Anatomy 2: Thoracic Limb

Front 1

what three intrinsic muscles of the thoracic limb are innervated by the axillary nerve?

Back 1

deltoideus
teres major
teres minor

Front 2

what six intrinsic muscles of the thoracic limb are innervated by the median nerve?

Back 2

flexor carpi radialis
pronator quadratus
pronator teres
superficial digital flexor
deep digital flexor, humeral head
deep digital flexor, radial head

Front 3

what three intrinsic muscles of the thoracic limb are innervated by the musculocutaneous nerve?

Back 3

biceps brachii
brachialis
coracobrachialis

Front 4

what ten intrinsic muscles of the thoracic limb are innervated by the radial nerve?

Back 4

abductor pollicis longus
anconeus
brachioradialis
common digital extensor
extensor carpi radialis
extensor carpi ulnaris
lateral digitial extensor
supinator
tensor fasciae antebrachii
triceps brachii

Front 5

what muscle of the thoracic limb is innervated by the subscapular nerve?

Back 5

subscapularis

Front 6

what two intrinsic muscles of the thoracic limb are innervated by the suprascapular nerve?

Back 6

infraspinatus
supraspinatus

Front 7

what three intrinsic muscles of the thoracic limb are innervated by the ulnar nerve?

Back 7

deep digital flexor, ulnar head
flexor carpi ulnaris, humeral head
flexor carpi ulnaris, ulnar head

Front 8

which five muscles originate, at least in part, on the lateral epicondyle of the humerus?

Back 8

common digital extensor
extensor carpi ulnaris
lateral digitial extensor
supinator
anconeus

Front 9

which five muscles originate, at least in part, on the medial epicondyle of the humerus?

Back 9

pronator teres
superficial digital flexor
deep digital flexor, humeral head
flexor carpi ulnaris, humeral head
flexor carpi radialis

Front 10

Which muscles originate or insert onto the olecranon?

Back 10

triceps brachii (all heads)
tensor fascia antebrachii
ulnar head of the flexor carpi ulnaris

Front 11

which five intrinsic muscles of the throacic limb can both flex the shoulder and extend the limb?

Back 11

deltoideus
anconeus
triceps brachii (all heads)
teres minor
teres major

Front 12

which muscles in the carnivores pronate the manus?

Back 12

pronator quadratus
pronator teres

Front 13

which muscles in the carnivores supinate the manus?

Back 13

supinator
brachioradialis

Front 14

which muscle, in the horse, is homolgous to the abductor pollicis longus in the dog?

Back 14

extensor carpi obliquus

Front 15

what does the cat have on its humeral condyle and why is it clinically important?

Back 15

a supracondylar foramen, through which passes the brachial artery and median nerve

Front 16

which ligaments help to hold the head of the humerus in its articulation with the glenoid cavity?

Back 16

- medial and lateral genohumeral ligaments
- transverse humeral retinaculum

Front 17

which ligaments keep the hinge joint of the elbow together?

Back 17

medial and lateral collateral ligaments

Front 18

in the dog, wraps transversely around the proximal articular circumference of the radius and attaches to the medial and lateral coronoid processes of the ulna

Back 18

annular ligament of the radius

Front 19

the deepest caudal/palmar ligament in the horse's manus that runs axially along the cannon bone

Back 19

suspensory ligament

Front 20

ligaments that help keep digits III and IV together in the ox

Back 20

proximal and distal interdigital ligaments

Front 21

ligament that connects the navicular bone to the coffin bone

Back 21

distal sesamoidean impar ligament

Front 22

what runs between the deep digital flexor tendons and the navicular bone in the horse?

Back 22

navicular bursa

Front 23

what ligaments help to reinforce and anchor the attachments of muscles to the proximal sesamoid bones in the horse?

Back 23

- intersesamoidean ligament
- palmar annular ligament

Front 24

what wraps around the carpal bones like and ace bandage? What are its two parts called?

Back 24

annular ligamant of the carpus
- flexor retinaculum
- extensor retinaculum

Front 25

what nerve runs under the acromion? In the horse, since it lacks an acromion, what is the name of the condition in which this nerve is damaged?

Back 25

- suprascapular nerve
- damaged is called sweeney

Front 26

name the proximal carpal bones in the dog from medial to lateral

Back 26

1. intermedioradial carpal bone
2. ulnar carpal bone
3. accessory carpal bone

Front 27

how many distal carpal bones exist in the dog, horse, ox, and pig?

Back 27

dog: 4
horse: 3 or 4 (C1 is missing 50% of the time)
ox: 2 (C2+C3 and C4)
pig: 4

Front 28

to what part of the distal phalanx does the claw attach?

Back 28

ungual process

Front 29

which spinal nerves comprise the brachial plexus?

Back 29

ventral branches of C6-T2

Front 30

In the horse, what are the common names for the Carpus, MC2 and MC4, MC3, P1, P2, P3, the MP joint, the P1-P2 joint, and the P2-P3 Joint?

Back 30

Carpus = knee
MC2 and MC4 = splint bones
MC3 = cannon bone
P1 = long pastern bone
P2 = short pastern bone
P3 = coffin bone
MP Joint = Fetlock Joint
P1-P2 Joint = Pastern Joint
P2-P3 Joint = Coffin Joint

Front 31

which ventral spinal nerves comprise the subscapular nerve?

Back 31

C6, C7

Front 32

which ventral spinal nerves comprise the suprascapular nerve?

Back 32

C6, C7

Front 33

which ventral spinal nerves comprise the musculocutaneous nerve?

Back 33

C7, C8, (C6)

Front 34

which ventral spinal nerves comprise the radial nerve?

Back 34

C7, C8, T1, (C6), (T2)

Front 35

which ventral spinal nerve comprises the axillary nerve?

Back 35

C8

Front 36

which ventral spinal nerves comprise the median nerve?

Back 36

C8, T1

Front 37

which ventral spinal nerves comprise the ulnar nerve?

Back 37

C8, T1, T2

Front 38

Name the seven intrinsic nerves of the thoracic limb in order from their origins in the brachial plexus from cranial to thoracic

Back 38

subscapular - C6, C7
suprascapular - C6, C7
musculocutaneous - C7, C8, (C6)
radial - C7, C8, T1, (C6), (T2)
axillary - C8
median - C8, T1
ulnar - C8, T1, T2

Front 39

which nerve supplies shoulder muscles whose major function is to flex the shoulder?

Back 39

axillary nerve

Front 40

which nerve supplies shoulder muscles whose major function is to extend the shoulder?

Back 40

suprascauplar nerve

Front 41

which nerves supply shoulder muscles whose function is to adduct and extend the shoulder?

Back 41

subscapular nerve, musculocutaneous nerve

Front 42

which nerve supplies caudal arm muscles whose major function is to extend the elbow joint?

Back 42

radial nerve

Front 43

which nerve supplies cranial arm muscles whose major function is to flex the elbow joint?

Back 43

musculocutaneous nerve

Front 44

which nerve supplies craniolateral forearm muscles whose major function is to extend the manus?

Back 44

radial nerve

Front 45

which nerves supply caudomedial forearm muscles whose major function is to flex the manus?

Back 45

median nerve, ulnar nerve

Front 46

what are the four ossification centers of the scapula?

Back 46

1. body and neck
2. cranial part of the glenoid cavity
3. supraglenoid tuberosity
4. coracoid process

Front 47

what the the three PRIMARY ossification centers of the humerus?

Back 47

- proximal epiphysis
- diaphysis
- distal epiphysis

Front 48

what the the four SECONDARY ossification centers of the humerus?

Back 48

1. greater tubercle
2. deltoid tuberosity
3. medial epicondyle
4. lateral epicondyle

Front 49

what passes over the convexity of the greater tuberosity of the humerus?

Back 49

the tendon of the infraspinatous muscle

Front 50

what are the three ossification centers of the radius?

Back 50

- proximal epiphysis
- diaphysis
- distal epiphysis

Front 51

what are the three ossification centers of the ulna?

Back 51

- shaft and part of the olecranon
- summit of the olecranon
- distal epiphysis

Front 52

In the horse, what is the order, in size from largest to smallest, of the carpal bones?

Back 52

C3 > radial > intermediate > ulnar ~ C4 > C2

Front 53

name the three distal sesamoidean ligaments of the horse and their attachments

Back 53

- superficial distal sesamoidean ligament: proximal sesamoid bones --> palmar aspect of P2. Called the "I" ligament

- middle distal sesamoidean ligament: base of the proximal sesamoid bones --> ridges on the surface of P1. Called the "V" ligament

- deep distal sesamoidean ligament: passes from the base of each sesamoid with its two parts crossing --> palmar aspect of P1. Called the cruciate or "X" ligament

Front 54

name the main artery of the thoracic limb from the axilla to the phalanges and the points at where it changes names

Back 54

Subclavian -->
axillary (at the 1st rib) -->
brachial (when it crosses the latissimus dorsi attachment) -->
median (past the common interosseus artery; just past elbow joint) -->
superficial & deep palmar arches and superficial and deep dorsal branches (after it crosses the manus)

Front 55

what are the four major branches of the axillary artery?

Back 55

1. superficial cervical
2. external thoracic
3. lateral thoracic
4.subscapular (branches to thoracodorsal, caudal circumflex humeral)

Front 56

what are the six major branches of the brachial artery?

Back 56

1. cranial circumflex humeral
2. deep brachial
3. collateral ulnar
4. bicipital
5. transverse cubital
6. common interosseous (ulnar, cranial & caudal

Front 57

what are the three major branches of the median artery?

Back 57

1. deep antebrachial
2. radial
3. superficial palmar arch

Front 58

what connects the cephalic vein to the median vein?

Back 58

median cubital vein

Front 59

from what two venous structures does the cephalic vein originate?

Back 59

- palmar venous arches
- accessory cephalic vein

Front 60

what two superficial thoracic limb veins empty into the external jugular vein?

Back 60

- cephalic vein
- omobrachial vein

Front 61

which superficial thoracic limb vein empties into the axillary vein?

Back 61

axillobrachial vein

Front 62

what extra structure of the biceps brachii of the horse assists with the passive stay apparatus and where does it attach?

Back 62

the lacertus fibrosis (fibrous lizard); attaches on the tendon of the extensor carpi radialis; pulls up on the cannon bone and carpal joint

Front 63

which two muscles in the horse have check ligaments?

Back 63

superficial digital flexor - proximal check ligament
deep digital flexor - distal check ligament

Front 64

what are the points of attachment for the suspensory ligament in the horse?

Back 64

runs from the sesamoid bones to the accessory carpal bone, and forms extensor branches that cross medially and laterally to combine with the tendon of the common digital extensor muscle

Front 65

what are the two main branches of the equine median nerve?

Back 65

medial palmar
lateral palmar

Front 66

what are the two main branches of the equine medial palmar nerve?

Back 66

medial palmar digital
medial dorsal digital

Front 67

what are the four major branches of the equine lateral palmar nerve?

Back 67

medial metacarpal
lateral metacarpal
lateral palmar digital
lateral dorsal digital

Front 68

what are the names of the four major equine manus nerve blocks from distal to proximal?

Back 68

1. palmar digital (heel) block
2. proximal sesamoidal (high digital) block
3. distal metacarpal (palmar) block
4. proximal metacarpal (high 4-point) block

Front 69

In the dog, what four major arteries supply the manus?

Back 69

1. median a. - palmarly
2. caudal interosseus a. - dorsal and palmar
3. superficial antebrachial a. - dorsally
4. radial a. - dorsal and palmar

Front 70

in the dog, what path does the superficial antebrachial artery take to supply the dorsal manus?

Back 70

superficial antebrachial a. -->
dorsal common digital a. -->
axial and abaxial dorsal proper digital aa.

Front 71

in the dog, what path does the caudal interosseus artery take to supply the dorsal manus?

Back 71

caudal interosseus a. -->
dorsal rete -->
dorsal metacarpal aa. -->
axial and abaxial dorsal proper digital aa.

Front 72

in the dog, what path does the radial artery take to supply the dorsal manus?

Back 72

radial a. -->
dorsal rete -->
dorsal metacarpal aa. -->
axial and abaxial dorsal proper digital aa.

Front 73

in the dog, what paths does the caudal interosseus artery take to supply the palmar manus?

Back 73

first path:
caudal interosseus a. -->
superficial palmar arch -->
palmar common digital aa. -->
axial and abaxial palmar proper digital aa.

second path:
caudal interosseus a. -->
deep palmar arch -->
palmar metacarpal aa. -->
axial and abaxial palmar proper digital aa.

Front 74

in the dog, what path does the median artery take to supply the palmar manus?

Back 74

median a. -->
superficial palmar arch -->
palmar common digital aa -->
axial and abaxial palmar proper digital aa.

Front 75

in the dog, what path does the caudal interosseus artery take to supply the palmar manus?

Back 75

caudal interosseus a. -->
deep palmar arch -->
palmar metacarpal aa. -->
axial and abaxial palmar proper digital aa.

Front 76

in the horse, what is the name of the anastamosis of the medial and lateral palmar digital arteries?

Back 76

terminal arch

Front 77

the proximal boundary of the horse hoof where it borders the hairy skin

Back 77

coronary border

Front 78

the portions of the hoof visible in the standing horse

Back 78

hoof wall (toe, quarters, heels)

Front 79

the weight-bearing portion of the hoof that contacts the ground

Back 79

sole border of the hoof wall

Front 80

the bottom of the hoof that does not bear weight in a healthy animal

Back 80

sole of the foot

Front 81

a relatively soft, triangular structure on the solar surface of the foot of the horse

Back 81

frog

Front 82

the mushy pad of fibrous tissue between the frog, deep digital flexor tendons, and hoof cartilages

Back 82

digital cushion

Front 83

the dermis of the hoof

Back 83

corium

Front 84

the outer skin of the proximal hoof wall

Back 84

periople

Front 85

the proximal most dermis of the hoof

Back 85

perioplic corium

Front 86

the thick dermal tissue distal to the perioplic corium

Back 86

coronary corium

Front 87

the long, vertically-ridged dermis of the hoof

Back 87

laminar corium ("sensitive laminae")

Front 88

the most distal part of the laminar corium

Back 88

terminal papillae

Front 89

the dermal tissue that follows deep to the sole border of the hoof wall

Back 89

sole corium

Front 90

the dermal tissue that nourishes the frog of the hoof

Back 90

frog corium

Front 91

what are the three epidermal layers of the hoof wall?

Back 91

1. stratum externum - periople
2. stratum medium - thickest part of the hoof wall that contains the pigment
3. stratum internum (= epiderminal laminae; horny laminae; insensitive laminae) - deepest surface, has "mushroom gills" that intercalate with the laminar corium and bear weight.

Front 92

what features of the stratum medium of the hoof act as shock absorbers?

Back 92

tubular and intertubular horn

Front 93

what parts exist in both the laminar corium and the stratum internum that allow them to stick together?

Back 93

primary and secondary laminae

Front 94

if a dog fractures the humerus and you are to repair it from the lateral side, which muscles would you retract to access the bone? Which structures should you be careful not to damage

Back 94

- go between the brachialis and the lateral head of the triceps.
- don't damage the musculocutaneous and radial nn. or the cephalic vein

Front 95

what is commonly broken in the elbow of the dog? Accessing it laterally, what muscle must be retracted and what structure should not be damaged?

Back 95

- the anconeal process of the ulna is often fractured
- the anconeus muscle must be retracted
- don't damage the ulnar nerve

Front 96

in a fracture of the antebrachium, going in from the medial side, what muscle must be retracted and what structure should not be damaged?

Back 96

- flexor carpi radialis
- don't damage the median nerve

Front 97

mineralization of hoof cartilage

Back 97

sidebones

Front 98

an infected and draining hoof associated with the hoof cartilages

Back 98

quittor

Front 99

What nerves are blocked in a palmar digital nerve block in the horse? What are their landmarks? What does it desensitize?

Back 99

- The medial and lateral palmar digital nerves.
- near their veins and arteries of the same name at the level of the mid-pastern. Think "VAN" - vein-artery-nerve from inside-out.
- desensitizes all the structures in the hoof except the dorsal part of the coronary band

Front 100

What nerves are blocked in a proximal sesamoidal nerve block in the horse forelimb? What are their landmarks? What does it desensitize?

Back 100

- blocks the medial and lateral palmar nerves at the level of the sesamoid bones
- block about an inch above the proximal sesamoid bones
- lateral palmar nerve is lateral to the superficiel and deep digital flexor tendons
- medial palmar nerve is medial to the superficial digital flexor tendon and runs palmar to the medial palmar artery
- desensitizes the entire digit below the block except for the dorsal pastern

Front 101

What nerves are blocked in a distal metacarpal nerve block in the horse? What are their landmarks? What does it desensitize?

Back 101

- blocks the medial and lateral palmar metacarpal nerves and the medial and lateral palmar nerves
- both sets of nerves are blocked just distal to the buttons of the splint bones, and between the flexor tendons and the suspensory ligament
- this block densitizes the digit below the splint bones, including the fetlock joint

Front 102

What nerves are blocked in a proximal metacarpal nerve block in the horse? What are their landmarks? What does it desensitize?

Back 102

- the medial and lateral palmar nerves are blocked at the level of the carpus.
- block the nerves distal to the accessory carpal bone, which lie either medial or lateral to the digital flexor tendons
- this desensitizes the entire digit and most structures in the caudal metacarpus.

Front 103

What nerves are blocked in an abaxial sesamoid nerve block in the horse? What are their landmarks? What does it desensitize?

Back 103

- the medial and lateral palmar nerves are blocked at the level of the sesamoid bones
- block the nerves medial and lateral as they run over the sesamoid bones
- desensitizes the entire digit below the block except for the dorsal pastern. Problems with the proximal aspects of the proximal sesamoid bones will still show.

Front 104

To do surgery on the bovine manus with a 4-point nerve block procedure, what nerves are blocked and where?

Back 104

a few inches above the second and fifth digits:

- dorsal branch of the ulnar nerve: dorsal to the flexor tendons; groove between the cannon bone and the interosseus muscle.
- palmar branch of the ulnar nerve: between the flexor tendons and the interosseus muscle

mid-metacarpal region:
- superficial branch of the radial nerve: on the dorsomedial side medial to the common digital extensor tendon
- median nerve: on the palmolateral side between the interosseus muscle and the flexor tendons

Front 105

To do surgery on the bovine manus with a general intervenous nerve block with a tourniquet, where is the tourniquet placed and where is anesthetic injected?

Back 105

- tourniquet is placed in the mid-metacarpal region
- anesthetic is injected into the dorsal common digital vein

Front 106

In the horse, which nerve supplies the dermatome of the caudomedial manus and antebrachium?

Back 106

median palmar nerve

Front 107

In the horse, which nerves supply the dermatome of the craniomedial manus and antebrachium?

Back 107

medial antebrachial and medial carpometacarpal cutaneous nerves

Front 108

In the horse, which nerve supplies the dermatome of the caudolateral manus and antebrachium?

Back 108

lateral palmar nerve

Front 109

In the horse, which nerve supplies the dermatome of the craniolateral manus and antebrachium?

Back 109

dorsolateral carpometacarpal cutaneous nerve
(yes, I know it's a long name)