These features are similar to what’s seen when the coffin bone has become unstable and rotated downward at the toe from chronic laminitis, O’Grady adds. Both club footed and laminitis-affected horses exhibit a high palmar angle (heels of the coffin bone are significantly higher than the toe).

“If the white line is stretched at the toe, the case is more severe,” Rucker notes. “If radiographs show bone damage from the increased pressure on the toe, it’s harder to keep these horses sound.”

Long toe/low heel is the opposite of a club foot; if the hoof-pastern angle is broken back, the horse probably has a long toe and low heel. The long toe puts a lot of leverage on the heels, crushing them even to the point that the hoof tubules are horizontal (parallel with the ground). Horses with such heel conformation typically have a poorly developed digital cushion and thin collateral cartilages, says O’Grady. 

Rucker adds that affected horses usually have a negative palmar angle, heel pain, and might develop navicular and coffin joint pain from the abnormal stress applied to those structures. 

Sheared heels occur when the coronary band is higher in one quarter/heel area of the hoof than the other, says O’Grady. This can result from compressive stress (the wall could be too long in that area) and is frequently accompanied by narrowed growth rings. The higher heel is also more prone to vertical quarter cracks.  

Contracted heels occur along with a compromised digital cushion and, therefore, reduced shock absorption.

Thin soles can be caused by genetics and/or overtrimming. Rucker explains that horses with thin-soled feet often have flat soles (no cup) and an overly thin wall. “These feet often have nail holes and growth rings close together because the foot just isn’t growing well,” she comments. 

Laminitis, if severe or chronic, can alter hoof growth. O’Grady explains that chronically laminitic feet usually have wider growth rings at the heel than at the toe (because the damage tends to be worse at the toe, compromising growth there more severely than at the heels).

Rucker adds that the dorsal wall and white line can widen at the toe as the attachment of the hoof to internal structures collapses and the hoof tubules begin to grow outward. 

Take-Home Message

Keep your horses sound by watching their feet for small changes on the outside that could indicate problems are brewing on the inside. Prevention or early detection are far simpler, cheaper, and more effective than treating lameness or injury.

“Understand the challenges of each limb and hoof’s conformation and manage the foot for maximum soundness with that conformation rather than conforming to a ‘perfect’ standard,” says Rucker. “Everyone tries to get their horses’ feet to look pretty and perfect, when having functional feet with plenty of mass is much more important than having pretty feet. (With the latter) the owner is happy, but the horse isn’t.”