W3 vasculature of upper extremity

Question 1

• Route of main artery

Answer 1

o Originates from subclavian artery in the root of the neck
o Subclavian continues posterior to clavicle and enters axilla where it becomes axillary artery
o Subclavian gives off branch called thyrocervical trunk which is important in collateral circulation in shoulder
o Axillary gives off 5 branches and then becomes brachial artery in arm
o Brachial artery gives rise to deep branch for posterior compartment
o Anterior to elbow, brachial splits into radial and ulnar arteries
o Anastomose with each other at the hand to become superficial and deep palmar arches

Question 2

• Five branches of axillary

Answer 2

o	Superior thoracic
o	Thoracoacromial 
o	Lateral thoracic
o	Subscapular
o	Anterior humeral circumflex
o	Posterior humeral circumflex

Question 3

• Collateral branches

Answer 3

o Present in shoulder, elbow and wrist joints
o Present to bypass blockages in main arteries and still get blood into the hand
o Also allow for planned ligation of main artery at specific locations that would not result in serious consequences for the limb

Question 4

• Collateral circulation around the shoulder

Answer 4

o Blockages at the axillary artery proximal to the subscapular artery may be bypassed by anastomoses between the branches of thyrocervical trunk and subscapular artery

Question 5

• Collateral circulation around the elbow

Answer 5

o Blockages of brachial artery distal to origin of the superior and inferior ulnar collaterals may be bypassed by anastomoses between recurrent branches of the radial and ulnar arteries and brachial and deep brachial arteries

Question 6

• Collateral circulation around the wrist

Answer 6

o Blockages of either the radial or ulnar artery in the distal forearm may be bypassed by the anastomoses established between these two arteries through the superficial and deep palmar arches