hoof conditions

What is laminitis (founder)

Laminitis is the most serious disease of the equine foot and is considered the second biggest killer of horses after colic.

Why do horses often die when they develop laminitis

Horses usually do not die from laminitis itself; catastrophic lameness caused by the damage often leads to euthanasia when treatment is unsuccessful.

Which feet are most commonly affected by laminitis

Laminitis can affect all four feet but is much more commonly observed in the front hooves.

What begins the disease process in laminitis

The disease begins when trigger factors damage the basement membrane that bonds the dermal and epidermal laminae together.

What happens when the basement membrane is damaged in laminitis

The attachment between the dermal and epidermal laminae becomes compromised.

What occurs if laminitis damage becomes severe

The basement membrane, capillaries, and laminae can be destroyed.

What happens when the laminae “unzip”

The laminae separate and the coffin bone detaches from the hoof capsule.

What do healthy laminae look like

Healthy laminae are interlocked and tightly bonded.

What happens to dermal and epidermal laminae during laminitis

They become damaged and separated.

What is displacement in laminitis

The coffin bone is no longer anchored to the hoof wall and moves within the hoof capsule.

What are the two forms of coffin bone displacement

Rotation and distal descent.

What is a major cause of laminitis

Most cases are manmade due to poor management and feed practices not aligned with equine physiology.

What type of diet commonly triggers laminitis

Diets high in starches and sugars.

How do high starch and sugar diets lead to laminitis

Ingestion of significant amounts of non-structural carbohydrates causes systemic inflammation in the horse that can lead to laminitis.

What is navicular syndrome or navicular disease

Lameness attributed to disorders of the navicular bone and surrounding tissues.

What did a traditional diagnosis of navicular disease imply

A progressive incurable disability that could eventually require euthanasia if the horse became too uncomfortable.

How was navicular disease traditionally diagnosed

A positive response to a nerve block of the foot and X-rays showing degenerative changes in the navicular bone.

What do navicular lesions on X-rays typically look like

Pitting or “lollipop-shaped” lesions in the navicular bone.

What is a limitation of diagnosing navicular disease using X-rays alone

A horse may have navicular bone changes but not be lame, while another may have normal X-rays but still be lame.

What terms do veterinarians now commonly use instead of navicular disease

Palmar heel pain, caudal heel syndrome, palmar foot pain, and podotrochlear syndrome.

What do the newer navicular terms describe

Lameness that appears to originate from the back of the foot.

What discovery helped improve understanding of navicular problems

MRI technology.

Why are MRIs useful in diagnosing navicular-related problems

They allow visualization of soft tissue damage and bone abnormalities that cannot be seen on traditional X-rays.

What types of problems can MRI investigations reveal in the hoof

Strain or rupture of the deep digital flexor tendon (DDFT), inflammation of the navicular bursa, lesions or inflammation of the impar or collateral ligaments, edema in the navicular bone, tiny bone chips, inflammation or arthritis of the coffin joint, and cartilage wear on the palmar surface of the navicular bone.

Why is MRI considered the gold standard for diagnosing some hoof problems

It can reveal soft tissue injuries that do not appear on X-rays or ultrasound.

What does a disrupted or lighter appearance of the deep digital flexor tendon on MRI indicate

Damage or a tear in the tendon.

What is palmar foot pain

Lameness that appears to originate from structures located at the back of the hoof.

What are common signs of palmar foot pain

Slow progressive lameness, sudden forelimb lameness, short choppy gait, worsening lameness on hard ground, stumbling, toe-first landing, sensitivity to hoof testers, relief from nerve block, shifting body weight frequently, and resting the foot on the toe.

What is a palmar digital nerve block

A procedure used to numb the foot below a certain point to determine whether the horse’s pain originates in the foot.

What does it indicate if lameness disappears after a palmar digital nerve block

The source of the pain is likely located within the foot.

Why are X-rays considered unreliable for diagnosing navicular disease alone

Changes in the navicular bone do not reliably correlate with lameness or specific diagnoses.

What conditions can X-rays still help detect in hoof diagnostics

Fractures of the coffin or navicular bone and mineralization of the deep digital flexor tendon.

What is the most reliable indicator of navicular disease on MRI

Excessive edema (fluid) within the navicular bone.

What causes edema in the navicular bone

Inflammation or trauma resulting from stresses placed on the navicular bone.

What can prolonged navicular damage lead to if untreated

Osteonecrosis or fibroplasia.

What is osteonecrosis

Bone damage caused by reduced blood flow.

What is fibroplasia in the navicular bone

Replacement of normal bone and marrow with fibrous tissue that weakens the bone.

What is canker in horses

An unusual condition affecting the frog, bars, and sole of the hoof caused by an anaerobic infection of the superficial epithelium.

Where are most cases of canker found geographically

The southeastern United States.

What does canker look like in the hoof

White or gray moist spongy tissue in the sulci region, often described as resembling wet cauliflower with cottage cheese-like exudate.

How is canker treated

Removal of abnormal tissue, keeping the hoof clean and dry, topical treatments such as metronidazole or benzyl peroxide, and waterproof bandaging.

What is thrush

A degeneration of the frog with a secondary anaerobic bacterial infection beginning in the central and collateral sulci.

What are the signs of thrush

Moist sulci containing black thick discharge with a foul odor and necrotic frog borders.

What conditions commonly lead to thrush

Poor hoof conformation or trimming, lack of exercise, and moist environments with poor hygiene.

How is thrush treated

Providing a dry clean environment and using astringent solutions such as copper sulfate or commercial hoof treatments containing chlorine dioxide.

What are hoof cracks

Common hoof wall defects that vary in severity and clinical significance.

How are simple hoof cracks treated

Adequate trimming and shoeing.

How are severe or unstable hoof cracks treated

Removal of affected tissue or stabilization with therapy to prevent or treat lameness, often repaired using acrylic.

What is a hoof abscess

A bacterial infection trapped between the sensitive laminae and the hoof wall or sole.

Why are hoof abscesses painful

Bacteria create pus that builds pressure inside the hoof.

How lame can horses become from hoof abscesses

Horses may reach a level 5 on the lameness scale and be completely non-weight bearing.

What is gravel in horses

An infection that enters the white line area of the hoof and is a type of abscess.

Where does the infection from gravel typically exit

The coronary band.

What is dew poisoning (equine pastern dermatitis)

A skin infection around the lower limbs caused by constant moisture and mechanical irritation.

What are other names for equine pastern dermatitis

Scratches and mud fever.

What causes equine pastern dermatitis

Moisture and irritation damage the skin, allowing bacteria and fungi to enter through small cracks.

What are the symptoms of equine pastern dermatitis

Thickened, crusted, and painful skin around the lower limb.

How is equine pastern dermatitis treated

Topical treatments, veterinary care if necessary, antibiotics, and steroid ointments.