Movement lecture 4: Vasculature of the upper limb

Question 1

What is the first branch of the subclavian artery?

Answer 1

Vertebral

Question 2

What is the second branch of the subclavian artery?

Answer 2

Internal thoracic

Question 3

What is the third branch of the subclavian artery?

Answer 3

Thyrocervical trunk

Question 4

What is subclavian steal syndrome?

Answer 4

Occlusion of the subclavian artery proximal to the vertebral artery origin causing reversed flow in the ipsilateral vertebral artery. Blood is stolen from the circular vertebrobasilar system (Circle of Willis) to supply the distal territory of the occluded or stenosed artery. Radial pulse much weaker on affected side.

Question 5

Where does the subclavian artery become the axillary artery?

Answer 5

Lateral border of the first rib. Divided into thirds by pectoralis minor muscle.

1. First part superior to muscle
2. Second part deep to muscle
3. Third part inferior to muscle

Question 6

Where does the axillary artery become the brachial artery?

Answer 6

Inferior border of teres major.

Question 7

What are the three main branches coming off the brachial artery before its bifurcation?

Answer 7

• Profunda brachii
• Superior ulnar collateral artery
• Inferior ulnar collateral artery

Question 8

Where is the bifurcation of the brachial artery into radial and ulna?

Answer 8

Cubital fossa

Question 9

What are the features of the profunda brachii artery?

Answer 9

• Deep artery of the arm
• Supplies the posterior compartment of the arm
• Wraps around posterior surface of humerus
• Runs in radial groove with radial nerve.

Question 10

What does the degree of ischaemia after brachial injury depend on?

Answer 10

Degree of ischaemia after brachial artery injuries depends on whetherinjury is proximal or distal to profunda brachii

Ligation of the brachial artery proximal to the profunda brachii artery will result in a loss of limb in about 50% of cases whereas amputation occurs in 25% of cases with ligation distal to profunda brachii

Question 11

What are the peri-articular anastamoses?

Answer 11

Network of anastomoses of brachial and profunda brachii arteries in the arm with radial and ulnar arteries in the forearm.

Ensures blood flow to the forearm even if elbow is fully flexed.

Question 12

What is supplied by the radial artery?

Answer 12

Supplies the anterolateral aspect of the forearm including flexors and extensors

Question 13

What is supplied by the ulnar artery?

Answer 13

Runs through forearm with the ulnar nerve
Supplies the medial side of forearm – mainly flexors and pronators
Gives off common interosseous artery (trunk) near its origin.
This divides into anterior and posterior interosseous arteries which supply the middle of the flexor and extensor compartments respectively.

Question 14

What happens when the radial artery enters the hand?

Answer 14

Passes dorsally and crosses the floor of the anatomical snuff box.
Pierces 1st dorsal interosseous muscle and passes between the transverse and oblique heads of adductor pollicis to enter the palmer surface of the hand.

Question 15

How does the ulnar artery enter the hand?

Answer 15

Enters the hand through the ulnar canal (Guyon’s canal) superficial to the flexor retinaculum.

Question 16

How do the ulnar and radial arteries anastamose within the hand.

Answer 16

Superficial and deep palmer arches (not present in all of the population).

Question 17

How many pulse points can you find in the upper limb?

Answer 17

Six:

• Axillary
• Brachial x 2 (mid arm and cubital fossa)
• Radial x 2 (wrist and anatomical snuffbox)
• Ulnar

Question 18

Where does the superfical venous drainage come from?

Answer 18

Begins with dorsal venous arch which receives blood from digits.

Question 19

Where does the cephalic vein drain from?

Answer 19

Drains lateral side of dorsal venous arch.

Question 20

Where does the basilic vein drain from?

Answer 20

Medial side of dorsal venous arch.

Question 21

Where is the median cubital vein?

Answer 21

Median cubital vein lies superficial to bicipital aponeurosis (ie roof of cubital fossa): useful site for venepuncture

Question 22

What are the venae comitantes?

Answer 22

Two veins (sometimes more) that closely accompany an artery in such a manner that the pulsations of the artery aid venous return.

Vena comitantes accompany all of the major arteries of the upper limb.

Question 23

What are the features of the venae comitantes of the upper limb?

Answer 23

Venae comitantes drain blood from the superficial and deep palmer arches to the vessels accompanying the radial and ulnar arteries

These continue to the cubital fossa, where they unite to form venae comitantes of the brachial vein

These venae comitantes merge with the basilic vein in the axilla to form the axillary vein.

Question 24

What are the features of the axillary vein?

Answer 24

Formed by union of basilic vein and brachial venae comitantes
Receives blood from the cephalic vein
Renamed subclavian vein after it passes under clavicle

Question 25

What are features of the subclavian vein?

Answer 25

Joins internal jugular vein to form brachiocephalic veins

The two brachiocephalic veins join to form the superior vena cava