Week 3 - Blood Supply to the Upper Arm

Question 0

What happens to the subclavian arteries at the lateral border of the 1st rib?

Answer 0

They become the axillary arteries

Question 1

Where does arterial supply to the arm begin, and what are the origins of these vessels?

Answer 1

Starts with subclavian arteries.
Left is direct branch of aortic arch
Right is from brachiocephalic trunk

Question 2

At what level do the subclavian arteries become axillary?

Answer 2

The lateral border of the 1st rib

Question 3

What muscle does the axillary artery pass underneath in the axilla?

Answer 3

Pectoralis minor

Question 4

At what level do the anterior and posterior circumflex humeral arteries arise? Why is this clinically significant?

Answer 4

Surgical neck of the humerus - i.e. they may be damaged in a surgical humerus fracture

Question 5

What artery other than the circumflex humeral arteries also arises from the axillary artery at the surgical neck of the humerus?

Answer 5

Suprascapular artery

Question 6

What happens to the axillary artery at the level of teres major?

Answer 6

It becomes the brachial artery

Question 7

At what point does the axillary artery become the brachial artery?

Answer 7

Teres major

Question 8

What branches off the brachial artery immediately distally to teres major?

Answer 8

The profunda brachii artery

Question 9

What course does the profunda brachii take and how is this clinically relevant?

Answer 9

Descends on the posterior surface of the humerus, in the radial groove. In a mid-shaft humeral fracture there is therefore danger of damage to this artery.

Question 10

Which nerve does the brachial artery descend immediately posteriorly to?

Answer 10

The median nerve

Question 11

How does the brachial artery terminate, and where?

Answer 11

Bifurcates into the radial and ulnar arteries in the cubital fossa.

Question 12

The veins in the arm are either superficial or deep. How are the two systems connected?

Answer 12

Via perforating veins

Question 13

What are the two major superficial veins of the arm?
Where do they arise?
How are they connected, and where?

Answer 13

Basilic and cephalic
Dorsal venous network of hand
Via the median cubital vein, in the cubital fossa

Question 14

Describe the course of the basilic vein

Answer 14

Ascends on the medial side of the limb.

At teres major, it goes deeper and combines with the brachial veins to form the axillary vein

Question 15

Describe the course of the cephalic vein

Answer 15

Ascends on the lateral side of the limb
Sits between the deltoid and pectoralis major as it ascends
Joins the axillary vein

Question 16

Describe how the deep veins of the arm are arranged

Answer 16

Arranged as “venae commitantes” - i.e. pairs of veins either side of an artery. They are underneath the deep fascia.