thoracic limb - vessels & nerves

Question 1

“____ coalesce and pass through _____ _____ before flowing into ____.”

Answer 1

“VESSELS coalesce and pass through LYMPH NODES before flowing Into VEINS.”

Question 2

What region of the body do larger arteries lie in?

Answer 2

Deeper/more medially (to protect from injury)

Question 3

What directions do arteries and veins flow?

Answer 3

Arteries: carry O2-rich blood from the heart to organs and extremities

Veins: carry O2-poor blood from organs and extremities to the heart

Question 4

What is collateral and recurrent circulation?

Answer 4

If a vessel becomes occluded, blood will still be able to flow to that region of the body because of the following alternative routes:
- collateral aa. (branches off main artery)
- recurrent aa. (go opposite in direction of blood flow and anastomose with the collateral aa.)

Question 5

What do vessel names reflect?

Answer 5

The area of the limb or the structure supplied

Question 6

Identify each superficial v. of the thoracic limb.

Answer 6

Orange: cephalic
Green: median cubital
Brown: brachial
Yellow: cephalic
Blue: cephalic
Pink: accessory cephalic
Cyan: dorsal common digital v. #4

Question 7

Identify each superficial v. of the thoracic limb.

Answer 7

Red: omobrachial
Orange: cephalic
Yellow: cephalic
Green: median cubital
Blue: cephalic
Pink: accessory cephalic
Gray: cephalic

Question 8

What is the sequence for the main artery to the manus?

Answer 8

Subclavian a. –> axillary a. –> brachial a. –> median a.

Question 9

Distal to the mid-antebrachium, how does the main arterial flow differ in dogs vs. cats?

Answer 9

Dogs: median a. –> main source of arterial flow
Cats: radial a. –> main source of arterial flow

Question 10

What is the name of the artery that runs deeply between the radius and ulna that is a major arterial contributor to the manus in both dogs and cats?

Answer 10

The caudal interosseous artery

Question 11

What is the superficial palmar arch artery?

Answer 11

Is the primary blood supply to the digits; lies on the palmar side in between tendons of the superficial and deep digital flexors

Question 12

What is the deep palmar arch artery?

Answer 12

Is the secondary blood supply to the digits; lies on the dorsal side in between tendons of the deep digital flexor and interosseous mm.

Question 13

Each blood vessel in the metacarpus runs from what regions?

Answer 13

From a CMC jt. to a MCP jt.

Question 14

Each blood vessel in the metacarpus is positioned how?

Answer 14

In a position relative to (“between”) two MC bones.

Question 15

What is the brachial plexus composed of?

Answer 15

The first 2 thoracic nerves and the last 3 cervical nerves, all which innervate motor and sensory neurons of the thoracic limbs.

Question 16

Interpret:

Radial nerve (C6-T2)

Answer 16

The radial nerve is composed of cervical spinal nerves 6, 7 & 8, and thoracic spinal nerves 1 & 2

Question 17

What are the major nerves contributing to motor function?

Answer 17

radial and ulnar nerves

Question 18

What are the major nerves contributing to sensory function?

Answer 18

radial, median and ulnar nerves

Question 19

What is the motor function of the radial nerve?

Answer 19

innervation of the extensor muscles of the forelimb, which is imperative for bearing weight

Question 20

What is the function of the ulnar nerve?

Answer 20

joins the median nerve in innervating muscles that flex the carpus & digits.

Question 21

What do the sensory nerves supply to?

Answer 21

the muscles and periosteum (fibrous sheath that covers bones/contains the blood vessels and nerves that provide nourishment and sensation to the bone)

Question 22

What has occurred to a cat who has lost function to one of its forelimbs?

Answer 22

paralysis of the radial nerve

Question 23

What are the differences between dermatomes/cutaneous zones and autonomous zones?

Answer 23

Dermatomes/cutaneous zones: areas of skin innervated by a spinal nerve (e.g., cervical or thoracic) or by a single, specifically named nerve (e.g., radial nerve). Overlapping of zones occurs.

Autonomous zones: areas of skin innervated purely by a single spinal nerve. No overlapping of zones occurs.