Understanding and overcoming 7 common equine foot issues

Sometimes a severe, career-altering injury or pathology, such as a deep digital flexor tendon (DDFT) tear or coffin joint arthritis, causes your horse’s foot lameness. In other instances, usually less serious, the outer hoof structures themselves create the gimpy gait. Learning to recognize, treat, and prevent these (mostly) avoidable conditions not only spares your horse unnecessary discomfort but also helps you avoid lost riding time and incurring veterinary expenses. After all, you’d be the one footing the bill for your horse’s hoof problems.

To get some answers about seven common hoof capsule conditions, we’ve recruited two experts from the Virginia-Maryland College of Veterinary Medicine, in Blacksburg, Virginia: Lauren Trager, DVM, MS, Dipl. ACVSMR, clinical assistant professor of equine sports medicine and rehabilitation, and Travis Burns, MSc, CJF, TE, EE, FWCF, associate professor of practice and the chief of farrier services at the veterinary school.

Promoting Healthy Hooves

As an owner, you must work with the cards you are dealt—the feet that came with your horse. But unlike a conformation fault that’s set in stone, there’s a lot you can do with nutrition, management, and farriery to protect less-than-perfect hooves from the myriad issues we’ll discuss in this article. With all 1,200-plus pounds of your horse resting on the size equivalent of four upside-down saucers, it’s only natural you’d want to take the absolute best care of his hooves.

Starting with the basics, a balanced diet with adequate protein plays a crucial role in hoof growth and quality because the hoof wall consists mainly of a protein called keratin. Feeding enough biotin (vitamin B7)—the single most important vitamin for hoof health—also remains a top priority. Be patient with dietary adjustments and stick to the plan you have devised with your equine nutritionist or veterinarian, keeping in mind it can take up to a year for a horse to grow a whole new hoof.

Proper hygiene pays dividends in keeping hooves healthy and intact. Bed your horse’s stall well (a minimum of 4 inches in depth) and clean it at least daily, limit mud exposure, and pick his feet regularly—especially if he wears shoes, which can trap moisture and debris. Last, but certainly not least, regular hoof care by a skilled farrier can help prevent unbalanced, overgrown, or cracked hooves that open the door—or rather, the wall—to abscesses and other issues.

The Recipe for Hoof Problems

Despite the hoof’s tough, impermeable appearance, it functions as a living, breathing organ that responds and adapts to its environment. Unfavorable genetics, nutritional deficiencies, unsanitary living conditions, and lack of quality hoof care all contribute as risk factors for poor hoof health.

Specifically, prolonged exposure to water—such as standing in deep mud all day—or, on the contrary, excessive dryness—both weaken the horse’s hoof horn¹. “Research² shows that contact with manure and urine-soaked bedding also weakens the hoof wall and introduces bacteria and fungi into the frog and white line, compromising the health and integrity of the hoof capsule,” Burns says.

We’ve categorized hoof capsule ailments into seven distinct conditions: subsolar abscess, hoof bruise, hoof crack, white line disease, thrush, canker, and supporting-limb laminitis.

1. Subsolar Abscess

If you’ve ever found your horse suddenly three-legged lame, with a hot hoof and a bounding digital pulse, you’ve probably feared the worst—a fracture—and held your breath until a pocket of pus finally blew out the bottom of his foot. Subsolar—meaning under the sole—abscesses in horses are essentially just large pimples. But because these pockets of pus and debris remain tightly compressed inside the hoof capsule, unable to swell and expand outward like they would on the skin, they cause extreme pain. (Imagine having a pimple stuck under your nail. Ouch!) Putting weight on the abscessed tissue aggravates the pain and often causes a degree of lameness that frightens the horse’s caretakers.

“Despite the crippling pain they can cause, abscesses are generally only serious if they are not treated but instead allowed to undermine the hoof capsule for a prolonged period of time,” Burns says. “This creates the potential for the infection to spread to other parts of the foot.

In an ideal world, the farrier or vet locates and opens the abscess at the margin of the sole through the white line.

“This allows for faster healing than an abscess that ‘blows’ or erupts at the coronary band (where the hairline meets the hoof capsule), leaving a horizontal hoof crack that can take several months to grow out,” says Burns.

Soaking the hoof to soften it and packing it with drawing agents encourages a suspected abscess to emerge. Across various barns you’ll encounter different concoctions, often featuring Epsom salts and the drawing salve ichthammol. Some people also add the antiseptic povidone-iodine (Betadine) to kill bacteria. “A hoof abscess is an infection,” says Burns. “The pus, an agglomeration of dirt, debris, and microbes, invades the foot.”

But the traditional “soak, pack, then wait” method isn’t always the most effective or practical, experts say. “Most of the drawing agents do not work well on the hoof,” Burns says, reflecting on his experience. “In my opinion, if a horse owner has a suspected abscess, they should call their vet or farrier right away. Using hoof testers and a hoof knife, either professional should be able to identify, localize, and open an abscess quickly to provide relief to the horse. Once the pus can drain, the pressure is released, and the horse should become at least somewhat more comfortable within 24 hours.”

Trager agrees. “In my opinion, soaking the foot doesn’t actually help an abscess mature,” she says, arguing that moisture can be undesirable. “Now, if the horse has an abscess that’s already opened and draining, then soaking can help that process. Otherwise, I don’t find it particularly useful.”

2. Hoof Bruise

Horses with naturally thin soles are prone to hoof bruising if they step on hard, rocky ground. Thin soles—and the solar bruising that can come with them—challenge many Thoroughbred owners, though the condition affects all horses, whether shod or barefoot. Depending on the amount of hemorrhage, blood might pool under the sole, causing red or purple discoloration. If your horse sustains a hoof bruise, expect him to show signs of lameness and sensitivity to pressure on his sole, frog, and/or heels.

Hoof pads or boots might be necessary to relieve the horse’s foot tenderness and guard the sole from further damage. “With solar bruises, my first plan of action is typically to protect the sole by incorporating a leather or plastic pad (when shoeing),” Burns explains. “I also use soft silicone or foam hoof packing underneath to pad the bruised areas.”

If that’s not enough, the farrier then turns to a metal plate for a more rigid protective cover. Solar bruises typically take weeks or months to heal, depending on their severity, the promptness and effectiveness of treatment, and the horse’s general hoof health.

3. Hoof Crack

Hooves split and crack when they are too dry³, weak, or brittle. Cracks can also occur from uneven pressure distribution across the weight-bearing surface because of an unbalanced trim or sheared (uneven) heels⁴, for example. Hoof cracks can be quite painful and cause lameness. “The most concerning cracks are vertical, complete (top to bottom), and full thickness—through all three layers of the hoof wall,” says Burns.

Farriers can repair hoof cracks with strategic trimming, shoeing, and literal patching. In the long run you can help keep your horse’s hooves in one piece by applying a hoof hardener (for weak, brittle horn) or a hoof moisturizer (for dry, cracking horn). Your veterinarian or farrier can help you select the best option for your case, taking the entire horse, his environment, and history into account.

4. White Line Disease

Also called “seedy toe,” white line disease in horses involves the separation of the hoof wall from the underlying laminae. Abnormal or uneven stress on the hoof wall, either from poor hoof conformation or, again, an unbalanced trim⁵, typically plays a role. Opportunistic bacteria and fungi can infiltrate the fissures of the wall, leading to an infection that eats away at the hoof.

Treating severe, advanced white line disease often means taking aggressive measures. Veterinarians might pursue debridement surgery, followed by packing topical antimicrobial medication and iodine or copper sulfate-soaked gauze pads into the surgical opening. In some cases the horse needs corrective shoeing to support and protect the hoof during the healing process.

5. Thrush

Horse owners commonly encounter thrush. In fact, you’ve probably seen—and smelled—thrush before you even knew what it was. Researchers have shown a mixed bag of bacteria causes the putrid black discharge coming from your horse’s frog and sole⁶.

“Risk factors for the development of thrush include wet, unsanitary conditions, lack of movement, infrequent hoof cleaning, but also less-than-ideal hoof conformation such as contracted heels or an atrophied frog,” says Burns. “Additionally, horses that wear pads without antimicrobial hoof packing are more at risk for thrush” due to the moist environment.

Treatment for thrush has evolved in recent years because scientists have determined the active ingredients in many topical products—namely formaldehyde and gentian violet—can be carcinogenic to the humans who handle them. Alternative treatments now include copper naphthenate, cephapirin benzathine, chlorhexidine, and iodine.

6. Canker

As for canker, Trager explains it’s an infection characterized by a chronic, hypertrophic, moist dermatitis reaction that affects horn-producing tissues. “While thrush and canker are two different diseases, both can affect the frog and arise under the same moist, unsanitary conditions,” she says. “Long-standing thrush has even been implicated as a cause of canker due to the damage and degeneration it causes to horn cells.” Considering this, a horse with thrush could be more susceptible to canker, the veterinarian concludes, pointing to the need for further research on the apparent correlation between the two.

7. Supporting-Limb Laminitis

Laminitis occurs when the laminae, responsible for suspending the coffin bone within the hoof capsule, suffer damage and inflammation. In severe cases they detach, allowing the coffin bone to rotate downward or sink.

It often stems from systemic issues such as a carbohydrate overload or a fever associated with a body-wide infection. Supporting-limb laminitis, a less common form of the condition, primarily affects the hoof capsule.

“Support-limb laminitis occurs when a horse overloads one foot to offload another painful one,” explains Trager. Take, for example, a horse that has sustained a fracture to his right-hind cannon bone. The left hind leg will carry extra weight to support and offload the painful right hind. This can sometimes go on 24/7 for weeks or even months on end. The renowned Thoroughbred racehorse Barbaro faced this exact misfortune when he succumbed to supporting-limb laminitis in 2007 after successful surgical repair of his fractures.

“Support-limb laminitis happens because of laminar injury from hypoxia (low oxygen levels) in response to vascular derangement within the limb,” Trager says, blaming lack of movement of the horse’s supporting limb for the vascular stasis (blood pooling) within the limb. 

Trager describes the disease process. “Due to the decreased blood flow, small blood clots form in the vessels, eventually leading to laminar hypoxia,” she says. “This oxygen deprivation can cause the lamellar apparatus to fail, and the coffin bone to rotate.” She notes that while the horse might not be systemically ill with supporting-limb laminitis, the vascular derangement that occurs can affect much more than just the hoof capsule.

Take-Home Message

In many cases you can spare your equine companion from painful, debilitating hoof capsule problems with balanced nutrition, clean living conditions, regular hoof picking, and skilled trimming or shoeing. Dutifully applying these simple concepts to your horse’s care and management lays the groundwork for strong, healthy, and resilient hooves.

References

1. Bertram JEA, Gosline JM. Functional design of horse hoof keratin: the modulation of mechanical properties through hydration effects. J Exp Biol. 1987;130(1):121–136.

2. Munzinger K, Monhart B, Geyer H. The Influence of Environmental Factors on the Hoof of Horses. Anatomia Histologia Embryologia. 2005;34(1):36.

3. Pütz AC. (2006). Monitoring of seasonal influences, the effect of housing conditions and domestication on the horn quality of the equine hoof. Freie Universität Berlin. tinyurl.com/ymdszvak

4. Beasley B. Hoof Cracks in Horses. Merck Veterinary Manual. 2024. tinyurl.com/2uxswhud

5. Beasley B. White Line Disease in Horses. Merck Veterinary Manual. 2024. tinyurl.com/3v884tnj

6. Pelletier M, Draper J. Characterization and identification of bacterial flora from infected equine hooves. International Journal of Veterinary Science and Research. 2022;8(2):50–56.