The Hoof

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The Hoof
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Physiology of foot

• Structures of the foot work together to absorb
  concussion.
• Heels expanded by frog action.

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• Frog pushes upward on digital cushion which push
  lateral cartilages outward.
• Lateral cartilages compress on blood vessels
  draining the foot - sending some blood back to
  foot and trapping some in the foot.
• Third phalanx, sole, laminae,navicular bone,
  pasterns, knee and shoulder aid in absorbing
  concussion.

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Hoof care

• Need to be cleaned daily to avoid thrush.
• Inspected on a regular basis for cracks, unusual
  growth, condition.
• Need to be trimmed level.
• Corrective work needs to be done at a very young
  age or will only make horse sore.
• Shoes should be reset every 4-8 weeks, average 6
  weeks.

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Pathological conditions of hoof

• Could include Thrush, brittle feet, contracted
  heels, false quarter, bruising of sole and frog,
  corns, nail bind, puncture wounds, seedy toe,
  sandcrack, splits in wall, horn tumour,
  coronitis, pedal ostitis, laminitis, navicular
  disease, quittor, canker, forging and clicking.
• "No hoof, no horse"

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• Thrush- bacterial origin-cleanliness and daily
  cleaning.
• Brittle feet-overly dry-hoof preperations,
  protective shoes until new horn grows out.
• Contracted heels-caused by too long a toe-trim
  short.
• False quarter-inside quarter-defect in horn
  secreting tissue
• Bruising of sole and frog- large, open feet with
  low soles-poutice and shoe for protection
• Corns- a bruise where bar and hoof wall meet-
  keep weight off corn

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• Nail bind-nail driven too close to sensitive
  inner tissues-remove offending nail, poultices
  and hot bathing of foot.
• Nail pricks and punctures-abcess, if formed, must
  be drained.
• Seedy toe- deformity in hoof growth-allow horse
  to rest, take pressure off hoof wall in area.
• Sandcrack-Usually arise from dry conditions but
  also as result to papillae in coronary band- keep
  foot together and pressure off crack

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• Dry cracks-keep foot moist
• Horn tumor-keratoma- gives rise to a tumor on
  inside of hoof wall- no successful treatment
  other than nerving (median) horse.
• Coronitis-defects in growth of horn-good diet.
• Pedal ostitis - new growth at pedal bone-hard
  work at fast paces. Turn horses out for year.

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Components

• Consists of
• wall (including bars)
• sole
• frog
• Epithelia that has been keratanized

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Hoof wall

• Composed of 3 layers
• stratum externum
• formed by perioplic corial epidermis
• stratum medium
• thickest and strongest layer
• developed by coronary corial epidermis
• stratum internum
• asssociated with laminar corium

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Hoof wall growth

• Papillae projecting from coronary corium form the
  tubules, responsible for growth.
• Tubule are filled with cells that conduct water
• Intertubular horn, cementlike substance loosely
  packed cells. Holds tubules together.
  Responsible for color of foot.
• .

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• Primary and secondary sensitive laminae mesh with
  insensitive laminae.
• Foot is thickest at toe and thinnest at the
  quarter

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Sole growth and other structures

• Sole corium(sensitive sole) covers PIII- growth
  of the sole occurs here. Appproximatly 3/8"
  thick near the hoof wall
• The frog is an elastic wedge shaped structure.
• Contains central sulcus

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• About 43 moisture -compared to 24.7 for the
  wall and 37.1 for the sole
• Digital cushion-also known as plantar
  cushion-shock absorber
• Digital cushion secretes fatty secretion to keep
  moist.
• Lateral cartilage- attached to wings of 3rd
  phalanx

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Founder

• Laminar corium?Lamallae hoof wall connection
  weakened.
• Pull of deep digital flexor tends to rotate
  digital phalanx (PIII).
• Congestion of blood in certain blood vessels
• Causes

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• Overloading on grain or lush gras
• Drinking cold water
• Concussion during work on hard roads
• Exhaustion
• Untreated infections
• Acute allergic reactions

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• Increased weight on feet
• Drastic laxatives
• Heat stroke
• Immediate treatment
• Antihistimes
• Long term
• proper shoeing

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Coriums

• Perioplic corium (perioplic groove of coronary
  groove)
• Coronary corium (coronary band)
• Laminar corium (PIII bears sensitive laminae)
• Sole corium (PIII)
• Frog corium (nourishes frog)