Farrier & Hoof Care Glossary

A pocket of infection — usually bacterial — trapped between the sensitive and insensitive structures of the hoof. Typically causes sudden, severe lameness with localized heat and a strong digital pulse. Treated by draining the abscess through the sole or by allowing it to rupture naturally at the coronary band or heel bulb. One of the most common causes of acute, non-weight-bearing lameness.

Tiny tubular spaces within the hoof wall horn that run from the coronary band to the ground surface. They contribute to the hoof wall's ability to absorb moisture and provide some shock absorption.

A deviation of the limb when viewed from the front or back — the leg does not track straight. Valgus is an outward deviation (knock-kneed); varus is an inward deviation (bow-legged). Common in newborn foals, many of which self-correct. Persistent deformities may require corrective trimming, shoeing, or surgery before growth plates close.

The fusion of a joint through bone proliferation. In horses, most commonly associated with ringbone. Once the coffin or pastern joint fuses completely, movement through that joint stops — which paradoxically can relieve pain, allowing some horses to return to limited soundness.

The steel working surface on which a farrier shapes hot shoes. A good anvil rings clearly when struck (indicating dense, high-quality steel) and has a flat face (table), a rounded horn for bending, and various heel and step configurations. Weight typically ranges from 100 to 300 lbs for a farrier's working anvil.

Ringbone that involves the joint surface itself — the coffin joint (low articular ringbone) or pastern joint (high articular ringbone). More serious than periarticular ringbone because it directly affects joint cartilage. Often causes persistent lameness and is less likely to ankylose into soundness than non-articular forms.

A hoof where the medial (inside) and lateral (outside) walls are unequal in length or angle. Some degree of asymmetry is normal and desirable — the medial wall is typically slightly higher — but significant asymmetry contributes to joint stress and is addressed through corrective trimming.

Wasting or reduction in size of the frog and underlying digital cushion, typically from lack of ground contact and movement. Seen in horses kept on deep, soft footing or shod with pads that prevent frog contact. Reduces the heel's shock-absorbing capacity and is a risk factor for navicular syndrome.

The primary professional organization for farriers in the United States. Offers a tiered certification system — Farrier (CF), Journeyman Farrier (CJF), and Therapeutic Endorsement — that requires written exams, practical shoeing evaluations, and ongoing continuing education. AFA certification is a recognized baseline of competency.

The inward fold of the hoof wall at the heel that runs along the sides of the frog toward the toe. Bars help the hoof resist contraction and provide additional bearing surface. Excessive bar growth can fold over the sole and cause pressure; overly aggressive removal weakens the heel.

A shoe with a bar of metal connecting the two branches across the heels — either straight or curved. Provides additional heel support and stability, prevents the shoe from shifting, and can be used to bear on the frog. Types include straight bar, egg bar, and heart bar shoes.

The ground-facing surface of the hoof wall — the part that bears the horse's weight and contacts the shoe or ground directly. Proper bearing surface levelness and balance is the primary objective of trimming.

A B-complex vitamin (B7) that plays a role in keratin synthesis. Multiple controlled studies support its use at 20mg/day or more for improving hoof wall hardness and reducing cracking in horses with poor hoof quality. Results take 9–12 months to fully manifest, as the entire hoof must grow out. The most evidence-backed hoof supplement available.

The hoof has a rich blood supply via the digital arteries and their extensive branching within the sensitive laminae, solar corium, and coronary band. The frog mechanism — where frog contact compresses the digital cushion — actively pumps blood back up the leg. Disruption of this blood flow (as in laminitis) causes rapid, serious damage.

A tungsten carbide compound welded onto the shoe surface to provide permanent, extremely durable traction. Used on working horses on pavement, icy surfaces, or rough terrain where studs or road nails would wear too quickly. Unlike removable studs, borium is permanent and wears very slowly.

The moment during the stride when the heel lifts and the hoof pivots over the toe before leaving the ground. The point of breakover is the exact spot on the toe where this pivot occurs. Manipulating breakover (via rolled toes, rocker shoes, or set-back shoes) is a primary tool in corrective and therapeutic shoeing — easing breakover reduces stress on the DDFT, navicular structures, and coffin joint.

Hemorrhage and inflammation of the solar corium from impact — stepping on a stone, rock, or other hard object. Appears as reddish or purple discoloration visible when the sole is pared. Causes lameness ranging from subtle to severe. Common in Thoroughbreds and other horses with flat, thin soles. Prevented by sole protection — pads, pour-in materials, or appropriate shoes.

A chronic, progressive infection of the frog and solar corium resulting in abnormal, hypertrophied (overgrown) horn tissue. Appears as cauliflower-like white or gray proliferating mass at the frog, bleeds easily, and has a distinctive foul odor. Far more serious than thrush — invades sensitive tissue. Requires aggressive veterinary and farrier debridement followed by weeks of bandaging. Draft breeds are disproportionately affected.

The bent-over tip of a horseshoe nail that emerges through the outer hoof wall after nailing. The farrier cuts, smooths, and bends the clinch tight against the wall to lock the shoe in place. Protruding or risen clinches are sharp and can cause injury — a sign the shoe needs attention.

A chisel-like tool used to cut clinches before shoe removal. Placed under the clinch and struck with a hammer to sever the bent nail tip from the wall. Attempting to pull a shoe without first cutting clinches tears chunks of hoof wall.

The main bone within the hoof capsule, shaped to mirror the hoof's internal contour. Attached to the hoof wall via the sensitive and insensitive laminae. In laminitis, the coffin bone may rotate (tip downward at the toe) or sink (drop vertically within the capsule) — both are serious and potentially life-threatening. Visible on radiograph.

The joint between the short pastern bone (P2) and the coffin bone (P3), located inside the hoof capsule. The site of low ringbone, some navicular syndrome involvement, and coffin joint arthritis. Injected therapeutically when joint pain is identified. The joint also contains the navicular bone as a sesamoid.

Fitting and nailing a shoe without first heating it in a forge. The shoe may be bent slightly with tools but is not hot-shaped on the anvil. Faster and requires less equipment than hot shoeing but produces a less precise fit, particularly for horses with unusual hoof shapes or corrective needs.

The arch or dome of the sole — the degree to which the sole is cupped upward rather than flat. A well-developed concavity protects the sole from ground contact. Flat soles (insufficient concavity) are prone to bruising and pressure. Concavity varies significantly by breed — Arabians typically have more; Thoroughbreds often have less.

A condition where the heels of the hoof narrow inward, compressing the frog and reducing the hoof's natural expansion mechanism. The frog appears narrow and deep-seated. Causes include prolonged shoeing without frog contact, long-toe/low-heel syndrome, stall confinement, and some hereditary tendencies. Treated with corrective trimming and increased movement over varied terrain.

A trace mineral essential for cross-linking of keratin proteins — the chemical bonds that make hoof wall hard and strong. Deficiency (often caused by high dietary iron suppressing absorption) produces brittle, cracking hooves, faded coat color, and slow growth. Works synergistically with zinc; the two are always balanced together. Target: ~125 mg/day in a 4:1 zinc-to-copper ratio.

The soft, slightly swollen band of tissue at the top of the hoof capsule where new hoof wall originates and grows downward. The coronary band contains the coronary corium — the tissue that produces horn cells. Injuries to the coronary band can permanently disrupt hoof wall growth, producing permanent ridges, cracks, or defects. Gentle daily massage promotes circulation and healthy growth.

The use of modified shoe shapes, sizes, placement, pads, or additions to address specific biomechanical problems — conformational flaws, gait defects, lameness conditions, or injury. Distinguished from routine shoeing by its therapeutic intent. Requires a farrier with strong understanding of equine biomechanics, ideally working in coordination with a veterinarian.

The sensitive, vascular tissue beneath the hoof capsule that produces horn. Different regions: coronary corium (produces hoof wall), lamellar corium (produces sensitive laminae), solar corium (produces sole), frog corium (produces frog), and perioplic corium (produces the periople at the top of the wall). Damage to corium causes permanent changes to the horn it produces.

A split in the hoof wall, classified by origin and location. Grass cracks start at the ground and grow upward — usually from long toes or dry conditions. Sand cracks start at the coronary band and grow down — more serious, often from coronary band injury. Quarter cracks are vertical splits in the side wall from concussion or imbalance. Severity ranges from cosmetic to career-threatening.

A hormonal disorder caused by dysfunction of the pituitary gland, most common in horses over 15. Produces elevated ACTH and cortisol, leading to a range of signs including a long, curly coat that doesn't shed, muscle wasting, increased thirst and urination, and — critically — increased laminitis susceptibility. Managed with pergolide (Prascend). Every horse with recurring laminitis should be tested for PPID.

The tendon that runs down the back of the lower limb, wraps around the navicular bone, and attaches to the bottom of the coffin bone. Excessive tension in the DDFT — from long toes, low heels, or navicular changes — is a primary cause of palmar foot pain. In laminitis, the rotating coffin bone pulls away from the DDFT's attachment point. Managing DDFT tension through breakover and heel height is central to many corrective shoeing approaches.

The removal of infected, dead, or diseased tissue from a hoof condition. Performed by a farrier or veterinarian with a hoof knife. Required for abscesses, white line disease, canker, and some abscess sequelae. Adequate debridement — removing all diseased tissue even if it looks drastic — is essential for resolution. Incomplete debridement allows conditions to persist or recur.

A fibrocartilaginous pad that occupies the heel area of the hoof above the frog, between the lateral cartilages. Functions as the primary shock absorber of the hoof mechanism. Develops with use — horses with regular movement on varied terrain develop larger, firmer digital cushions than horses confined to soft stall footing. Atrophied digital cushions are a significant risk factor for navicular syndrome.

The pulse felt in the digital arteries running along the sides of the fetlock joint and pastern. Normally subtle and hard to detect. A bounding or pounding digital pulse — noticeably stronger than usual — indicates increased blood pressure in the foot and accompanies laminitis, abscesses, and other inflammatory conditions. Learning to identify a normal vs. abnormal digital pulse is a critical horse owner skill.

A lightweight hammer (typically 12–16 oz) specifically designed for driving horseshoe nails. The slightly offset head and particular weight distribution allow precise, controlled nail driving at the correct angle to emerge through the hoof wall at the white line. Different from the heavier turning hammer used for shaping shoes on the anvil.

A shoe shaped like an egg — the branches extend behind the heels and are connected by a curved bar. Provides heel and palmar foot support, distributes weight behind the hoof, and reduces tension on the navicular structures and DDFT. Commonly used for navicular syndrome, low-heel conformation, and palmar foot pain. Named for its oval shape.

A hormonal disorder characterized by insulin dysregulation, regional adiposity (fat deposits at the crest, tailhead, and behind the shoulder), and a predisposition to laminitis. Affects easy-keeper breeds disproportionately. Managed through strict diet control — limiting non-structural carbohydrates — and regular exercise. Every horse with unexplained recurring laminitis should be tested for EMS alongside PPID.

The complete loss or sloughing of the hoof capsule — the outer wall, sole, and frog separating from the underlying sensitive structures. The most severe possible consequence of catastrophic laminitis, where the laminar connection fails entirely. Requires intensive veterinary management and, if survived, many months of regrowth. Fortunately rare, but documented in severe founder cases.

A modification where the shoe is made wider or longer on one side — medially (inside), laterally (outside), or at the toe — to change how the hoof lands and loads. Lateral extensions help correct varus deformities in foals; medial extensions address valgus. Toe extensions ease breakover. A precision corrective tool requiring accurate diagnosis before application.

A skilled tradesperson who trims and shoes horses' hooves. Distinct from a blacksmith (who works metal generally) in that a farrier specifically works on horses and requires knowledge of equine anatomy, biomechanics, and pathology alongside metalworking skills. The word derives from the Latin ferrarius (iron). A good farrier is as important to a horse's health as a good veterinarian.

An outward distortion of the hoof wall where it spreads away from the coffin bone rather than following its contour. Causes include long-toe syndrome, poor balance, excessive moisture, and some nutritional deficiencies. Flares create leverage that stresses the laminae and must be addressed through rasping and corrective trimming. The hoof wall should follow a straight line from coronary band to ground when viewed from the side.

Two tendons run down the back of the lower limb: the Deep Digital Flexor Tendon (DDFT), which attaches to the coffin bone, and the Superficial Digital Flexor Tendon (SDFT), which attaches to the short pastern bone. Both pass through the digital sheath behind the fetlock. Excessive tension (from poor hoof balance) or trauma can damage either tendon — DDFT injury is often associated with navicular syndrome.

A furnace used to heat metal to working temperature for shaping. Modern farriers typically use compact propane forges that can heat a shoe to bright orange in 2–3 minutes. Traditional coal forges are still used but less common in field work. The forge enables hot shoeing — heating and custom-shaping shoes to precisely fit the individual hoof.

A gait fault where the hind toe strikes the bottom of the front shoe during movement, producing a characteristic clicking sound at the trot. Common in young, unfit, or poorly collected horses. Can be addressed by speeding up front breakover (rolled or squared toe on front shoes), slowing hind breakover, or improving the horse's way of going through training.

The common term for laminitis, particularly chronic laminitis with coffin bone rotation or sinking. Technically, founder refers to the structural changes that result from laminitis — when the coffin bone has moved. "He foundered" implies there has been rotation or sinking; "he has laminitis" may describe the acute inflammatory episode before structural change. In common use the terms are interchangeable.

The V-shaped, rubbery structure in the center of the solar surface of the hoof. Functions as a shock absorber, traction device, and — critically — a blood pump. When the frog contacts the ground and compresses the digital cushion, it pushes venous blood back up the leg (the "frog mechanism"). Must contact the ground to function. Thrush and canker affect the frog primarily.

A shoe with a groove (the fuller or crease) pressed into the ground-facing surface around the perimeter. The fuller improves nail placement, provides traction, and reduces shoe weight versus a plain stamped shoe. The standard shoe for most everyday shod horses. The nail holes are punched through the fuller, ensuring proper nail placement angles.

A shoe applied with adhesive (typically polyurethane epoxy) rather than nails. Used when the hoof wall is too thin, damaged, or brittle to hold nails securely, or when nailing would cause further damage. Commonly used in laminitis cases where the wall has separated, in horses with white line disease, or in foals needing corrective extensions. Requires a dry hoof surface and proper preparation for adhesion.

Horizontal bands visible on the hoof wall reflecting changes in growth rate — nutritional changes, illness, or seasonal variation can all produce rings. Diverging rings — where the rings at the toe are closer together than at the heel — indicate previous laminitis episodes, as inflammation slows toe growth disproportionately. Reading a hoof's growth rings is like reading tree rings: each tells a story.

The bottom of the hoof — the surface facing the ground, consisting of the hoof wall's bearing edge, the sole, bars, and frog. Proper ground surface orientation (balanced medial-laterally and anterior-posteriorly) is the fundamental goal of trimming and shoeing.

A cutting tool that fits in the square hardy hole in the anvil face. The hot shoe is placed over the hardy's cutting edge and struck with a hammer to sever the metal cleanly. Used for trimming shoe branches to length and making cuts that require precision. Working with a hardy requires the shoe to be at proper working temperature — too cold and the metal won't cut cleanly.

A bar shoe with a V-shaped or heart-shaped bar that extends inward to contact and support the frog. By loading the frog, it transfers weight away from the hoof wall and laminae — critical in laminitis where the laminar connection is failing. Must be fitted precisely; a heart bar that presses too hard on the frog can cause more damage. Fitting requires radiographs and close vet-farrier collaboration.

The rounded, soft structures at the very back of the hoof, flanking the central groove of the frog. Composed of fibrocartilage covered by skin — they are the most pliable part of the hoof exterior. Heel bulbs can be injured by overreach wounds (when the hind hoof strikes the front), wire cuts, or repeated trauma, and injuries here can affect gait permanently.

The angle of the front wall of the hoof relative to the ground, measured in degrees. Optimal hoof angle aligns the hoof-pastern axis — the front of the hoof wall should be parallel to the pastern. For most horses this falls between 50–55° on the front feet and 55–60° on the hinds. Broken-back (too low) or broken-forward (too high) hoof-pastern angles indicate imbalance and create excessive tendon and ligament stress.

The primary hand tool for trimming the sole, frog, and bars. Available in left- and right-handed versions with curved blades. Must be kept razor-sharp — a dull hoof knife requires force that causes slipping and injury. Different blade profiles (loop knife, straight blade, searcher) are used for different tasks. Every farrier maintains multiple knives at different stages of sharpness.

Heavy-duty cutting pliers used to remove excess hoof wall length before rasping. Available in various jaw lengths; the right jaw length for the horse's hoof size matters for control and precision. Dull nippers crush and shatter horn rather than cutting cleanly, stressing the hoof wall. Must be sharpened regularly.

The alignment of the front of the hoof wall with the pastern bones when viewed from the side. A straight HPA means the hoof wall angle matches the pastern angle — optimal. A broken-back HPA (toe too long, heel too low) puts excessive stress on the DDFT and navicular structures. A broken-forward HPA (heel too high) stresses the extensor tendon and coffin joint. Correcting HPA is a primary objective of remedial trimming.

A simple, pointed tool used to remove packed debris from the hoof — dirt, manure, gravel, and bedding from the sole, frog, and sulci. The most important hoof care tool a horse owner uses. Should be used daily, working heel to toe. Picks with a stiff brush on the back allow cleaning after picking. Keep multiples at every location where horses are handled.

The practice of heating a shoe in the forge, shaping it precisely on the anvil, and briefly burning it onto the prepared hoof to check and refine the fit before nailing. Hot shoeing allows for exact custom fitting impossible with cold shoes, seals the white line slightly with the burn, and allows the farrier to address any hoof irregularities. Produces superior results, particularly for horses with therapeutic needs or unusual hoof shapes.

The distal sesamoidean impar ligament — connects the navicular bone to the coffin bone. Part of the navicular apparatus. Damage or degeneration of this ligament contributes to navicular syndrome and palmar foot pain. Visible on MRI and sometimes on contrast radiographs.

A gait fault where one leg strikes the inside of the opposite leg during movement. Most common in horses that are base-narrow or toed-out. Can cause wounds on the inside of the fetlock or cannon bone, sometimes requiring protective boots. Addressed through shoeing modifications (lateral extensions, adjusted shoe placement) and sometimes conformation-appropriate trimming.

A metabolic condition where body cells become less responsive to insulin, causing elevated blood insulin levels after carbohydrate intake. High insulin directly damages lamellar tissue in the hoof — the primary mechanism behind pasture-associated and dietary laminitis. The cornerstone of laminitis prevention in IR horses is strict carbohydrate (NSC) restriction.

The structural protein that forms hoof horn, hair, and nails. Hoof wall is approximately 90% keratin by dry weight, organized into tubular and intertubular horn. The quality and hardness of keratin is influenced by genetics, nutrition (particularly zinc, copper, and biotin), and environmental moisture. Keratin synthesis requires adequate dietary protein and specific trace minerals.

A benign tumor of keratinized cells (horn cells) that grows within the hoof capsule, typically at the white line or sole. As it grows, it presses on the coffin bone, eventually causing a visible indentation on the bone's surface (seen on radiograph) and lameness. Treatment is surgical removal, which requires cutting an opening in the hoof wall. Prognosis is generally good with complete removal.

Interlocking leaf-like structures that bond the coffin bone to the inner hoof wall. Sensitive laminae (primary and secondary) arise from the coffin bone's surface and contain blood vessels and nerves. Insensitive laminae arise from the inner hoof wall and interdigitate with the sensitive laminae like interlocked fingers. This bond supports the horse's full weight. Laminitis is inflammation and failure of this bond.

Inflammation of the sensitive laminae caused by disruption of blood flow to the hoof. The lamellar bond weakens and can fail, allowing the coffin bone to rotate or sink within the hoof capsule. A veterinary emergency. Causes include dietary overload (grain, lush pasture), systemic illness, Cushing's disease (PPID), insulin resistance (EMS), and mechanical overloading of one limb while the other is injured.

Paired flexible cartilage extensions of the coffin bone that project upward on each side of the heel above the coronary band. Palpable as firm but slightly springy structures above the hoof at the heel. They enclose the digital cushion and contribute to the hoof's expansion mechanism. When they ossify (calcify), the condition is called sidebone.

The equality of the inside (medial) and outside (lateral) hoof wall heights when the hoof is viewed from the front. A horse standing on level ground should have a level hoof from side to side, with the joint axis parallel to the ground. Imbalance creates unequal joint loading, contributing to arthritis and asymmetric wear patterns.

One of the most common and damaging hoof imbalances — the toe grows long while the heel collapses, creating a broken-back hoof-pastern axis. Puts excessive, continuous tension on the DDFT and navicular structures. Contributes to navicular syndrome, DDFT tears, coffin joint arthritis, and heel pain. Correction requires regular farrier attention to keep the toe short and rebuild heel height, often combined with wedge pads during the transition period.

Horizontal ridges on the hoof wall that indicate previous episodes of laminitis. Distinguished from normal growth rings by their pattern: in laminitis rings, the spacing between rings at the toe is narrower than at the heel — because laminitis slows horn production at the toe disproportionately. Multiple diverging rings indicate multiple episodes. A horse with laminitis rings has a history — ask about it.

The mechanical force exerted on the laminae when excess hoof wall extends beyond the coffin bone's support. Long toes and flares create leverage that stresses the lamellar bond, particularly during movement. Reducing leverage through trimming is one of the most important preventive measures in hoof care — especially in horses prone to white line disease or laminitis.

A sulfur-containing essential amino acid required for keratin formation. Found in adequate amounts in most balanced diets, but horses with poor protein intake or low-quality hay may benefit from supplementation. Sulfur from methionine contributes to the disulfide bonds that give keratin its strength. Often included in commercial hoof supplements alongside biotin.

The inside wall of the hoof (toward the midline of the horse). Typically slightly steeper and taller than the lateral (outside) wall in a normally conformed horse. The medial-lateral balance is assessed during every trim and is critical to joint loading symmetry.

Hooves are approximately 25% water by weight. Adequate internal hydration (from the horse drinking sufficient water) and appropriate external moisture maintain the pliability and function of hoof horn. Excessive dryness leads to brittleness and cracking; excessive wetness (especially wet-dry cycling) weakens the wall and promotes infection. External conditioners are secondary to the horse's hydration status.

A skin condition affecting the pasterns and lower leg — dermatitis caused by prolonged wet and muddy conditions that break down the skin barrier. More a skin condition than a hoof condition, but relevant to farriery because feathered draft breeds and horses with white legs are most susceptible, and the condition can spread to affect the coronary band. Treatment involves cleaning, drying, and topical antimicrobials; preventing re-exposure to mud is essential.

A trimming technique that bevels the outer edge of the hoof wall from the white line outward and upward at approximately 45 degrees, then rounds the resulting edge smooth. Mimics the natural wear pattern found on wild horses moving on abrasive rock and hard terrain — where constant movement files the wall edge into a rounded bevel automatically. Named for the Great Basin mustangs whose hooves display this profile most prominently. Applied to the hoof wall itself with a rasp, on barefoot and shod horses alike.

Mechanical effect: Moves the breakover point palmarly (toward the heel), reducing the duration and peak force of deep digital flexor tendon (DDFT) loading at the end of each stride. Eliminates the sharp wall edge that acts as a stress concentrator, reducing chip and crack formation. Reduces leverage on the laminae from any remaining toe length. Allows breakover to be shifted back without reducing vertical toe height beneath the coffin bone — which would risk soreness.

Scientific basis: Wild horse hoof research by Jaime Jackson (measuring 1,000+ hooves at BLM corrals over four years) identified the mustang roll as a consistent feature of sound wild horse hooves. Controlled kinematic studies, including Van Heel et al. (2010) in the Equine Veterinary Journal, confirmed that rolled toe configurations produce smoother hoof-unrollment and lower peak loading during breakover on sound horses. Lameness rates in wild horse populations are estimated below 2% compared to 15–20% in domestic horses — the mustang roll is one of several structural differences contributing to this gap.

Application: Performed by rasping from the white line outward and upward around the entire perimeter of the hoof wall, or focused at the toe where breakover leverage is greatest. The degree of roll is calibrated to the horse's terrain — horses on hard abrasive ground can support a more aggressive roll; horses on soft wet grass need a more conservative one to maintain traction. Once considered exclusively a barefoot trimming concept, it is now increasingly applied as a standard finishing step by conventional farriers on shod horses.

A specially designed nail for attaching shoes to hooves. The head sits in the shoe's crease; the shank tapers and has a slight bevel that causes it to angle outward as it rises through the hoof wall, emerging at the correct height (typically 3/4 to 1 inch above the shoe) to be clinched. Sizes are numbered (3, 4, 5, etc.) based on shank diameter. Nail placement in the white line — not into sensitive tissue — is critical.

A small, boat-shaped bone located at the back of the coffin joint that acts as a pulley for the DDFT. The tendon passes under and around the navicular bone, cushioned by the navicular bursa. Degeneration of the navicular bone, its cartilage, the bursa, or associated ligaments causes palmar foot pain (navicular syndrome) — one of the most common causes of chronic front-end lameness.

A fluid-filled sac between the DDFT and the navicular bone that reduces friction as the tendon slides over the bone. Inflammation of the bursa (bursitis) is a component of navicular syndrome. Can be injected directly (under ultrasound guidance) with corticosteroids for diagnostic and therapeutic purposes.

A chronic pain syndrome originating in the heel area — involving the navicular bone, navicular bursa, DDFT, impar ligament, or suspensory ligaments of the navicular bone. One of the leading causes of front-end lameness. Diagnosis requires nerve blocks and imaging. Management (not cure) includes corrective shoeing (egg bar, raised heels, pads), controlled exercise, and medications. MRI has refined diagnosis significantly by identifying soft tissue involvement invisible on radiograph.

Surgical removal of a section of the palmar digital nerves to desensitize the heel area — used as a last resort in navicular syndrome when other management has failed. Eliminates heel pain but also removes sensation, which means foot injuries may go undetected. Horses must be carefully monitored after neurectomy. A significant, permanent procedure — not undertaken lightly.

The conversion of soft tissue (cartilage, ligament) into bone. In the horse's foot, relevant to sidebone (ossification of lateral cartilages) and ringbone (periosteal bone proliferation around joints). Ossification is generally a response to chronic stress, concussion, or inflammation. Once complete, the new bone is permanent.

When the hind hoof strikes the heel or heel bulb of the front hoof during movement. Can cause serious wounds and pull front shoes. Common in horses working collected or jumping when tired. Addressed with bell boots on the front feet, adjusting shoe length on the hinds, or squaring toes to alter the hind breakover. A frequent cause of lost front shoes in performance horses.

Material placed between the shoe and the hoof for protection or therapeutic purposes. Full pads cover the entire sole. Rim pads cover just the bearing surface. Materials include leather, rubber, plastic, and EVA foam. Pads protect thin soles from bruising, maintain moisture under the sole, and can be used to apply medicaments. The space under full pads is often packed with silicone or oakum to prevent debris packing.

The two bones between the fetlock and the hoof: the long pastern bone (P1) between the fetlock joint and pastern joint, and the short pastern bone (P2) between the pastern joint and the coffin joint. The pastern joint (between P1 and P2) is the site of high ringbone. The coffin joint (between P2 and P3) is the site of low ringbone. Hoof angle directly affects the stress on these joints.

A thin, waxy coating produced by the perioplic corium at the top of the hoof wall that covers the outer surface of the wall and helps regulate moisture loss. Gives the hoof its natural gloss when healthy. Aggressive rasping of the outer hoof wall removes the periople and its protective function — a reason why rasping only the bearing surface (not the outer wall) is preferred unless flares must be addressed.

A surgical procedure used in foals with angular limb deformities to accelerate bone growth on the lagging side of the growth plate. The periosteum (bone membrane) is scraped on the concave side of the deviation, stimulating faster growth that corrects the alignment. Done early — typically before 3 months — while growth plates are responsive.

A two-part polyurethane foam mixed and poured into the space between the shoe and sole while liquid. Sets quickly to a firm, slightly flexible material that provides custom-fitted support across the entire solar surface. Superior to flat pads for sole protection because it conforms exactly to the individual hoof. Used for thin soles, laminitis management, sole injuries, and horses competing on hard surfaces.

Specialized pliers with curved jaws designed to safely pry and remove shoes after clinches are cut. The jaws work under the shoe from heel to toe, leveraging against the shoe rather than the hoof wall. Available in various jaw sizes for different shoe weights. Always used after a clinch cutter — never pull a shoe with clinches intact.

A large, double-sided file used to level the bearing surface of the hoof wall, smooth nail clinches, and remove flares. One side is coarser (for rapid material removal), the other finer (for finishing). The most used tool in a farrier's kit — and the one that wears out fastest. A dull rasp takes far longer and produces a less precise result. Many farriers use a new rasp every few horses.

Re-nailing the same shoe after trimming the hoof — as opposed to applying new shoes. Common when the shoe has worn evenly and still has adequate material. A good shoe can typically be reset once before replacement. The farrier removes the shoe, trims the hoof, and re-fits and nails the same shoe back on. Cost is less than a full new set.

A pad that sits only on the bearing surface of the shoe (the rim) without covering the sole. Provides some cushioning and a slight heel elevation while allowing sole contact with the ground. Less protective than a full pad but easier to manage — debris doesn't pack under the pad as it can with full pads.

New bone growth (periosteal proliferation/osteoarthritis) around the pastern joint (high ringbone) or coffin joint (low ringbone). Articular ringbone involves the joint surface; periarticular ringbone surrounds the joint without directly involving the cartilage. Causes include concussion, poor conformation, repetitive stress, and injury. Management includes shoeing modifications to reduce concussion and range of motion. Some cases ankylose into functional soundness.

A shoe with a curved or rocked toe that shifts the breakover point palmarly (toward the back) and allows the hoof to roll forward more easily. Reduces stress on the DDFT, navicular structures, and coffin joint. Used in navicular syndrome, laminitis, LTLH, and any condition where reducing toe leverage and easing breakover is beneficial.

Movement of the coffin bone within the hoof capsule where the toe of the bone tips downward, driven by the pull of the DDFT as the lamellar bond fails. Measured in degrees on radiograph. Mild rotation (under 5°) may be managed successfully; severe rotation (15°+) carries a poorer prognosis. When the rotated tip of the coffin bone penetrates the sole, the condition is called "sinker" and is a grave emergency.

White line disease specifically affecting the toe area — a fungal and bacterial infection producing crumbly, seed-like infected horn at the toe. Named for the texture of the tissue when debrided. Long toes are a primary risk factor. Treatment: debridement and antifungal treatment, correction of the underlying long toe.

The vascular, nerve-containing laminar tissue arising from the coffin bone's surface. Interdigitates with the insensitive laminae of the inner hoof wall to form the lamellar bond. Contains the blood supply that nourishes the hoof. When this tissue becomes inflamed (laminitis), the bond weakens. Nails driven into sensitive laminae cause immediate, severe pain — the nail placement skill of a farrier is measured by consistent avoidance of this tissue.

A condition where the medial and lateral heel bulbs are at significantly different heights, causing the heels to shear past each other during loading rather than compressing together. Creates intense stress at the quarter of the hoof and is associated with quarter cracks, coronary band trauma, and heel pain. Often related to medial-lateral hoof imbalance and requires corrective trimming and sometimes bar shoe support.

The ossification (calcification) of the lateral cartilages into bone. Palpated as firm, non-springy structures at the heel above the coronary band where the cartilages should normally feel slightly flexible. Common in heavier breeds and working horses on hard ground. Often found incidentally on radiograph with no lameness. When painful, management focuses on reducing concussion through appropriate shoeing and footing.

The vertical downward displacement of the coffin bone within the hoof capsule when the lamellar bond fails uniformly around the entire circumference — as opposed to rotation, which is tipping. Sinking is generally a more serious prognosis than rotation. The coronary band appears to sink or become level with the hoof wall. A grave emergency requiring immediate intensive treatment.

A bucket of water at the forge used to cool hot shoes after shaping and checking fit. Plunging a shoe into the slack tub hardens it slightly through rapid quenching and prevents further unintended shape changes. Also used to test if a shoe is cool enough to handle — if it sizzles, it's still hot.

A rubber pad designed to prevent snow from packing inside the shoe during winter work. The bubble style has a raised dome that flexes with each step, popping accumulated snow out. Without snowball pads, shod horses can accumulate dangerous ice balls inside their shoes, effectively walking on stilts with serious fall risk. A simple, inexpensive addition for any horse worked in snow.

The slightly concave plate of horn that covers the bottom of the hoof inside the hoof wall border. Should bear minimal weight — the hoof wall carries the load. Protects the sensitive solar corium and the coffin bone beneath it. Thin soles (less than 15mm) allow bruising from ground contact and are a significant performance limitation. Sole thickness is measurable on radiograph and ultrasound.

Application of thumb pressure to various areas of the sole to identify pain points — suggesting abscess location, thin sole bruising, or foreign body. A simple first-level diagnostic before using hoof testers. Pain response (flinching, pulling away) on sole pressure at the toe in a laminitic horse indicates the coffin bone tip may be close to the solar surface.

Removable threaded plugs screwed into pre-tapped holes in the shoe to provide traction on specific footing conditions. Sizes range from small road studs (for wet grass) to large mud studs (for heavy going). Studs are removed when the horse is not working and holes plugged with cotton wool to prevent damage. Commonly used in jumping, eventing, and dressage. Studs must be balanced — equal size on medial and lateral to avoid uneven footing.

The grooves of the frog. The central sulcus runs down the middle of the frog; the lateral sulci run on either side between the frog and the bars. These grooves can be shallow and wide (healthy) or deep and narrow (contracted). Thrush preferentially colonizes deep sulci where anaerobic conditions are ideal. Daily picking to clear debris from the sulci is the primary prevention for thrush.

Laminitis that develops in a sound limb that has been bearing excessive weight because the opposite limb is injured or non-weight-bearing. A devastating complication of serious limb injuries. The increased and continuous loading reduces blood flow to the support limb's hoof laminae. Prevented by aggressive management — keeping the horse moving minimally, using deep bedding, and sometimes applying frog support pads to distribute load. Killed Barbaro following his 2006 Preakness injury.

A bacterial infection (primarily Fusobacterium necrophorum) of the frog and sulci, caused by anaerobic bacteria that thrive in packed, wet, oxygen-free environments. Produces a characteristic foul, rotten odor and black tarry discharge. Mild thrush causes no lameness; severe thrush invading sensitive tissue is painful and requires professional debridement. Treatment: clean daily, open sulci for air exposure, apply topical thrush remedies, and critically — improve footing conditions.

Long-handled pliers used to hold hot shoes on the anvil during shaping and carry them to the horse for fitting. Different jaw styles hold different shoe widths and types. Essential forge equipment — never handle a freshly forged shoe without tongs. A good farrier moves efficiently between tongs and hammer without losing shoe temperature.

The front-facing portion of the hoof — the wall from approximately 10 o'clock to 2 o'clock positions when viewed from below. The last part of the hoof to leave the ground in each stride (the breakover point). Long toes create leverage stress on the laminae and increase DDFT tension. "Keeping the toe back" is one of the most repeated phrases in corrective farriery.

A vertical crack in the toe of the hoof wall, typically starting at the ground surface and growing upward (grass crack). Often caused by a long toe creating excessive leverage, or dry-wet moisture cycling. Superficial toe cracks are cosmetic; cracks that extend to the coronary band, penetrate to sensitive tissue, or cause lameness require farrier treatment — including stabilization with wire, fiberglass patches, or clips.

Microscopic cylindrical structures running vertically through the hoof wall from coronary band to ground surface, embedded in intertubular horn. Tubules give hoof horn its directional strength — resistant to splitting along the tubule direction, weaker across it. The arrangement of tubular horn is why hoof cracks tend to run vertically (along tubule direction) rather than horizontally.

A heavier hammer (typically 2–3 lbs) used for shaping hot shoes on the anvil. The flat face is used for general shaping; the cross-peen (narrow, rounded edge) for drawing metal out or making detailed modifications. Different from the lighter driving hammer used for nailing. A skilled farrier alternates between the two as naturally as a carpenter switches between hammers.

The formation of blood clots within the digital vessels, implicated in the vascular disruption that causes laminitis. One proposed mechanism of laminitis involves arteriovenous shunting — blood bypassing the lamellar capillaries through direct arteriovenous connections — combined with thrombosis in the lamellar vessels, cutting off blood supply to the sensitive laminae.

A heel where the hoof wall angle at the heel is significantly lower than the angle at the toe — the heel has "run forward" under the horse. The hoof's heel tubules angle forward rather than being nearly vertical. Severely underrun heels indicate long-standing long-toe/low-heel syndrome and significantly compromise the hoof's shock-absorbing capacity. Among the more difficult hoof conditions to correct.

A horse managed without metal shoes, relying on regular trimming to maintain hoof balance and wear. Does not mean "no hoof care" — barefoot horses still require regular farrier visits for trimming, typically every 6–8 weeks. Many horses thrive barefoot with appropriate diet, footing, and management. The barefoot movement has produced refined trimming methodologies (the "natural trim") based on wild horse hoof morphology.

Valgus: an outward deviation of the limb below the affected joint (knock-kneed). Varus: an inward deviation (bow-legged). Both are types of angular limb deformity. The description always refers to the deviation of the limb distal to (below) the affected joint. Carpus valgus (knock-kneed at the knee) is the most common ALD in foals and frequently self-corrects. Fetlock varus is more serious and less likely to self-correct.

A radiographic technique where contrast dye is injected into the digital vessels and X-rays taken to visualize blood flow patterns within the hoof. Used in laminitis cases to assess the degree of vascular compromise and guide treatment decisions. Areas of poor or absent contrast uptake indicate tissue ischemia. Increasingly used as a diagnostic tool in serious laminitis management.

The hard outer shell of the hoof — the visible, pigmented structure that bears the horse's weight and is nailed to when shoeing. Made of keratin organized in tubular and intertubular horn. Grows continuously from the coronary band downward at approximately 3/8 inch per month (full growth-out takes 9–12 months). The wall is divided into toe, quarters (sides), and heels.

A tapered pad placed under the shoe (thick at the heel, thin at the toe) to elevate the heel angle. Used to reduce DDFT tension in navicular syndrome and LTLH cases, or during the transition period while heel height is being rebuilt through trimming. Must be used carefully — excessive heel elevation long-term can cause other issues. Ideally a temporary measure while conformation improves.

The junction between the hoof wall and the sole, visible on the ground surface as a light-colored band running inside the hoof wall border. Marks the location of the insensitive laminae. The critical landmark for nail placement — horseshoe nails are driven just outside the white line into the insensitive hoof wall, never inside it (which would hit sensitive laminae). Separation or crumbling of the white line signals white line disease.

A fungal and bacterial infection of the non-pigmented inner hoof wall (the white line zone) that causes separation and degradation of horn. Appears as crumbly, chalky, or powdery material when the sole is probed at the wall junction. Does not smell strongly (unlike thrush). Ranges from superficial/cosmetic to extensive separation threatening coffin bone stability. Treatment requires debridement of all infected tissue and antifungal treatment, followed by months of regrowth.

Winging: the hoof arcs outward during flight before landing — typically seen in toed-in horses. Paddling: the hoof arcs outward in a more exaggerated sweep. Both are related to the hoof's breakover point relative to the limb's axis. Trimming the breakover point in line with the limb can reduce but rarely eliminate these movement patterns in horses with conformational causes. Primarily cosmetic concerns unless the horse is interfering.