Give a sysnonym for each of the following terms: proximal phalanx, middle phalanx, distal phalanx, distal sesamoid bone, middle distal sesamoidean lig
- proximal ph=long pastern bone=P1
- middle ph=short pastern bone=P2
- distal ph=coffin bone=P3
- distal sesamoid bone=navicular bone
- middle distal sesamoidean ligament=oblique sesamoidean ligament
Give a synonym for each of the following terms: palmar or plantar, interosseus tendon, superficial distal sesamoidean ligament.
- palmar or plantar=volar
- interosseus tendon=suspensory ligament
- superficial distal sesamoidean ligament=straight sesamoidean ligament
What is de facto proximal sesamoidean ligament?
The interosseus tendon is actually the proximal sesamoideal ligament
Which distal sesamoidean ligament spans over two joints?
Straight sesamoidean ligament
Why are the (proximal) sesamoid bones prone to fracture?
- due to stress placed on ligamentous sys. when body weight places downward force on fetlock joint in rapid motion
- sesamoids caught between suspensory ligament and distal sesamoidean ligaments
What is the meaning of plantigrade, digitgrade, unguligrade? Give examples of each.
- plantigrade=all of the foot (entire sole) is on ground; humans, bears
- digitigrade=stands on digital pads-camelids and carnivores
- unguligrade=stands on hoof; horses, cow, most ungulates
What are the three parts of the wall, what are the bars?
- toe, quarters, and heel
- the bar is where wall reflected invward and back towards toe (at heel)
What is the white line and how is it significant?
White line is the junction of the wall and sole. It is the spot where farriers place nails when shoeing.
What is the: frog, heel, bulbs, and coronet?
- frog=wedge-shaped, horny prominence in the sole of horses’ hooves (the space between the bar)
- heel=caudal part of hoof
- bulbs=caudal aspect of heel
- coronet=junction between skin and hoof
A hoof pick is used to clean maure and dirt out of the “bottom” of a horse’s foot. What deep groove(s) would the hoof pick be especially useful for?
-collateral sulci (paracuneal grooves) are deep grooves separating the bars from the frog that the hoof pick is especially useful for
What produces the hoof wall and how does outgrowth of the wall affect its flexibility?
- long conical papillae in coronary band produce tubular horn which forms buk of hoof wall
- toe grows out slowly b/c it’s long part of wall and therefore is oldest part of hoof wall
- as hoof wall ages it becomes less moist and therefore less flexible
What is the structure and function of the equine collateral cartilages of the coffin bone?
-collateral cart. are attached to wings of coffin bone and not to hoof. When foot strikes ground the digital cushion expands and pushes the collateral cartilages out so that veins are compressed forcing blood to move up leg
Why is the navicular bone so named?
It is shaped like a boat.
What are the principle attachments of the navicular bone?
Attached to long pastern by suspensory ligaments of navicular bone and distal sesamoidean ligament bands navicular to coffin bone
What is on the dorsal and palmar surface of it?
- dorsal suface in contact with palmar surface of coffin joint
- palmar surface in contact with navicular bursa
What is the main structure putting pressure of the navicular bursa?
Deep flexor tendon can put pressure on navicular bursa and may cause pain. A long toe will drop heel causing more pain due to tendons being pulled tight b/c of increased extension. An enlarged heel will reduce pain due to increased flexion.
What is the structure and significance of the digital cushion?
- similar to dig. pad in dog; made of collagen, adipose tissue, and hyaline cart.
- becomes squashed when weight is put on foot and compresses vein between hoof wall and cartilages and squeezes blood out of venous spaces that lie between skin/cart
Compare and contrast bovine foot w/ that of horse.
cows are diff. form horses b/c:
- bear weight on heel and wall; bov. heel separate from wall (part of wall in equ.-volar third); bov. heel homologous to bulbs of eq. heel
- bov. feet have wall and sole (no homol. of frog or collateral cartilages)
Compare and contrast bovine foot w/ that of horse (cont.)
cows are diff. from horses b/c/:
-laminae lack secondary (microscopic) laminae (prob. relates to fact that in horse wall bears all wgt. but in cattle >half of weight is borne by wall-thus laminitis in cattle not as painful)
