Chapter 45: Foot DRASTAs Flashcards
Abscess
D: A cavity filled with pus and necrotic tissue. The farrier’s concern is an abscess or infection inside the hoof capsule.
R: An abscess occurs because bacteria have penetrated the horny regions of the hoof.
A: Can involve any portion of the hoof. Most commonly involved structures include horny and sensitive sole, horny laminae, sensitive laminae, and coronary band.
S: Grade 4 lameness, heat, bounding pulse.
T: Cause to drain, poultice, and protect with pad or boot.
A: Full recovery expected.
Canker
D: An abnormal and accelerated growth of tissue from the sensitive frog. It can also involve the sole, hoof wall, bulbs, and coronary band in severe cases. Most begin at the frog and move to the rest of the foot.
R: True cause unknown. Draft horses seem to be more susceptible.
A: Sensitive frog, sometimes also sole, bulbs, wall, and coronary band.
S: Uunusual appearance, ammonia odor, and will easily bleed. May resemble a cabbage.
T: Removal of all growth, 10% benzoyl peroxide mixed with acetone applied to the foot with ground up metronidazole pills. Bandage and cover with hospital plate.
A: Generally believed to be incurable, but above treatment has been successful.
Club Foot
D: A club foot is one that is abnormally steeper than it should be based on the rest of the horse’s conformation. This problem is graded by degree going from Grade 1 (least severe) to Grade 4 (knuckled over).
R: diet, conformation, high-low syndrome, injury, founder.
A: The deep flexor muscle and tendon, coffin bone, cannon bone, and possibly the superficial flexor tendon and suspensory ligament.
S: One foot at a steeper angle than the other foot.
Grade 1: about 5 degrees steeper
Grade 2: 5-10 degree steeper
Grade 3: dish in the toe, coronary band almost parallel to the ground
Grade 4: Coronary band higher at the heels, dish in the toe, and fetlock knuckling over
T: change diet, trim and shoe for proper HPA, tenotomy and toe extensions in severe cases.
A: Grade 1-2 horses may still be usable but may be prone to stumbling. Grade 3-4 may not be usable but can be managed for comfortable living.
Coffin bone fractures
D: The distal phalanx has been chipped or suffered a break.
R: P3 fractures are generally caused by trauma from repeated concussion or may occur in coffin bones that have Ben weakened by pedal osteitis, bone cysts, or other causes. Bearing a lot of weight then twisting hard can also lead to a fracture.
A: coffin bone. Can be articulate or non articulate, depending on if the break involves the coffin joint.
Several types: sagittal, margin or rim, wing, and extensor process fractures.
S: Mild to severe lameness. Fractures involving the joint (articulate) will cause the horse to be grade 4 lame.
T: stall rest, wide-webbed bar shoe with side clips and pour-in pad, or use a regular pad if infection is present.
A: 8-10 months of recovery, but full recovery is possible.
Corns
D: Corns is the common name given to damage in the area of the foot known as the seat of corn.
R: Pressure in the seat of corn area. Can be from debris, leaving shoes on too long,tight shoeing or shoeing with heel caulks, etc.
A: seat of corn, almost always on the front feet.
S: dry/red corn (bruise), moist corn (seeping liquid), and infected corn (aka suppurating, horse will be sore and have an abscess).
T: full fit wide-webbed shoe, g-bar, z-bar, heart bar, or straight bar, possibly equi-pak.
A:
Hoof Cracks
D: A split or fissure in the hoof wall that is more or less vertical
R: drastic moisture changes, uneven weight bearing, coronary band injury, weak hooves, improper nutrition, white line disease, keratosis, flared and dished horn, or just overall poor horn.
A: Hoof wall. Severe enough cases can involve any portion under the hoof wall such as coffin bone, lateral cartilages, and laminae.
S: deep crack, potential lameness
T: stabilize the hoof (proper trimming/shoeing, stabilize with acrylic, etc) and allow time to grow.
A: Most cracks will improve with stabilization and time for the foot to grow out again.
Dropped Sole
D: Sole that is prolapsed below the border of the hoof wall. The sole appears convex instead of concave.
R: conformation (wide, flat feet that have a lot of angle to the side wall at the quarter), hoof wall becomes overly worn or broken off, thick shoes and hard work, foundered feet and sinkers.
A: sole, hoof wall, and the laminae in the case of founder or sinker.
S: bruising, lameness from bruised sole, lameness from sinker, sole protrudes distally.
T: protect with deep-seated shoe, cupped shoe, equi-pak, pads, or hospital plate.
A: Shoes should help the hoof wall to grow past the sole. Tight shoeing schedule to prevent flaring should help fix this problem.
Founder and Laminitis
D: Founder is the separation of the coffin bone from the hoof wall.
R: Failure of the bond between the laminae. Risks include genetics, over-feeding carbohydrates, incomplete delivery of the placenta, excessive watering of hot stock, mechanical founder.
A: Pre-laminitic: digital arteries, veins, AVAs, and basement membrane
Laminitis: dermal and epidermal laminae
Founder: deep flexor tendon, sole, P3 (coffin bone), dorsal coronary band, laminae
S: acute phase: severely lame, characteristic laminitis stance
Subacute: majority of rotation occurring, often there will be infections in the foot, bounding pulse, extremely lame horse, hair standing out at coronary band, heat and swelling, body condition deteriorating.
Chronic: pain and rotation had subsided. Horse stilll lame and sore,foot appearance changes, feet easily quicker, sole can abscess and prolapse, lots of bruising.
T: any suspicion of founder/laminitis means vet should be called out immediately. Use impression material or polymer urethane in the rear half of the foot for the acute and subacute phase, followed by a W-shoe or similar shoeing strategy to place weight on the frog in the chronic phase.
A: outcome is guarded at best. Possible to recover fully, but can also become fatal very quickly.
Hoof Avulsion
D: The hoof capsule has come off of the coffin bone.
R: infection, severe founder or white line disease, nerved horses who get their feet caught, or getting the foot caught while moving quickly.
A: hoof capsule and coriums
S: Missing hoof capsule, severe lameness
T: bandage and doctor continuously until some foot grows out. At that point, a W-shoe may be partially nailed and glued to a foot.
A: Little chance of soundness if horse survives.
Keratoma
D: Tumor of the horn that generally involves the stratum internum
R: can occur from continuous irritation to the hoof from injury or just be excess keratinization
A: hoof wall and laminae. In severe cases, the coffin bone can be remodeled or foot can become infected and separated from the coffin bone.
S: may or may not have any lameness, radiographs necessary.
T: surgical removal with varied shoeing afterwards.
A: each case must be evaluated individually.
Navicular
D: Lameness caused by pain in the navicular region.
R: definite cause has yet to be identified, but most likely caused by use of the horse, conformation, terrain lived and worked on, balance problems, heredity, age, broken navicular bone.
Concussion related: often found on steep and upright horses. Repeated stress can cause material fatigue and eventual failure.
Suspensory related: found in horses that are shallow, the deep flexor tendon is extremely tight as it passes over the navicular bursa. The pressure and wear over the navicular bone causes the navicular bursa to become inflamed.
A: navicular bone, navicular ligaments, coffin joint, deep flexor tendon, navicular bursa.
S: short, choppy stride after being immobile for a while, sensitivity to hoof testers, radio graphic evidence of bone change, “pointing” (placing one foot in front of the other when tied and placing more weight on the toe of that foot), lame on one leg but becomes lame on the other when the worst foot is blocked, horse will walk off lame with. A wedge placed under the toe, horse does not want to stand on handle of hoof knife placed under the frog, flexi on tests on the coffin joint illicit a lameness response.
T: straight bar, quarter clips, rocker toe, equi-pak, increase angle on horses that are not overly steep. Onion heel shoe may also be used.
A: will degenerate with time. Horse can often be used, but the problem will always get worse.
Pedal Osteitis
D: Inflammation of the coffin bone
R: Lack of blood supply to the coffin bone, concussion, sole pressure, chronic bruising.
A: coffin bone, blood supply to distal border of coffin bone
S: shuffling gait similar to navicular because often appears on both front feet rather than just one. Soreness present, radiographs needed for competent diagnosis.
T: protect bottom of foot and ensure no sole pressure: wide-webbed deep seated bar shoe, quarter clips, rocker toe, equi-pak. Vet is necessary
A: may become sound enough for use, but coffin bone doesn’t always return to normal on radiographs. Horse usually kept in bar shoes.
Quarter Cracks
D: cracks in the hoof wall that begin at the coronary band and split downward parallel to the tubules in the quarter region of the hoof.
R: imbalanced trim, injury, proximal coronary band displacement
A: Hoof wall and coronary band in the quarter region
S: lameness, sometimes infection or bleeding at coronary band
T: stabilize crack with polyurethane or acrylic, trim and shoe to relieve stress in the quarter area (can shoe with heart bar and float quarter)
A: can sometimes reoccur, horse can generally return to use once crack has been stabilized and grown out.
Quittor
D: infected or necrotic collateral cartilage
R: anything that allows the lateral cartilages to become infected. Abscess, direct injury, etc. More common in draft horses.
A: collateral cartilages
S: drainage in the quarter region at or around coronary band usually. Horse will be lame until drainage occurs. Constant development of abscesses.
T: vet should surgically remove infected cartilage. Shoe to stabilize post-op.
A: Most horses make a full recovery once infected tissue is removed. Complications in surgery often make the problem much worse.
Sheared Heels
D: bulbs of the foot are in different planes
R: imbalance, injury, weak feet
A: bulbs, heels of the foot, and coronary band
S: most horses do not shoe lameness. May lead to soft heel cracks
T: If no lameness, no need to fix. Trim and balance normally. If needed, shoe with heart bar and float the heel on the side bulbs is higher.
A:
