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350 Cards in this Set
- Front
- Back
When a forelimb lameness is involved, how does the head and front end of the animal's torso move?
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They both move dorsally
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When a hindlimb lameness is involved, how does the croup and rear end of the animal move?
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They both move dorsally
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What gait/speed is the best for lameness evaluation of a horse?
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trot
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What is a trot?
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gait in which the right fore - left rear limbs and left fore - right rear limbs hit the ground at the same time
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What will you see with a subtle lameness?
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-the animal does not "settle into the lame leg"
-the fetlock does not extend/drop to the same degree as the sound limb --consider which limb the animal bears weight on most comfortably |
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What are 3 ways to test for lameness of jogging doesn't work?
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try moving on a harder surface
move in a circle (lunge line) evaluate w/rider in the saddle |
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95% of forelimb lameness occurs where?
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in the carpus of below
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Rear limb lameness most commonly involves what?
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the foot and hock
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When doing digital flexion of the forelimb, where is stress applied? (ex joint)
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navicular, coffin joint, pastern join, and fetlock
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When doing digital flexion of the forelimb, when do you start evaluating the lameness of the animal?
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evaluate the lameness after the initial 100 foot distance
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When doing digital flexion of the rearlimb, when do you start evaluating the lameness of the animal?
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immediately - if there is any incr in lameness (no 100 foot allowance as with the forelimb) it is a positive finding
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When doing flexion of the hock, how long do you hold the position and how is the horse moved afterwards?
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apply pressure on the metatarsus for approximately 2 minutes, then have the horse jogged off at a TROT (not a walk then trot)
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When doing hock flexion, when do you start evaluating the lameness of the animal?
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right away - any incr in lameness is significant
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How do you perform a stifle flexion? This is similar to what other flexion/extension test?
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pick up the limb, pull it to the rear and apply upward pressure to the metatarsus
hip extension |
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How do you start regional nerve blocks?
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always start DISTAL and move proximal
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What is the preferred anesthetic for regional and intra-articular anesthesia in the horse and why?
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Mepivicaine (carbocaine) bc it is less irritating and has a similar onset but lasts longer than lidocaine
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Where do you do a palmar digital nerve block? Where is the anesthetic injected?
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palmar aspect of the pastern joint, just proximal to the collateral cartilages
just axial to the neurovascular bundle if you can feel it (light horses) |
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What does a palmar digital nerve block anesthetize?
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the palmar 1/3 of the foot and sole (navicular complex is blocked) (heel block)
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What nerve are you blocking with a foot block?
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the dorsal brance of the palmar digital nerve
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When combined with the palmar digital nerve block, what is anesthetized when doing a foot block?
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all structures within the hoof
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When doing an abaxial sesamoid block, where is the local anesthetic injected?
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immediately caudal to the neurovascular bundle, which is at the abaxial surface of the sesamoid bone
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What does the abaxial sesamoid block anesthetize?
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all structures distal to the midpastern including the pastern joint (foot should already be blocked by the palmar digital and foot blocks)
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Where are the injections made with a low four point block?
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at the level of the distal end of metacarpals/tarsals II & IV (end of the splint bones)
palmar nerves are blocked medially and laterally just dorsal to the deep digital flexor tendon palmar metacarpal nerves are blocked medially and laterally just distal to end of metacarpal II & IV (just dorsal to the interosseous muscle) |
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What areas are anesthetized using the low four point block?
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all areas distal to the injection site (fetlock and below)
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What is scintigraphy effectively used for in evaluating lameness?
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it is effective for determining the area of involvement by not the exact problem
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What is thrush?
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a degernative condition of the frog characterized by a black necrotic odoriferous material
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What can cause thrush?
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filthy conditions
failure to clean the foot regularly lack of pressure on frog (interferes with natural cleaning) |
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Name a medication commonly used to treat thrush
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Coppertox
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Thrush: What do you do if sensitive tissue is not involved, therefore the animal is not lame?
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application of 10% formalin will clear the condition rapidly, though overuse will make the frog extremely hard
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Thrush: What do you do if sensitive tissue is involved, therefore the animal is lame?
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trim the frog to remove all abnormal tissue
apply mild disinfectants as a wet dressing and bandage daily |
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What is the prognosis for thrush?
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good
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What is "corns?" On which feet is it usually found?
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bruising of the sole at the angle of the wall and the bar (bruising of the sole in any other area is called a sole bruise)
front feet |
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Name the different classifications of "corns" and describe them
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dry - reddened area of the sole
moist - serum under the sole suppurating - secondary infection as a result of bruising |
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What usually causes corns?
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improper shoeing or leaving the shoes on for too long a time (heels of the shoes apply pressure to the sole rather than the hoof wall)
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T/F: horses that are barefoot seldom develop corns
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true
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What are the clinical signs of corns?
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lameness with a tendency to protect the heel
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How do you diagnose corns? What type or nerve block would help diagnose it?
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reaction to hoof testers when applied to the angle of the wall and bar
significant decrease in lameness following a PALMAR DIGITAL NERVE BLOCK |
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How do you fix/manage corns?
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-if the shoe is the problem, remove it
-trim the involved sole so that there is no contact w/the shoe when weight is born on the foot -drain if suppurating -rest if possible -shoeing following trimming to minimize pressure on affected area |
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NSAIDs help with corns when?
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with rest (with work, they usually prolong the problem)
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Corns: What type of shoe would be useful to protect the involved area?
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wide web shoe or a bar shoe
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What are bruised soles?
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the same sort of lesion as corns involving any area of the sole EXCEPT the angle of the wall and bar
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How do you diagnose bruised soles?
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reaction to hoof testers
discolored areas on the sole (evidence of chronic bruising) response to nerve blocks radiographs (determine if the condition has progressed to pedal osteitis) |
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What nerve blocks may be of diagnostic use to dx bruised soles?
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heel block (reduced lameness)
foot block (sound) |
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What is recommended for management of bruised soles?
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-rest and NSAIDs
-wide webshoe w/the axial side thinned by grinding or beating it down to that pressure if not applied to the sole -pads (sometimes recommended) |
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prognosis of bruised soles
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good w/proper tx and rest (sometimes up to a year if necessary)
excessive traums for long periods will result in pedal osteitis |
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What is pedal osteitis?
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an inflammatory condition involving the third phalanx that has resulted in a loss of bone density in P3
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What is pedal osteitis caused by?
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a chronic inflammatory process involving P3 - severe sole bruising (repeated concussion), laminitis, chronic subsolar abscesses
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Which foot/feet does pedal osteitis usually affect? Why?
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front feet
more weight --> more trauma |
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What clinical signs may you see with pedal osteitis?
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if excessive work it will be bilateral
short choppy gait |
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How do you diagnose pedal osteitis?
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incr rxn to hoof testers
evidence of chronic bruising (discolored areas) response to nerve blocks radiographic changes |
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What nerve blocks would be diagnostic with pedal osteitis?
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palmar digital block - improves lameness
foot block - usually sound |
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What radiographic changes might you see with pedal osteitis?
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lack of density of P3
roughening of the distal border of P3 these radiographic changes can be mimicked when normal feet are x-rayed with an incr in kV setting |
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pedal osteitis is most commonly secondary to what?
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laminitis
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How do you protect the foot with pedal osteitis?
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wide web shoe (axial border thinned to prevent contact w/the sole)
complete pads rim pads |
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How do you manage pedal osteitis?
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protect the foot (pads/shoes)
rest from FORCED exercise stall confinement NOT necessary or desires |
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What is the prognosis of pedal osteitis?
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guarded
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Which animals are prone to develop pedal osteitis?
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animals worked on rough terrain
animals used in endurance competition |
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What is the most common cause of lameness?
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subsolar abscess
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What is a subsolar abscess?
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an abscess under the sole of the foot (anytime an animal is lame, this MUST be ruled out)
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T/F: subsolar abscesses usually cause mild lameness
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false: usually severe lameness is caused (sometimes very acute)
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Subsolar abscess: If drainage is not established, wounds close to the white line will drain where?
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at the coronary band (referred to as "gravel")
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Subsolar abscess: If drainage is not established, wounds of or close to the frog will drain where?
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at the heel
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How do you diagnose subsolar abscesses?
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-lameness (usually severe)
-incr rxn to hoof testers (means POSSIBLE subsolar abscess, though no response usually means NOT abscess) -incr rxn to tapping on hoof wall -incr pulse in digital arteries -discoloration - pare for purulent exudates - |
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Why not radiograph a possible P3 fracture right after it occurs?
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they are sometimes difficult to diagnose right after
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What is essential when healing a subsolar abscess?
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ventral drainage must be established (be careful using a hoof knife as the corium of the hoof wall may prolapse and prolong healing - can drill through the hoof wall as an alternative)
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What do you do if a subsolar abscess is draining at the coronary band?
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establish ventral drainage
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How long must drainage be maintained with a subsolar abscess?
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until the corium of the sole is healthy - approx 1 week
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What is suggested for a subsolar abscess after drainage is established?
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wet bandage w/mild antiseptic and a hypertonic soln (ex magnesium sulfate + a mild antiseptic in water)
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With subsolar abscess, when is antibiotic therapy suggested
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in immature animals and in complicated infections to prevent osteomyelitis (not necessary in mature horses w/a routine foot abscess)
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With what disease/problem is tetanus prophylaxis very important? When and how is it done?
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subsolar abscesses
if never had tetanus vaccination: consider toxoid and antitoxin (though antitoxin contraindicated in horses >2yrs) if tetanus vaccinated: give 2 doses of tetanus toxoid w/o antitoxin |
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Prognosis of subsolar abscesses
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good when ventral drainage is established prior to involvement of deeper tissues
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Sheared heels is aka...
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wry heels
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What are sheared/wry heels?
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marked difference in the length of the hoof wall at the heels resulting in variation of the pressure applied to each side of the foot
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What causes sheared/wry heels?
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improper footwear or trimming (poor shoeing)
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What should be done if you find sheared/wry heels but no lameness exists?
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probably best to shoe the horse so as to not worsen the condition, but not try to correct it
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What should be done if you find sheared/wry heels and the animal is lame?
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balance the foot- trim so that in time, weight will be born evenly on the medial and lateral hoof walls
apply a bar shoe and trim the elevated hoof slightly more so that weight is not born on that portion but on the frog and the contralateral side |
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Prognosis of sheared/wry heels
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no lameness- little significance
lame- fair prognosis |
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What are contracted heels?
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heels are closer together than normal
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What can cause contracted heels?
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usually the result of the animal not bearing adequate weight on heels- due to pain, being shod w/an overly long foot (as with gaited horses), 2ndary to nonweight bearing lameness or cast application
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T/F: increasing frog pressure if the key to treating contracted heels
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false: that was recommended in the past, but has found to be untrue
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What should be done in a horse with contracted heels but no lameness exists?
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take measure to prevent the problem from worsening
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How do you treat contracted heels?
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-if nonweight bearing due to pain, identify underlying cause and tx
-proper trimming to reduce length of the heel and balance the foot -shoe so that the shoe is slightly wide at the quarters and heels and the heel of the shoe extends to the rear of the foot -apply slipper shoes -thin the quarters (in severe cases) -grooving (in severe cases) |
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What are slipper shoes?
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the shoe is thicker on the axial sides so that when weight is born the hoof wall moves slightly abaxially
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What is grooving?
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a cast cutter is used to cut down to the whtie line
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Prognosis for contracted heels
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good if primary cause can be identified and corrected
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How would you prevent contracted heels?
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proper trimming and weight bearing
in horses that need to have a long foot (gaited horses) consider the use of a Chadwick spring |
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What is a Chadwick spring
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it is inserted in the sulcus of the frog under a pad and provides continual pressure in an abaxial direction
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What is the navicular apparatus made up of?
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navicular bone
collateral ligaments of the navicular bone distal sesamoidean ligament (aka impar ligament) navicular bursa deep digital flexor tendon distal annular ligament |
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What is navicular disease?
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a complex syndrome involving the navicular apparatus
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What age group is most commonly affected by navicular disease?
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ages 4-9 (middle age)
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What breed is most commonly affected by navicular disease?
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quarter horses
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What sex is most commonly affected by navicular disease?
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geldings
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2 possible causes for navicular disease
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abnormal mechanical forces- hard work, small feet in proportion to body size, upright pasterns and shoulders
circulatory disturbances- once thought that ischemia due to capillary thrombosis was a major factor, but this is now known to be of minimal significance |
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In which foot/feet is navicular disease usually found?
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most always a front foot lameness
usually bilateral w/one foot mroe severely involved |
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c/s of navicular disease
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short, choppy gait (rider reports "rough riding") - short anterior phase of stride
owners reports horse has sore shoulders foot worn excessively at toe horse tends to stumble horse points the foot |
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Why does the owners report sore shoulder on a horse with navicular disease?
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a myositis of the Brachiocephalicus muscle is common causing the horse to respond to pressure proximal to the shoulder
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Why does the horse stumble w/navicular disease?
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it moves with the foot very close to the ground
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How do you dx navicular disease?
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-typical gait (short anterior phase, foot close to ground)
-incr rxn (hoof testers across the heel from the wall to the frog; pressure applied to brachiocephalicus muscle) incr lameness (on hard surfaces, turns, following hoof testers, following digital flexion) |
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Which blocks can be used to help dx navicular disease? Are they specific enough?
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-palmar digital nerve block at the level of the lateral cartilages (heel block)
-injection into the distal interphalangeal joint (after heel block if it gets a positive response) no, not specific enough |
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What % of animal w/navicular disease do not have radiographic signs? Many of those animal w/radiographic signs are what?
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50%
sound |
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What are some typical radiographic signs of navicular disease?
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-lollipop-like appearance to the vascular channels on the distal border (normal channels are cone shaped)
-spurs or periosteal proliferation on the lateral borders of the navicular bone where the suspensory (collateral) ligaments of the navicular bone attach -incr size of synovial fossa |
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How could a gamma camera be used to look for navicular disease?
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look for an incr amount of isotope gathered (incr amount of radioactivity)
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How do you manage navicular disease in an animal that does NOT have to perform athletically?
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no tx necessary
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How do you manage navicular disease with shoeing?
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-trim foot to correct balance problems
-trim or shoe foot to maximize heel expansion and aid in break over -egg bar shoes could minimize tension on the DDF tendon |
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Name the most frequently used NSAID used for navicular disease
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Phenylbutazone (max dose 8.8mg/kg/day - long term dose cut in half)
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T/F: NSAIDs are much more toxic to ponies than horses
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true, so use a dose approximately 1/2 that of horses
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What can you use if an animal wil not take oral NSAIDs for navicular disease?
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Boswella- an herbal anti-inflammatory
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What does isoxsuprine hydrochloride do for navicular disease? What animals do not respond to it?
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incr blood flow as a result of vasodilation or altering the malleability of RBCs
those w/severe radiographic changes |
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How can sodium hyluronate be given to get a good result in navicular disease?
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by injecting it into the coffin joint and IV injection
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Name 3 long-lasting corticosteroids that can be used for either intra-articular therapy or intra-bursal therapy for navicular disease
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Celestone soluspan (Betamethasone)
Depo-Medrol (Methylprednisolone acetate) Vetalog (Triamcinolone acetonide) |
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Name2 short/medium lasting corticosteroids that can be used for either intra-articular therapy or intra-bursal therapy for navicular disease
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Flucort (Flumethasone)
Predef 2X (Isoflupredone acetate) |
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In what joint is intra-articular corticosteroid therapy done for navicular disease?
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distal interphalangeal joint
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In what bursal is intra-bursal corticosteroid therapy done for navicular disease?
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navicular bursa
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Drugs or procedures used to decrease nerve conduction in navicular disease last for how long?
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3 to 6 months
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Why should you not use percutaneous injections of ethyl alcohol in navicular disease?
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can result in painful neuroma formation
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name some drugs that can be used to decr nerve conduction in navicular disease and how would you use each of them?
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Ethyl alcohol- only used after sx exposing the nerve and inj into neurolemma
Sarapin- inj percutaneously (over the nerve) w/corticosteroid Cobra venom- inj percutaneously Dicumerol/Warfarin- inproves blood flow, can cause bleed out Adequan/polysulfated glycosaminoglycans Skelid/Tiludronate- alters bone remodeling |
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name 3 procedures that can be used to manage navicular disease
read how to do each of these (pg 2-14/15) |
percutaneous freezing of palmar digital nerves (casues white hair growth)
palmar digital neurectomy desmotomy of the suspensory/collateral ligaments of the navicular bone |
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What are you worried about cutting when doing a palmar digital neurectomy?
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the ligament of the ergot, thinking it is the palmar digital nerve
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When doing a palmar digital neurectomy, how do you differentiate between the palmar digital nerve and the palmar digital artery?
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the artery is elastic and the fibers of the nerve can be palpated
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What is the most common technique used to manage the nerve when doing a palmar digital neurectomy?
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the guillotine technique (apply tension to the nerve and cut as far proximal as possible, then cut distally to remove a 2-3 cm segment of the nerve)
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What other techniques can be used to manage the nerve when doing a palmar digital neurectomy?
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electrocoagulation of the proximal nerve end
epineural sheathing (aka epineural capping) laser drill a hole in proximal phalanx and insert proximal nerve end in the hole two incision technique |
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Where is a bandage applied after doing a palmar digital neurectomy?
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from the hoof to carpus (stall rest w/leg in bandage for 1 month)
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T/F: Initial reports of the effectiveness of a desmotomy of the suspensory/collateral ligaments of the navicular bone, as well as long term reports, were very encouraging with a 70-80% success rate
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False: while initial reports were encouraging, the long term effects are not as encouraging - usually results in an INITIAL reduction or correction of lameness
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T/F: desmotomy of the suspensory/collateral ligaments of the navicular bone can be done either standing or in lateral or dorsal recumbency
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false: desmotomy of the suspensory/collateral ligaments of the navicular bone can only be done in dorsal recumbency while a palmar digital neurectomy can be done either standing or in dorsal or lateral recumbency
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When doing a desmotomy of the suspensory/collateral ligaments of the navicular bone, what ligament are you going to transect?
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the collateral distal sesamoidean ligament
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How do you manage the leg/horse after doing a desmotomy of the suspensory/collateral ligaments of the navicular bone?
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bandage and stall rest until the sutures are removed in 10 days
some say slow return to work over 3 months, some say rapid return |
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What is a perivascular sympathectomy and fasciolysis?
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a technique used to tx navicular disease in which the sympathetic nerve supply to the medial and lateral digital arteries is stripped
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Where is a perivascular sympathectomy and fasciolysis performed?
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over the length of the proximal sesamoid bones w/the arteries being freed from their perivascular tissues
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What is the result of a perivascular sympathectomy and fasciolysis supposed to be?
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it is supposed to result in vasodilation of the region and return horses w/navicular disease to soundness
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T/F: navicular disease cannot be cured
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true: all methods just allow the animal to perform WITH the condition
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How do you prevent navicular disease?
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well-balanced shoeing
judicious use |
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Where do fractures of the navicular bone mainly occur? Are they common or rare?
Name the 4 types of fractures |
more commonly in forelimbs
quite rare avulsion, frontal, comminuted, simple body fractures |
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What are most fractures of the navicular bone a result of?
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trauma (excessive and repetitive loading), though sometimes associated w/navicular disease
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What c/s can be used to help dx fractures of the navicular bone?
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marked incr in pain and lameness on turning
marked rxn to physical dx tests for navicular disease |
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what is definitive for fractures of the navicular bone?
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radiographs- care must be taken to prepare and pack the foot to prevent artifacts
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What can be confusing on radiographs of a fracture of the navicular bone?
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a bipartite navicular bone (2 ossification centers)
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What are the two types of management for fractures of the navicular bone?
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conservative and surgical
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What does conservative management entail with fractures of the navicular bone?
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elevated bar shoe- stall rest (4-6 mos), small paddock exercise (additional 6 mos)
fiberglass cast w/the limb in marked flexion (6 mos) |
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What does surgical management entail with fractures of the navicular bone?
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insertion of a lag screw- requires special aiming devise, 6-8 mos rest, and neurectomy
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What percentage of horses with fractures of the navicular bone return to soundness?
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68%
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What is the prognosis for horses with fractures of the navicular bone with both conservative and surgical management?
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conservative- guarded for pleasure horse riding
surgical- guarded for athletic competition |
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How should acute laminitis be treated?
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AS AN EMERGENCY!! (to delay is very bad news)
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Why treat acute laminitis early?
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early tx --> early recovery --> better prognosis
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What is chronic laminitis?
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chronic to acute foot pain associate w/prolonged abnormalities in the lamina
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how is chronic laminitis developed?
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-exists when animals have not responded to therapy for acute laminitis
-some animals have developed laminitis, especially as a result of being on lush pasture, that takes a chronic course from the start |
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T/F: laminitis is more common in a pony than a horse
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true
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What is the ideal bedding for horses, especially those with laminitis?
|
turf (ex golf course), peat moss
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c/s of chronic laminitis
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-marked foot pain of prolonged duration
-3rd phalanx peaking thru the toe of the hoof wall) -"sinker"- meaning the whole 3rd phalanx sinks in the hoof and "bottoms out" |
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In which feet is chronic laminitis most common?
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more common in front feet
sometimes all 4 feet seldom, if ever, only rear feet |
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How do you dx chronic laminitis?
|
hx of acute laminitis
marked evidence of foot pain (reluctance to move, incr reluctance to turn, incr digital pulse, resists picking up foot, marked rxn to hoof testers, marked rxn to tapping on foot) |
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What could sand/styrofoam under the hooves do for chronic laminitis?
|
distributes pressure from wall to the hoof to even out pressure on the toe and sole
|
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How would you manage chronic laminitis?
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-judicious use of NSAIDs
-maintain normal BP -nursing care (comfortable stall, nonirritable bedding), adequate but not excessive feed) -sx |
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How could you surgically manage chronic laminitis?
|
-frog/heart bar shoes or wood shoe/"clog"
-trimming the foot so the sole is parallel to the distal aspect of the 3rd phalanx -removal of the dorsal hoof wall (grinding down of the toe so the anterior surface of the hoof is parallel to the anterior surface of P3 aka "beveling the toe") -completely remove full thickness of the hoof at the toe |
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What does removal of the dorsal hoof wall do for chronic laminitis? What shoe is recommended to support the hoof after these techniques are used?
|
allows the hoof to grow down parallel with the anterior surface of P3
bar shoe with clips |
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What does a deep digital flexor tenotomy do for chronic laminitis?
|
markedly reduces the pressure on the lamina at the toe and pressure of the third phalanx against the corium of the sole
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T/F: after a DDF tenotomy and adequate recovery time, a horse will be sound for any type of work/labor
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fales: following this procedure, a few horses will be sound for pleasure riding but in general one should only hope for pasture soundness
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When considering a DDF tenotomy to tx chronic laminitis, what should be done prior to surgery?
|
horse should be shod with a trailer shoe
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Where on the leg can a DDF tenotomy for chronic laminitis be done?
|
either at midpastern or midcannon (metacarpus)
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What are the advantages of doing a DDF tenotomy midmetacarpus/midcannon bone when dealing with chronic laminitis?
|
can be performed with the horse standing
tendon sheath is not invaded some support of the distal interphalangeal join is maintained less chance of postoperative infection |
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What direction and where is the incision made when doing a DDF tenotomy midmetacarpus/midcannon bone for chronic laminitis?
Why is it made there? |
a vertical incision is made on the lateral edge of the DDF at the junction of the middle and proximal thirds of the metacarpus
there is no tendon sheath in this area (between the carpal sheath and the great digital sheath) |
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What do you need to separate the DDF from when doing a DDF tenotomy midmetacarpus/midcannon bone for chronic laminitis?
|
separate from the superficial flexor and the neurovascular bundle
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What is the problem - when doing a DDF tenotomy midmetacarpus/midcannon bone for chronic laminitis - with doing this technique with the animal bearing weight on the leg?
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must be done blind
greater chance of incision the neurovascular bundle- primary blood supply to the distal limb involves the medial palmar artery!! |
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When would you normally do a DDF tenotomy at the midpastern area when treating chronic laminitis?
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normally only when a second tenotomy is indicated bc it is more difficult to perform in this area
|
|
In which direction and where do you make the incision when doing a DDF tenotomy at the midpastern area for treating chronic laminitis?
|
make a vertical midline incision in the palmar pastern through the skin and flexor tendon sheath
|
|
In which approach to a DDF tenotomy (midmetacarpus or midpastern) do the tendon ends separate farther and why?
|
midpastern because there is no attachment to supporting structures
|
|
What type of nerve block do you do when doing a DDF tenotomy at the midpastern area when treating chronic laminitis?
|
an abaxial sesamoid nerve block
|
|
What is the prognosis for a DDF tenotomy done for chronic laminitis?
|
guarded
reduction of pain and allows for derotation of P3 long and painful recovery from the laminitis, NOT from the surgery |
|
What is the result of an inferior check ligament desmotomy for treating chronic laminitis?
|
reduction in the pull of the DDF tendon on P3
animals can be expected to perform athletically following this procedure |
|
What is the prognosis for chronic laminitis?
|
always guarded
|
|
What do hoof cracks look like and how are they described/characterized?
|
fissures that usually run parallel to the laminae
some are surface cracks, some are perforating described according to their location and direction |
|
What are the descriptive/characterizing terms for hoof cracks?
|
toe, quarter, heel, and transverse (perpendicular to the laminae)
|
|
What can cause hoof cracks?
|
poor horn quality
thin hoof walls abnormal hoof angles long hooves |
|
Long hooves causing hoof cracks are more of a problem in... ?
|
gaited horses, where long hooves are maintained to cause a desired gait
|
|
Where do distal hoof cracks originate, do they cause lameness, and what is the problem with them?
|
originate at the bearing surface
don't usually cause lameness if cared for might become deeper (perforating) --> involve lamina --> lameness |
|
Where do proximal hoof cracks originate and what are they usually caused by?
|
originate in the coronary band
caused by trauma or scar tissue at the coronary band |
|
T/F: Only distal hoof cracks may extend the entire length of the hoof
|
false: proximal or distal hoof cracks can extend the entire length in time
|
|
How do you get hoof cracks that extend the entire length?
|
excessive hoof wall stress as a result of an overly long hoof or poor shoeing practices (may result in perforating cracks)
long shoeing intervals |
|
C/s with superficial hoof cracks
|
just a slight crack in the hoof wall with no indication of pain
application of hoof tester does not cause a response |
|
C/s with perforating hoof cracks
|
routinely cause lameness and response to hoof tester
|
|
How do you manage a superficial hoof crack?
|
-cutting a horizontal groove slightly proximal to the crack that extends to the white line
-drilling a hole at the proximal extension of the crack down to the white line -cross nailing- horseshoe nails driven parallel to the bearing surface across the crack |
|
How are these types of management of superficial hoof cracks helpful?
|
they distribute pressure more evenly
|
|
What is a perforating hoof crack?
|
one that extends to the lamina
|
|
How do you manage perforating hoof cracks?
|
stabilize it
|
|
How do you stabilize a perforating hoof crack?
|
-hoof wall adjacent to crack cleaned w/burr and dremel tool
-hoof acrylic -metal of leather patch |
|
Describe how you would use hoof acrylic to stabilize a hoof crack
|
drill holes in hoof wall --> lace wire or fiberglass across crack --> apply acrylic to hoof wall incorporating wire/fiberglass
--if hoof wall removal involved sensitive tissue, tx for several days until would is dry (place drain next to sensitive tissue and then apply acrylic) |
|
Describe how you would use a metal or leather patch to stabilize a hoof crack
|
a plate of metal or strip of shoe leather is fastened to each side of the crack with metal screws
|
|
What is another way to manage a perforating HEEL crack?
|
application of a bar shoe and trimming the hoof caudal to the crack so that no weight is born on the hoof wall caudal to the crack
|
|
Are horizontal crack pathogenic or non-pathogenic?
|
non-pathogenic
|
|
What is the prognosis for hoof cracks?
|
prognosis is generally good, but perforating cracks with a defect in the coronary band sometimes persist for life
|
|
How do you prevent hoof cracks?
|
proper foot care
|
|
What is a keratoma?
|
a tumorous mass that develops in the dorsal aspect of the hoof wall (consists of poor quality horn)
|
|
What is thought to cause a keratoma?
|
it is thought to start as an inflammatory reaction possibly due to trauma at the coronary band
|
|
What are the c/s of a keratoma?
|
-bulging of the hoof wall beginning at the coronary band
-not painful initially but becoming painful as the mass grows and puts pressure on the lamina -sometimes assoc w/chronic foot abscesses -occasionally assoc w/ development of conical plugs of abnormal horn extending upward from the sole surface |
|
How can you diagnose keratomas?
|
abnormal swelling of the hoof wall
sometimes abnormal conformation of the white line radiographs |
|
What could you see on radiographs of a hoof with a keratoma?
|
sometimes show a lytic area involving P3
|
|
How should you manage a keratoma?
|
removal of the hoof wall over the keratoma and debride to completely remove all abnormal tissue
|
|
Describe how you would remove the hoof wall when managing a keratoma
|
anesthetize patient or foot (can be done standing) --> Eschmarch bandage --> make vertical cuts in wall on either side of involved area w/cast cutter --> grasp distal surface w/hoof nippers and elevate hoof wall (completely remove it)
|
|
Describe what you'd do after removing the hoof wall when managing a keratoma
|
debride all abnormal tissue --> bandage wound to control hemorrhage --> remove Eschmarch bandage --> apply bar shoe w/clips to stabilize wall --> maintain wound under bandage until wound healthy --> reshoe every 6 wks until hoof grows down to bearing surface
|
|
When removing the hoof wall (managing a keratoma), approximately how long iwll it take until the hoof grows back down to the bearing surface?
|
approximately 9 months
|
|
What is the prognosis for keratomas?
|
83% success rate
should show marked/quick improvement of the animal's demeanor |
|
What can cause an infection of the navicular bursa?
|
puncture wounds through or close to the frog
|
|
What are infections of the navicular bursa sometimes associated with?
|
subsolar abscesses
|
|
How can you tell the difference between a subsolar abscess that might involves the navicular bursa and a subsolar abscess that does NOT?
|
-if the abscess is drained and there is still significant lameness --> possible involvement of the navicular bursa
-if the abscess is drained and the animal shows a marked reduction in lameness w/i a day or (at the most) 2, most likely no navicular bursa involvement |
|
T/F: a puncture wound through or close to the frog does not always result in involvement of the navicular bursa
|
true
|
|
How do you dx an infection of the navicular bursa?
|
evidence of a puncture would near or through the frog
persistent and severe lameness following the drainage of a subsolar abscess in the area of the frog |
|
What is an Eschmarch bandage?
|
it is a rubber tourniquet
|
|
How would you drain the navicular bursa if it were infected?
|
clean and trim foot --> wet antiseptic dressing overnight --> anesthetize & eschmarch bandage --> cut a window approx 2.5cm square in the frog halfway between dorsal and palmar/plantar aspect --> dissect down to the DDF tendon and cute a window in it --> flush the bursa
|
|
How would you close the holes made in the foot after draining the navicular bursa?
|
pack defect in DDF tendon and frog w/antiseptic gauze (infused with iodoform) --> maintain sterile dressing until defects fill to close the bursa
|
|
T/F When you flush the navicular bursa bc of infection, you expect only a small amount of purulent exudate
|
true bc the bursa is quite small
|
|
What may be required to make the horse sound after draining the navicular bursa of infection?
|
a palmar digital neurectomy
|
|
What is considered the best technique for draining the navicular bursa of infection?
|
arthroscopic guidance
|
|
T/F: when using the arthroscope to drain the navicular bursa of infection, you also go through the frog
|
true
|
|
T/F: animals have a better prognosis when using the classical technique to drain the navicular bursa of infection
|
false: better prognosis when using the arthroscopic technique
|
|
What technique(s) is said to possibly cure an infection of the navicular bursa?
|
early diagnosis and use of regional limb perfusion (however, there are no reported results/studies for this)
|
|
Prognosis of an infection of the navicular bursa when using the classic street nail procedure and the arthroscopic flushing technique
|
classic- 33% (neurectomy commonly required)
arthroscope and flushing/lavage- 75% |
|
When is the prognosis for an infection of the navicular bursa the best?
|
when it is caught early and the arthroscopic technique is used
|
|
List the 6 types of fractures that could occur in the 3rd phalanx
|
I Abaxial fractures w/o joint involvement
II Abaxial fractures w/joint involvement III Axial fractures w/joint involvement IV Fractures of the extensor process V Multifragment fractures w/joint involvement VI Solar margin fractures |
|
Which feet are most commonly involved with P3 fractures?
|
front feet
|
|
How can one get a P3 fracture?
|
acute trauma (kick against a hard nonmoveable structure
excessively hard or fast work |
|
What are the c/s of P3 fractures? What other problem does it resemble?
|
acute severe lameness- will also be fount in a foot abscess but a fx should be kept in mind
|
|
How do you go about diagnosing a P3 fracture?
|
soak the foot for a couple days (allows abscess to mature if that's what it is) --> no response --> consider radiographs --> take a number of views (esp in fx that don't involve the joint)
|
|
When evaluating a foot with acute severe lameness for a P3 fracture, why not just take radiographs the first day?
|
many times fracture lines are more easily detected a couple to 10 days after they occur (more displacement and osteolysis has occurred)
|
|
What are some different ways to manage a P3 fracture?
|
remove fragments
stabilize w/fiberglass cast stabilize w/bar shoe and clips, then stall rest compression screw just stall rest palmar digital neurectomy attach hoof to block of hard wood with hoof acrylic |
|
With what type of P3 fracture would you remove the fragment(s)?
|
possibility with type VI (solar margin)
|
|
With what type of P3 fracture would you stabilize it with fiberglass cast? What would you do following the cast?
|
types I and II (abaxial w/o and w/joint involvement) in young animals
apply a bar shoe and clips |
|
With what type of P3 fracture would you stabilize with a bar shoe and clips and stall rest? For how long?
|
type III (sagittal/axial fracture w/joint involvement) in animals < 3yrs
stall rest for 9 months |
|
With what type of P3 fracture would you apply a compression screw
|
type III (sagittal/axial fx involving the distal interphalangeal joint in animals >3 yrs
|
|
When placing a compression screw with a P3 fracture, what do you need to avoid?
|
foot vasculature and the coffin joint
|
|
When placing a compression screw with a P3 fracture, how long do you soak the foot in a wet antiseptic bandage? Before or after?
|
overnight
before |
|
T/F: placing a compression screw with a P3 fracture is done under general anesthesia
|
true
|
|
Describe the process of placing a compression screw for a P3 fracture
|
mark hoof wall where screw should go --> drill hole in wall to P3 --> pilot hole drilled thru P3 to fx using fluroscopic guidance of intraoperative radiographs--> drill sleeve inserted, then smaller bit --> when small bit reaches far side of P3, remove and the far segment is tapped and the screw inserted and tightened
|
|
When placing a compression screw for a P3 fracture, what do you do once the screw is in?
|
take radiographs to make sure the screw doesn't protrude into lamina, then packthe defect in the hoof wall with antibiotic impregnated polymethylmethacrylate
then shoe for bar shoe and clips and stall rest for 6-9 months |
|
With which type of P3 fracture could you just stall rest? For how long?
|
type VI (solar margin) (moreso than fragment removal, I think)
4 months |
|
With a P3 fracture, when/with which type of fracture would you possibly do a palmar digital neurectomy on the side of the fracture?
|
for type I fractures (abaxial w/no joint involvement) in animals that are in training that must continue
|
|
How do you manage P3 fractures in foals and weanlings?
|
stall rest of attaching the foot to a block of hardwood w/hoof acrylic 9Equilox) is usually adequate
|
|
Prognosis of P3 fractures
Exception? |
good w/proper management in animals < 3yrs
guarded in older animals for return to competition exception: type V |
|
What type of fracture involves the extensor process of P3?
|
Type IV
|
|
What could cause a fracture of the extensor process of P3?
|
hyperextension
avulsion as a result of stress by the extensor tendon separate center of ossification |
|
T/F: most commonly animals with a ffracture of the extensor process of P3 have no c/s and it's only an incidental finding on a radiograph
|
false: most commonly an animal is lame, but sometimes no c/s are present and the finding is incidental
|
|
How would you confirm a dx of a fracture of the extensor process of P3?
|
radiograph
|
|
how should you manage a fracture of the extensor process of P3 with small chips?
|
they would routinely be removed w/the aid of an arthroscope
|
|
How could you manage a a fracture of the extensor process of P3 with large chips or fragments?
|
there is no definite rule:
-conservative- stall rest -remove small fx -stabilize larger fx with screw |
|
What is the problem with using the conservative tx for a fracture of the extensor process of P3?
|
stall rest runs the risk of developing low ring bone
|
|
How would you remove fragments of a fracture of the extensor process of P3 with an arthroscope?
|
the arthroscope and isntrument portals are usually on opposite sides of the common or long digital extensor tendon
|
|
What is/are the problem(s) of trying to stabilize a fracture of the extensor process of P3 rather than remove it?
|
exposure is limited which makes it difficult, so it routinely requires an arthrotomy
it is difficult to place more than one screw and if the stabilization is not complete there is a good chance there will be boney proliferation (aka low ring bone) |
|
What would help when stabilizing a fracture of the extensor process of P3?
|
thinning the proximal hoof wall with a rasp so that it is possible to make an incision through the proximal hoof wall to gain better access to the extensor process
|
|
What is the prognosis with a fracture of the extensor process of P3?
|
fairly good if small fragments can be removed
guarded with fragments that, bc of their size, have to be stabilized |
|
Give the other names for periostitis of the extensor process of P3
|
Low Ring Bone
Buttress Foot Pyramidal Disease |
|
What is periostitis of the extensor process of P3?
|
a periosteal proliferation secondary to fractures of the extensor process or hard work on hard surfaces
involves the coffin joint (?) |
|
What can cause periostitis of the extensor process of P3
|
trauma resulting in fracture of the extensor process
inflamm of the attachments of the joint capsule to the extensor process and/or the 2nd phalanx and secondary periostitis |
|
What will you see with periostitis of the extensor process of P3?
|
chronic lameness
boney proliferation that sometimes is extnesive which causes bulging of the anterior hoof wall (a "buttress" like appearance) |
|
How can you dx periostitis of the extensor process of P3?
|
chronic lameness
lameness decreases w/a foot block radiographs showing boney proliferation |
|
How do you manage periostitis of the extensor process of P3?
|
there is no effective management
|
|
What is the prognosis for periostitis of the extensor process of P3?
|
poor for return to athletic performance but the animal should be pasture-sound w/no therapy
|
|
How could you prevent periostitis of the extensor process of P3?
|
early removal of any chip fx of the extensor process
if possible, refrain from hard work on hard surfaces |
|
What is the condition known as side bones?
|
ossification of the lateral cartilages
|
|
What causes side bones?
|
usually thought to be associated w/hard work in heavy horses
part of the natural aging process (though sometimes present in young animals) |
|
Are side bones reported to be more common mares, stallions, or geldings?
|
mares
|
|
Which cartilage is most commonly affected: the lateral lateral cartilage or the medial lateral cartilage?
|
the lateral lateral cartilage
|
|
What could you see (c/s) with side bones?
|
many times it is an incidental finding on radiographs w/no lameness present
animal is sometimes lame during ossification occasionally the ossified lateral cartilage fractures |
|
An apparent fracture in side bones is sometimes due to what?
|
two centers of ossification
|
|
How do you dx side bones?
|
lameness
pain on palpation of the cartilage radiographs showing ossification scintigraphy showing uptake of a radiopharmaceutical |
|
What gives a definitive diagnosis of side bones?
|
scintigraphy showing uptake of a radiopharmaceutical plus pain and radiographic evidence of ossification
|
|
T/F: Ossification of side bones cannot be stopped once it's started
|
true
|
|
How do you manage side bones?
|
-feet should be carefully examined for balance and any imbalance corrected
-toe should be rolled/trimmed so that breakover point is moved caudally -expansion of the heels should be encouraged -small fractures removed |
|
How do you encourage heel expansion when treating side bones?
|
slipper shoes
leaving the most caudal nail out so the heels can move |
|
How do you remove small fractures of side bones?
|
by making an incision over the cartilage (horizontally and parallel to the coronary band)
|
|
With side bones, What do you do if you find large fractures?
|
they should NOT be removed
if they are causing a problem, they usually respond to prolonged periods of rest (4-6 months in a stall or small paddock) |
|
Can you see large fractures of side bones on a radiograph?
|
they are usually always visible bu surrounded by considerable proliferative bone
|
|
What is quittor?
|
infection and then necrosis of the lateral cartilage
|
|
What is the most common cause of quittor?
|
most commonly results from a wound involving the lateral cartilage
|
|
What could quittor be a complication of? is it likely? Why/why not?
|
a subsolar abscess
unlikely bc a subsolar abscess that is not drained ventrally usually breaks out at the coronary band w/purulent material following a tract between the sensitive and insensitive lamina which is abaxial to the lateral cartilage. |
|
What are the c/s of quittor?
|
chronic draining tract associated w/an infection of the lateral cartilage
|
|
How can you dx quittor?
|
obvious involvement of the lateral cartilage
enlargement of the area w/draining tract(s) from the infected cartilage |
|
Name the biggest problem w/quittor
|
the infected cartilage WON'T heal bc cartilage has minimal blood supply and as a result minimal resistance to infection
|
|
What is the only solution to quittor?
|
surgical removal of all diseased cartilage
|
|
Explain how you remove all the diseased cartilage
|
anesthetize animal & apply eschmarch bandage --> infuse dilute methylene blue into draining tracts to identify diseased cartilage --> maximally extend coffin joint to retract joint capsule and minimize chance of dissecting the joint --> incise over proximal aspect of the involved cartilage and remove all diseased tissue
|
|
Is it common in quittor that the diseased cartilage extends distally to the coronary band? What do you do when surgically removing that diseased cartilage?
|
yes, it's common
the hoof wall must be thinned or a hole drilled in it so that all the diseased tissue can be removed and ventral drainage established |
|
What is the most important thing to remember when doing a surgery for quittor?
|
preserve the coronary band!!
|
|
prognosis for quittor
|
depends to a degree on the amount of cartilage involved
|
|
How do you prevent quittor from happening?
|
prevent penetrating wounds involving the lateral cartilage
treat wounds in this area aggressively with adequate antibiotic support and ventral drainage |
|
What are the four types of fractures that can occur in P2?
|
small chip fx
palmar/planter eminence fx axial fx comminuted fx |
|
What is the most common cause of a P2 fracture?
|
abnormal internal stress (not commonly associated w/trauma)
|
|
A P2 fracture is most commonly seen in what animals? Why?
|
horses used for western games
they are asked to turn at high speed, slide, and stop quickly their shoes are commonly modified to increase traction |
|
What else can cause a P2 fracture?
|
also seen when an animal is first turned out after a long period of confinement (never a good idea to turn animals so they can run at will after being confined)
|
|
70% of P2 fractures occur in what limb(s)?
|
hindlimbs
|
|
Which type(s) of P2 fractures can cause a severe leg carrying lameness (animal does not bear weight on the limb) and causes a marked instability?
|
comminuted fx
|
|
How would you diagnose a P2 fracture?
|
chip fx and eminence fx show varying degrees of lameness, so they would be detected on radiograph following lameness workup
|
|
Why is diagnosing a comminuted P2 fracture quite obvious?
|
because of the marked instability
radiographs are taken to better determine prognosis and to decide method of repair |
|
T/F: few full sized horses with complete fractures of the radius, ulna, and femur have been treated successfully
|
false: few full sized horses with complete fractures of the radius, TIBIA, and femur have been treated successfully
|
|
T/F: with the continued development of improved methods and nursing care, successful repair of a radius, tibia, or femur fracture of likely
|
false: successful repair is possible, but NOT likely
|
|
What do you need to consider with animals that have radius, tibia, or femur fx?
|
euthanasia
|
|
When moving an animal with a fracture limb, when will you give analgesia?
|
only after the fx is stabilized bc if it is used prior to stabilization, analgesia encourages movement and this usually results in more damage
|
|
Where and how do you stabilize a limb fracture?
|
joints above and below the fx should be stabilized
end of splints or casts must extend well beyond the fx don't allow the end of the splint to be in the middle of a diaphysis |
|
Fractures of what 2 bones would you not apply a splint to? Why?
|
humerus and femur
splints applied to these generally cause increased motion at the fx site |
|
What can be used to stabilize the limb fracture when moving an animal?
|
Robert Jones Bandage
splint over robert jones bandage |
|
What is a Robert Jones Bandage?
|
a large bulky bandage that is applied by applying rather thin layers of padding under tight bandages
|
|
Describe how you make a Robert Jones bandage?
|
layer of cotton or towling
moderately tight bandage on the first couple layers succeeding layers of padding (1/2-1" thick) adequate bandage is approx 3 times the size of the leg and the binders are applied tight enough that you can "thump" the bandage with a finger |
|
Splints over a RJB are best applied how? A PVC piper could work as a splint when it is cut to what size?
|
at 90 degree angles
1/4" of the original diameter |
|
T/F: splints over a RJB must be tightly applied with unyielding material
|
true
|
|
Stabilization of which bones must include firm material and where should the splint be placed?
|
radius and tibia
on a high radial fracture, a firm splint must be on the lateral side |
|
When you trailer a horse with a limb fx, how should it be trailered?
|
with the fx leg to the rear (incase you slam on the breaks)
limit the movement of the animal by limiting the space don't turn the animal loose have a handler int he trailer slings can be helpful vans and stock trailers are best |
|
How can you best manage a fracture of the ulna?
|
with a splint that stabilizes the carpus so that the animal can bear weight on the limb (since the triceps is nonfunctional when its attachment to the ulna is compromised the animal cannot extend the carpus to allow weight bearing)
|
|
how would you best manage a chip fracture of P2?
|
arthroscopic surgery to remove the fragment
|
|
How would you manage a comminuted fracture of P2 involving the distal interphalangeal joint (coffin joint)?
|
the joint surfaces need to be reconstructed perfectly to regain soundness
|
|
What is the prognosis for a comminuted fx of P2 that involves the distal interphalangeal joint?
|
poor for return to athletic soundness (residual lameness is most likely)
|
|
What should be done for a fracture that involved only the proximal interphalangeal joint (pastern)?
|
arthrodesis (fusing the joint)
internal fixation a half limb cast |
|
What would you use for internal fixation in a P2 fracture that involved only the proximal interphalangeal joint (pastern)? Benefits?
|
remove the joint cartilage and stabilize with screws and plates
shorter recovery time |
|
What should the half limb cast include when stabilizing a P2 fracture that involved only the proximal interphalangeal joint (pastern)? how long does recovery take?
|
should include the foot and up to the proximal metacarpus/tarsus
6-8 weeks recovery w/or w/o internal fixation |
|
What do you need to check on with daily observation of a cast for stabilization of a fracture of P2?
|
is the animal more lame today than yesterday
is the cast intact is the limb above the cast swollen are there abnormal smells are the flies attracted to the cast is the animal alert, moving and eating as well as today as yesterday |
|
Prognosis if only the proximal interphalangeal joint is involved in a P2 fx
|
30% return to soundness
|
|
Which has a better prognosis: P2 fx in a forelimb or rearlimb?
|
rearlimb
|
|
What are some possible complications of a P2 fracture?
|
-the pressure applied by P1 could separate and displace the fx fragments
-considerable expense for a cast -development of laminitis of the supporting (good) leg |
|
How can you prevent P2 fractures?
|
-minimize the use of devices that incr foot traction
-exercise animals prior to turning them out when they have been stalled for a period of time |
|
What is osteochondrosis of the pastern joint usually associated with?
|
small cysts rather than cartilage flaps
|
|
What can cause osteochondrosis of the pastern joint?
|
problems with endochondral ossification
hereditary nutritional |
|
What are the c/s of osteochondrosis of the pastern joint?
|
mild lameness
|
|
How do you diagnose osteochondrosis of the pastern joint?
|
lameness w/positive flexion test that's blocked w/an abaxial sesamoid block or local anesthetic in the pastern joint
radiographic evidence |
|
What is the most common way to manage osteochondrosis of the pastern joint/
|
arthrodesis
|
|
What are the other ways you can manage osteochondrosis of the pastern joint?
|
curet the cyst- transosseus drilling through the phalanx w/fluroscopic guidance and then drilling out the cyst- difficult
intra-articular hyaluronan injections NSAIDS or steroids |
|
What is a High ringbone?
|
osteoarthritis of the proximal interphalangeal joint (pastern)
|
|
What can cause high ringbone?
|
relatively common in animals asked to make quick turns and stops
wear and tear- continual irritation due to stresses or poor conformation secondary to chip fractures and osteochondrosis of the joint |
|
In which animals might high ringbone be due to quick turns and stops?
|
Western performance horses
|
|
In which animals might high ringbone be due to secondary osteochondrosis of the pastern joint?
|
young horses
|
|
What are the c/s of high ringbone?
|
chronic lameness increased w/increased amount of work
advanced cases- boney proliferation that can be palpated reduced range of motion |
|
in high ringbone, where will you see boney proliferation in early cases?
|
at the sight of the joint capsule but not in the joint itself
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how do you dx high ringbone?
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chronic lameness
enlarged joint pain w/digital flexion and/or torsion localize pain w/abaxial sesamoid block (PD --> foot block --> abaxial sesamoid block) |
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How do you confirm high ringbone? What are the two types?
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radiographs
False Ringbone- periosteal reaction at the attachment of the joint capsule but NO joint involvement True Ringbone- preiosteal proliferation extends into the joint - usually a reduction of joint space |
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What can you do conservatively with high ringbone?
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NSAIDs
intra-articular corticosteroid if animal moves in a sound manner w/conservative therapy, continue until no longer effective |
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What can you do surgically for high ringbone?
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arthrodesis (surgical fusion) of the pastern joint
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What is ankylosis?
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natural fusion of the joint
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T/F: a functional pastern joint is not necessary for athletic soundness
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true
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Describe the simple technique for performing an arthrodesis for high ringbone
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skin incision on lateral and medial side of the joint at the level of the joint surface --> use a bone drill to destroy as much of the joint surface as possible
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What do you do after the simple arthrodesis technique for high ringbone? How long should this be done?
How long until the horse is sound? |
place the leg in a half limb cast (just below carpus/tarsus to and including the foot)
keep foot in cast and horse in stall for 8 weeks animal should be sound 4-6 months after sx |
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Where do you make the incisions for the more complex technique for doing an arthrodesis for high ringbone
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joint approached from dorsal midline --> longitudinal incision made in the common or long digital extensor tendon --> at prox and distal extent of incision make lateral incisions on opposite sides so the anterior surface of the joint is exposed
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For the more complex technique for doing an arthrodesis for high ringbone, what do you do once all the incisions are made?
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--> divide medial or lateral collateral ligaments so joint can be disarticulated --> all cartilage is removed from articular surfaces of P1 and P2
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once all the articular surfaces are free of cartilage,how do you stabilize the joint when doing the more complex technique for doing an arthrodesis for high ringbone?
How do you finish the procedure? |
stabilization is best with 5.5mm screws to compress the joint and a plate applied to the anterior surface of P1 and P2
collateral ligament and the common or long digital flexor tendon are repaired and a cast is required but for a much shorter time than with the simple technique |
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For how long is a cast required after doing the more complex technique for doing an arthrodesis for high ringbone?
What % actually become sound after this procedure? |
2-4 weeks
75% |
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how do you prevent high ringbone?
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judicioius use
early removal of chip fractures |
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In which directions does the pastern joint luxate or subluxate?
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dorsal or palmar
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In which animals does dorsal luxation/subluxation of the pastern joint occur bilaterally?
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in horses with upright conformation in the hindlimbs
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What can cause dorsal luxation/subluxation of the pastern joint?
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damage to the suspensory ligament or contracture of the distal sesamoidean ligaments
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What can cause palmar luxation/subluxation of the pastern joint?
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failure of the palmar supporting structures (distal sesamoidean ligaments and superficial digital flexor tendon) insertions
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What does the superficial digital flexor tendon do?
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prevents knuckling over (hyperflexion)
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What are the c/s of dorsal luxation/subluxation of the pastern joint?
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marked dorsal swelling over the interphalangeal joint
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What are the c/s of palmar luxation/subluxation of the pastern joint?
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hyperextension of the interphalangeal joint and sinking of the metacarpophalangeal joint
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How do you confirm diagnosis of luxation/subluxation of the pastern joint?
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radiographs
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How can you sometimes manage dorsal bilateral luxation/subluxation of the pastern joint?
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NSAIDS and controlled exercise
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What can you do if the conservative tx for dorsal subluxation of the pastern joint is in effective?
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arthrodesis of the interphalangeal joint
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What can you do to manage palmar subluxation of the pastern joint?
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arthrodesis of the interphalangea joint
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