Large Animal Sx- Diseases of the Equine Foot (foot conformation and exam)

wilsbach's version from 2015-11-04 18:53


Question Answer
know the parts
(also groove between the bar and the frog is the paracuneal groove)
how does the coffin bone sit?doesnt sit on floor- actually is slung in the foot by the laminae (via the digital cushion of fibroelastic tissue)
the part between the wall of the hoof and the skin is the?coronet
parts of the wall anatomy
which structure makes most of the wall of the hoof?coronary dermis (with coronary papilla)
is P3 the top or bottom phalange?P3 aka coffin bone-- most distal
Where's the navicular bone?
Where's the DDFT (deep digital flexor tendon)
where is the digital cushion?
where is the tendon sheath for the foot?
label DDFT, semoidean ligaments, common digital extensor, superficial digital flexor, suspensory ligament
where is the impar ligament?the lig attaching the navicular bone to the coffin bone
where is the navicular bursa?between the navicular bone and the DDFT
where is the extensor process?on the top of P3
label these ligs, yo
Label these tendons, yo
what is the only flexor tendon which attaches to the coffin?the DDFT
how does the lateral wall of the hoof differ from the medial wall?Curve of lateral wall is wider than on the medial wall (since M is more sloped, L is wider)
how does the slope of the medial quarter differ from the slope of the lateral quarter?Slope of the medial quarter is steeper than slope of the lateral quarter (the letter M has 2 step peaks)
what are you more worried about, broken-back hoof-pastern axis, or broken foreward? why?broken back, because there is more stress on the back of the foot and on the navicular bone
what are the three types of Hoof-Pastern Axis, and what do they look like?Normal, broken back, and broken foreward. The back and forward is refering to how the hoof looks in comparison to the pastern-- the broken back looks like the hoof is sloped more backward
how can you assess Medial-Lateral Hoof Balance?compare the coronary band to the bottom of the foot- they should be parallel. if not there is a lot of torque forces affecting the foot negatively
what are hoof tests for/what do you use them for?they apply a strong pinch to the hoof. This is good for finding laminitis, navicular disease, hoof abscesses, etc
what are "clinches"? Why are they important?When you put nails into the hoof to apply the shoe, you hammer them outward so the tip of the nail sticks out...then you hammer this down into a little crimp. This is "clinching". You do this because if the nail goes too deep, it can hit sensitive structures and cause lameness
how do you remove a shoe?Elevate clinches with hammer and clinch cutter, OR file off clinches with a rasp. Then remove shoe with pullers or crease nail pullers (NOT NAIL NIPPERS), and ALWAYS PULL TOWARD THE TOE
*which way do you pull nails out of a shoe to remove it?always pull towards the toe (when holding the foot up, this is pulling them in a downward fashion)
explain how to trim a hoofUse nippers to remove wall, Starting at the bar and working around the foot. Then Pare sole and frog with hoof knife, and widen the sulci. Then rasp foot to remove the jagged edges.
where's the inferior check ligament?originates from the deep palmer carpal ligament and joins the deep digital flexor tendon at the middle of the metacarpus (cannon bone). This is the inferior check ligament. it is aka accessory lig of DDFT and is 10 on this diagram
where's the superior check ligament?aka Accessory lig. of SDF, starts on distal radius and connects to the SDF. This is #12 in this diagram

Diagnostic Aids

Question Answer
what are 5 things you should be palpating?(1) Palmar/Plantar digital arteries (are they bounding?) (2) DDFT and tendon sheath (3) Coronary band (4) Hoof wall (5) Collateral cartilages
before using hoof tester, always...pick foot totally clean
which areas should you test with the hoof testers?Test across toe, frog, individual heels, across both heels, and then COMPARE TO OTHER FOOT! tapping on foot can also be helpful, since it's kinda a diff pressure
Intra-articular/bursal anesthesia--> which two areas did he mention for this?Distal interphalangeal joint, Navicular bursa
Palmar Digital Nerve Block--> which anesthetic do you use?Mepivicaine (he also called it Carbocaine)
Palmar Digital Nerve Block--> where do you inject this?Medial and lateral neurovascular bundle, 25g needle is inserted just proximal to collateral (ungual) cartilages
Abaxial Sesamoid Block--> which anesthetic do you use?Mepivicaine (he also called it Carbocaine)
Abaxial Sesamoid Block--> where do you inject this?Medial and lateral neurovascular bundle, 25g needle is inserted at the level of the sesamoid base. "c" in diagram
how long should you wait after injecting for your block to know theyre good and numb?10-15min
Coffin Joint Block--> where do you inject for this?1 cm proximal to coronary band with needle perpendicular to the skin into the dorsal pouch (a on the diagram)
Navicular Bursa block--> how do you do this? aka?note: uncommon to do!! need Fluoroscopic/ Radiographic guidance and a 20G spinal needle. insert the needle between the heel bulbs. "Hickman block"
Standard Views for radiography of the hoof? (4)Lateromedial, 0° Dorsopalmar/plantar, 60° Dorsopalmar/plantar, Palmaroproximal-Palmarodistal 45° oblique (aka skyline)
an Additional view for radiography of the hoof is the 45° oblique. What does it help look at? what other methods can you combine with this?can look at M and L wings, helpful with Venogram, Bursography, Fistulogram
what is the Palmaroproximal-Palmarodistal 45° oblique view good for looking at?navicular bone- aka "navicular skyline"
what view is this? 0° Dorsopalmar/plantar
what view is this? Lateromedial
what view is this? Palmaroproximal-Palmarodistal 45° oblique
what view is this? 60° Dorsopalmar
how exactly do you go about taking a Palmaroproximal-Palmarodistal 45° oblique?
how do you go about taking a 60° Dorsopalmar view?
how useful is ultrasound for the foot? what can you use it for?limited applications in the foot, but good for looking at: Collateral ligaments of the coffin joint, Suspensory ligament of the navicular bone, Deep digital flexor tendon, and seeing through the frog/sole
Nuclear Scintigraphy basically lets you see...the "hot spots"-- lets you see where you should take your rads
Pros and cons of MRI?PROS: Soft tissue visualization in the foot, Target treatment, Early detection of disease, Severity of disease. CONS: Cost, +/-General anesthesia, Travel to referral hospital, Hospitalization