Pelvic Limb 5, Thoracic Limb 1 Flashcards
In the horse, what does the superficial peroneal n. supply?
Only cutaneous to distal limb
In the horse, what does the deep peroneal n. divide into and where does this happen?
medial and lateral dorsal MT nn. @ proximal cannon bone
In the horse, what runs bt the medial and lateral dorsal MT nn.?
long digital flexor tendon
In the horse, where do the medial and lateral dorsal MT nn. run to?
all the way to the coffin joint
In the horse, what does the tibial n. divide into and where does this happen?
medial and lateral plantar nn. @ hock
In the horse, what does the medial plantar n. give off below the hock and where does it course?
communicating branch; courses over the SDF tendon
In the horse, which limb usually has the communicating branch from the medial plantar n. and what is the relative size?
thoracic limb; it is a lot larger than in the pelvic limb
In the horse, what does the medial plantar n. terminate as and where does this happen?
medial digital n. after passing the fetlock
In the horse, what does the lateral plantar n. branch into and where does this happen?
lateral and medial plantar MT nn.; branch at the proximal cannon bone
In the horse, what do the lateral and medial plantar MT nn. innervate and where do they run?
suspensory ligament; run deep to the suspensory ligament
In the horse, what does the lateral plantar n. terminate as and where does this happen?
lateral digital n. after passing the fetlock
In the rmt, where does the superficial peroneal n. run in relation to the horse?
Runs more distally
In the rmt, what does the superficial peroneal n. branch into?
dorsal common digital nn. II, III, IV
In the rmt, what does the dorsal common digital n. II terminate as?
dorsal proper digital nn. (axial II and abaxial III)
In the rmt, what does the dorsal common digital n. III terminate as?
dorsal proper digital nn. (axial III and axial IV)
In the rmt, what does the dorsal common digital n. IV terminate as?
dorsal proper digital nn. (abaxial IV, axial V)
In the rmt, what does the dorsal common digital n. III give off at the fetlock and what does it join?
Gives off communicating branch that joins dorsal MT n. III
In the rmt, which dorsal common digital n. is superficial?
IV
In the rmt, what is the distal course of the dorsal MT n. III?
Swings from dorsal to plantar aspect to join the plantar proper digital nn. (axial)
In the rmt, what does the deep peroneal n. become and where does this happen?
dorsal MT n. III @ proximal cannon bone
In the rmt, what is the peroneal n. deep to?
digital extensor tendons
In the rmt, what does the tibial n. divide into?
medial and lateral plantar nn.
In the rmt, what does the lateral plantar n. give off below the hock and what does it supply?
plantar MT n. –> interosseus m.
In the rmt, after the lateral plantar n. gives off the plantar MT n., what does it become?
plantar common digital n. IV
In the rmt, what does the plantar common digital n. IV terminate as?
plantar proper digital n. (abaxial IV)
In the rmt, what does the medial plantar n. divide into at the mid-distal cannon bone?
plantar common digital nn. II and III
In the rmt, what does the plantar common digital n. II terminate as?
plantar proper digital n. (abaxial III)
In the rmt, what does the plantar common digital n. III terminate as?
plantar proper digital n. (axial III and IV)
In the rmt, where should you block the distal limb on the dorsal side?
just below the hock
In the rmt, where should you block the distal limb on the plantar side?
proximal to the hock
What is the clinical significance of the ligament of the ergot in the horse and why is it important to know what this ligament is?
There is no clinical significance; important to know what it is bc it looks like a digital n.
In the horse, where do the dorsal branches of the digital nn. course and what do these branches supply?
Bt the dorsal digital v. and a.; supply to the skin
In the horse, if you want to target the digital n., where should you look?
On the plantar/palmar aspect
In the horse distal limb below the hock, what is the order from dorsal to plantar of the digital n., v., and a. that are located here?
Dorsal = digital vein Middle = digital artery Plantar = digital nerve
How is the thoracic limb oriented in comparison to the pelvic limb?
it is vertically-oriented whereas the pelvic limb is not
What % of body weight is carried by the thoracic limb?
60%
What are the functions of the thoracic limb?
Support trunk during gallop, shock absorption, and steering (thought to be)
What species have a tuber of the scapular spine and how are they sized relatively?
pig (largest), horse (intermediate), ruminant (barely there)
What species have an acromion process of the scapula?
dog and rmt
What species have a cartilaginous margin to their scapula and what are the relative sizes?
From smallest to largest = dog, pig, horse, rmt
What muscle inserts on the medial aspect of the scapula that has both thoracic and cervical parts? What is the function of this muscle?
serratus ventralis; thought to be important for shock absorption
What muscle originates at the supraglenoid tubercle of the scapula?
biceps brachii
What is the function of the cartilaginous margin of the scapula?
flexes for shock absorption
What species have both cranial and caudal parts to the greater tubercle of the humerus?
pig, ox, horse
What species have both cranial and caudal parts to the lesser tubercle of the humerus?
ox and horse
What species have an intertubercular/bicipital groove?
dog, pig, cat, ox
What species have an intertubecullar tubercle?
ox and horse
What courses through the intertubecular/bicipital groove?
Tendon of the biceps brachii m.
In what species do the radial fossa and olecranon fossa communicate and what feature of the humerus is unique to this species?
dog only; supratrochlear foramen
What feature do the antebrachial bones of the large animal possess that restricts them to only flexion and extension?
Radius and ulna hava some fusion with each other, so these animals are not able to supinate or pronate their antebrachium
What is a unique characteristic of the radius and ulna of the pig?
They are separate bones but are in close apposition bc they have a lot of c.t. bt them
How many spaces does the ox have bt its radius and ulna?
2 (proximal and distal interosseus spaces)
How many spaces does the horse have bt its radius and ulna?
1 (proximal interosseus space)
In the large animal, what feature of the distal antebrachium still appears as a secondary ossification center even though the bones are fused?
lateral styloid process
In the dog, what carpal bones are fused and what is this bone called?
radial and intermediate carpal bones –> intermedioradial carpal bone
In the pig, what carpal bones are fused?
None; they are all separate
In the ox, which carpal bones are fused?
2nd and 3rd carpal bones
In the ox, which carpal bones are absent?
1st carpal bone only
In the ox, if Mc 5 is present what does it look like?
It is a remnant
In the horse, which carpal bones are fused?
None; they are all separate
In the horse, which carpal bones are absent and with what frequency can they be present?
1st carpal bone (present 20-30% of the time)
5th carpal bone (present <20% of the time)
In the horse, what muscle makes up the cranial margin of the shoulder?
subclavius m.
What species have the subclavius m. and in which species is it largest?
pig and horse (large)
rmt (thin and strap-like)
What covers the infraspinatus muscle in the large animal?
Aponeurosis of the deltoideus m.
Which species only has the scapular part of the deltoideus m.?
horse
Which species does not have the accessory head of the triceps brachii m.?
horse
In the rmt, what heads of the triceps m. can be fused?
accessory and intermediate
What is the insertion of the supraspinatus m.?
greater and lesser tubercles of the humerus
How does the supraspinatus of the horse interact with the biceps brachii tenson?
tightly binds down the tendon
What is the origin of the long head of the triceps brachii m.?
caudal border of scapula
How does the insertion of the horse subclavius m. interact with the supraspinatus m.?
Part of the subclavius insertion is on the aponeurosis and fascia overlying the supraspinatus.
In the horse, what is the superficial part of the biceps brachii m. called and what does it join with?
lacertus fibrosus; joins fascia over the extensor carpi radialis m.
Do cattle have the lacertus fibrosus part of the biceps brachii?
Yes, but it is less developed than in the horse
Where does the deep part of the biceps brachii insert?
radial tuberosity
What species has a “true triceps” muscle?
Horse (only 3 heads)
What does the horse’s biceps muscle have that bisects it?
Thick band of c.t.
What innervates the muscles of the craniolateral antebrachium?
radial n.
What innervates the muscles of the caudomedial antebrachium?
median n. +/- ulnar n.
What is the origin and insertion of the extensor carpi radialis?
O: lateral epicondyle of the humerus
I: MC bones
What is the origin and insertion of the common digital extensor?
O: lateral epicondyle of the humerus
I: digits (P2 and P3)
What is the origin and insertion of the lateral digital extensor (thoracic limb)?
O: proximal radius and ulna
I: spp. specific
What is the origin and insertion of the extensor carpi radialis/ulnaris lateralis?
O: lateral epicondyle of the humerus
I: carpal and MC bones
What is the function of the extensor carpi ulnaris in the large animal and why?
It is a true flexor of the carpus due to larger component of insertion into the accessory carpal bone
How many bellies does the common digital extensor of the pig have?
3 (medial, middle, lateral)
How many bellies does the common digital extensor of the rmt have?
2 (medial and lateral)
How many heads does the common digital extensor of the horse have?
3
In the horse, what tendon comes off of the common digital extensor that joins the tendon of the lateral digital extensor at the hock?
tendon of Phillips from the radial head
