Bit & Bridle

Equine Hoof Cracks

Other Names

  • Hoof fissures
  • Hoof splits
  • Sand cracks
  • Grass cracks
  • Quarter cracks
  • Toe cracks

What are Hoof Cracks in Horses?

Hoof cracks are splits or fissures in the hoof wall — the hard, keratinised outer shell that encases and protects the sensitive internal structures of the foot. They are one of the most common hoof problems encountered in horses and can range from superficial surface blemishes that cause no discomfort, to deep structural fissures that result in significant lameness, pain, and secondary infection.

The hoof wall grows continuously downward from the coronary band (the band of tissue at the top of the hoof), at a rate of roughly 6–10mm per month. When this growth is disrupted — whether through nutritional imbalance, trauma, or improper farriery — the structural integrity of the wall can be compromised, creating conditions that allow cracks to develop.

Hoof cracks are classified by their location and depth. By location, they may be described as toe cracks, quarter cracks, or heel cracks. By depth, they are either superficial (affecting only the outer layers of the wall) or full-thickness (extending through the entire wall into sensitive tissue). Full-thickness cracks are far more serious and require immediate veterinary and farriery attention. Learn more about equine hoof anatomy in our horse terminology guide.

What Causes Hoof Cracks in Horses?

Hoof cracks rarely have a single cause. Most develop as a result of several contributing factors acting together:

  • Poor farriery: Infrequent trimming, improper balance, or incorrect shoe fit all place uneven mechanical stress on the hoof wall, making it more prone to splitting. A horse left too long between farrier visits will develop imbalanced feet that crack under load.
  • Nutritional deficiencies: The hoof wall is made primarily of keratin, a protein that requires adequate biotin, methionine, zinc, and other nutrients for healthy formation. Horses on poor diets or with metabolic conditions that affect nutrient absorption are particularly vulnerable.
  • Environmental conditions: Alternating wet and dry conditions are a major cause of hoof cracks. Hooves that repeatedly absorb moisture and then dry out become brittle and prone to fissuring. Horses kept on very hard, abrasive ground or in consistently wet conditions are both at higher risk.
  • Trauma: A direct blow to the hoof wall — from a kick, a sharp stone, or an awkward landing — can initiate a crack, particularly if the hoof wall is already compromised.
  • Conformation issues: Horses with flared feet, club feet, or other conformational abnormalities distribute load unevenly, creating zones of high stress that are susceptible to cracking.
  • Underlying hoof disease: Conditions such as white line disease or thrush weaken the internal structure of the hoof wall, making surface cracks more likely and more serious when they do occur.
  • Genetics: Some breeds, particularly those with naturally fine or flat hooves, are more prone to cracking. Thoroughbreds and warmbloods are commonly affected compared to native breeds with denser hoof horn.

Signs and Symptoms of Hoof Cracks

The signs of hoof cracks vary significantly depending on their depth and location:

  • Visible fissure: The most obvious sign — a crack running vertically (most common), horizontally, or at an angle along the hoof wall.
  • Lameness: Present in moderate to severe cases, particularly with quarter cracks, which occur in the side of the hoof where the wall is thinnest and most load-bearing.
  • Blood or discharge: Deep cracks that extend into sensitive laminae may show blood, serum, or pus at the base of the crack — a sign of infection.
  • Hoof wall movement: In unstable cracks, the two edges of the crack may move independently as the horse bears weight, causing pinching of underlying tissue and significant pain.
  • Heat in the hoof: Increased warmth around the crack suggests inflammation or infection in the deeper structures.

Diagnosis

Diagnosis is largely visual, but a thorough assessment requires more than simply spotting the crack. Your farrier or vet will evaluate the crack’s depth, location, direction, and stability. Hoof testers may be used to identify pain responses, and the horse should be observed in motion to assess the degree of lameness. In cases where infection or deep structural involvement is suspected, X-rays (radiographs) may be taken to assess the coffin bone and internal hoof structures. Radiography is also useful for planning surgical shoeing interventions.

Treatment of Hoof Cracks in Horses

Treatment depends entirely on the severity of the crack:

  • Superficial cracks: These often resolve with consistent, correct farriery. The farrier may notch or groove the top of the crack to prevent it from extending upward, and regular trimming will gradually grow out the damaged section.
  • Moderate cracks: May require hoof boots or bandaging to protect the area and stabilise the wall while healing occurs. Topical hoof conditioners can help maintain appropriate moisture balance.
  • Full-thickness and unstable cracks: These require specialist farriery. Techniques include the application of hoof patches (fibreglass or acrylic composites), lacing or wiring the crack edges together, and corrective shoeing with bar shoes or clips to redistribute load away from the affected area. Any infection within the crack must be debrided and treated before patching.
  • Infected cracks: If infection is present, the affected tissue must be cleaned out, and a course of antibiotics may be prescribed by your vet. Topical antiseptics may also be applied.

Recovery timelines vary. A superficial crack may grow out within a few months with good farriery, while a deep quarter crack in a performance horse may take the better part of a year to fully resolve, particularly if the horse needs to remain in work.

Prevention of Hoof Cracks

Consistent management is the most effective prevention strategy:

  • Regular farriery: Most horses should be trimmed or re-shod every 6–8 weeks. Irregular intervals allow hooves to grow imbalanced, increasing crack risk substantially.
  • Balanced nutrition: Ensure the diet provides adequate biotin (3–5mg/day is commonly supplemented in crack-prone horses), zinc, methionine, and good-quality protein. Feed a comprehensive hoof supplement if the horse is on a forage-only diet.
  • Manage environmental moisture: Avoid leaving horses standing in wet bedding or muddy gateways for extended periods. If the environment is very dry and hard, topical hoof moisturisers can help maintain wall flexibility.
  • Prompt treatment of hoof disease: Deal with white line disease and thrush promptly before they weaken hoof wall integrity.
  • Monitor conformation: Work with your farrier to identify and correct conformational imbalances before they cause cracking.

Prognosis

The prognosis for most hoof cracks is good with appropriate management. Superficial cracks carry an excellent prognosis and typically cause no long-term issues. Deep quarter cracks in performance horses carry a more guarded prognosis — while many horses return to full work, some will be prone to recurrence, particularly if underlying conformation or nutritional issues are not addressed. Full-thickness cracks that have become infected carry additional risk if the coffin bone or sensitive laminae are involved.

When to Call the Vet

Call your vet if you notice any of the following:

  • Lameness associated with a hoof crack
  • Blood, discharge, or pus at the site of the crack
  • A crack that appears to be deepening or widening rapidly
  • Heat and swelling in the lower limb
  • A horizontal crack (blow-out), which can indicate previous trauma to the coronary band

In these cases, your farrier and vet should assess together. Early intervention prevents minor cracks from becoming major structural problems.

Frequently Asked Questions

Can a horse work with a hoof crack?

It depends on the severity. Horses with superficial cracks can usually remain in light to moderate work. Horses with deep, infected, or unstable quarter cracks should be rested until the crack is stabilised by a farrier. Continuing to work a horse with an unstable crack risks worsening the injury and introducing infection. Always get your farrier’s assessment before continuing work.

How long does it take a hoof crack to grow out?

The hoof wall grows approximately 6–10mm per month from the coronary band to the ground. A crack at mid-wall may take 3–6 months to grow out; a crack originating at the coronary band may take 9–12 months to fully resolve. Regular trimming, good nutrition, and stable environmental conditions all support faster, healthier hoof growth.

Do hoof supplements actually help?

Yes, in horses with nutritional deficiencies, biotin supplementation in particular has strong evidence behind it. Studies have shown that daily biotin supplementation (at least 15–20mg/day for an average-sized horse) improves hoof horn quality and reduces cracking in horses with poor-quality feet. Results take time — allow 6–9 months to judge effectiveness, as supplements only affect new growth.

Why does my horse keep getting the same crack in the same place?

Recurring cracks in the same location usually point to an underlying mechanical issue — uneven weight distribution due to poor conformation, asymmetric trimming, or a previous injury to the coronary band that causes a permanent growth defect. A thorough farriery assessment, and potentially a veterinary lameness evaluation with radiographs, is worthwhile to identify the root cause.