Anatomy LE 1: Upper Limb Blood Supply and Venous and Lymphatic Drainage

Arterial Supply of the Upper Limb

• The aorta is the first blood vessel on the left side of the heart, which branches into three parts: brachiocephalic trunk, left common carotid, and left subclavian artery
• The brachiocephalic trunk separates into right common carotid and right subclavian artery
• The subclavian artery ascends laterally, exiting the thoracic inlet, and crosses posteriorly to the anterior scalene muscles, giving off several branches for the head, neck, and scapular regions

Axillary Artery

• The axillary artery begins at the lateral border of the 1st rib as a continuation of the subclavian artery
• It continues as the brachial artery at the inferior border of the teres major muscle
• The axillary artery is enclosed within an axillary sheath and is crossed anteriorly by the pectoralis minor muscle, dividing it into three parts
• It supplies blood to the shoulder and scapula

Branches of the Axillary Artery

• Anteriorly, it supplies the pectoralis major muscle
• Laterally, it supplies the cords of the brachial plexus
• One branch: Superior (Highest) thoracic artery, which supplies the first and second intercostal spaces and the superior part of the serratus anterior

Brachial Artery

• The brachial artery is a continuation of the axillary artery at the lower border of the teres major muscle
• It gives off a deep branch and a collateral branch, supplying the arterial anastomosis of the elbow before dividing into radial and ulnar arteries
• It terminates opposite the neck of the radius by dividing into the radial and ulnar arteries

Radial and Ulnar Arteries

• The radial artery begins in the cubital fossa at the level of the neck of the radius and descends downward and laterally
• It leaves the forearm by winding around the lateral aspect of the wrist to reach the dorsum of the hand
• The ulnar artery is the larger of the two terminal branches of the brachial artery and lies anterior to the ulnar head
• It descends through the anterior compartment of the forearm and ends by forming the superficial palmar arch, anastomosing with the superficial palmar branch of the radial artery

Venous Drainage

• Superficial veins are placed immediately beneath the skin, in the superficial fascia
• Deep veins accompany arteries and are typically named similarly to the artery they are in close proximity to
• The superficial palmar arch is more distal than the deep palmar arch
• The proper palmar digital arteries of the superficial palmar arch supply blood to the small, ring, middle, and medial side of the index finger (3 and ½ digits)
• The radialis indicis supplies blood to the lateral side of the index finger, while the princeps pollicis artery supplies blood to the thumb (1 and ½ digits)

Dorsal Venous Arch (Network)

• Composed of dorsal digital veins that drain into dorsal metacarpal veins
• Lies on the dorsum of the hand, in the subcutaneous tissue proximal to the metacarpophalangeal joints
• Venous drainage begins with the dorsal venous arch receiving blood from the digits and drains into the cephalic vein laterally (radial side), and basilic vein medially (ulnar side)