Arterial Supply - Upper Limb

Question 1

Origin

Answer 1

Subclavian arteries
Left - from arch of aorta
Right - brachiocephalic trunk

Question 2

In the axilla

Answer 2

Once the subclavian arteries have crossed the lateral edge of the 1st rib they are called axillary arteries
Passes under pec. minor enclosed in axillary sheath
At humeral surgical neck the post. + ant. circumflex humeral arteries arise (supply shoulder region) / subscapular artery also arises here

Question 3

In the upper arm

Answer 3

Once the lower border of the teres major is reached it -> brachial artery
Gives rise to profunda brachii (deep artery of arm, travels along posterior humerus in radial groove, supplies posterior arm, terminates at elbow)
Brachial artery descends immediately posterior to median nerve
As it crosses cubital fossa -> bifurcates -> radial + ulnar arteries

Question 4

In the forearm

Answer 4

• Radial artery - supplies posterior aspect of forearm
• Ulnar artery - supplies anterior aspect of forearm
  Two arteries anastomose in hand by forming superficial and deep palmar arches

Question 5

In the hand

Answer 5

• Radial artery - mainly supply of thumb and lateral side of index finger
• Ulnar artery - mainly supplies rest of digits and medial side of index finger
• Common palmar digital arteries - arise from superficial palmar arch (supply digits)

Question 6

Axillary artery aneurysm

Answer 6

Aneurysm = dilation of a blood vessel to > twice its size
Can occur as result of atherosclerosis, thoracic outlet syndrome or trauma
Can compress brachial plexus producing neurological symptoms such as paresthesia and muscle weakness
Surgical treatment, removing aneurysm and reconstructing vessel wall using graft

Question 7

Occlusion or laceration of brachial artery

Answer 7

Arm has relatively good anastomotic supply which protects against partial or temporary occlusion of brachial artery
If artery totally occluded ischaemia in forearm can cause necrosis and paralysis of muscles of forearm
Affected muscles replaced to some degree by scar tissue and shorten considerably
Can cause flexion deformity - Volkmann’s ischaemic contracture