Anatomy of Upper Limb Blood Supply

Study Notes

Blood Supply to the Upper Limb

The arterial supply to the upper limb is delivered via five main vessels: subclavian artery, axillary artery, brachial artery, radial artery, and ulnar artery.

Subclavian Artery

The subclavian artery begins as the brachioccephalic trunk on the right and branches directly from the arch of aorta on the left.
It travels laterally towards the axilla and is divided into three parts based on its position relative to the anterior scalene muscle:
- First part: from origin to the medial border of the anterior scalene.
- Second part: posterior to the anterior scalene.
- Third part: from the lateral border of the anterior scalene to the lateral border of the first rib, where it enters the axilla and is renamed the axillary artery.

Scapular and Shoulder Anastomoses

Suprascapular artery: arises from the thyrocervical trunk and travels posterolaterally across the omohyoid muscle and then over the superior transverse scapular ligament.
Dorsal scapular arteries: connect with the suprascapular artery.
Acromial branches of thoraco-acromial artery: connect with acromial branches of the circumflex humeral and dorsal scapular arteries.
Posterior circumflex humeral artery and anterior circumflex humeral artery: anastomose around the shoulder joint.

Elbow Anastomoses

Radial collateral artery, middle collateral, recurrent interosseous, and posterior branch of the inferior ulnar collateral arteries: provide collateral circulation around the elbow joint.
Radial recurrent artery and radial collateral artery connect.
Inferior ulnar collateral artery, anterior ulnar collateral artery, posterior ulnar collateral artery, and superior ulnar collateral artery connect.

Wrist and Hand Anastomoses

The vasculature of the hand is characterized by multiple anastomoses between radial and ulnar vessels and palmar and dorsal vessels.
The arteries of the hand constitute a peri-articular arterial anastomosis around the collective joints of the wrist and hand.

Deep Veins

The deep venous system of the upper limb is situated underneath the deep fascia.
It is formed by paired veins that accompany and lie either side of an artery.
The brachial veins are the largest in size and are situated either side of the brachial artery.
Perforating veins run between the deep and superficial veins of the upper limb, connecting the two systems.

Clinical Relevance: Venepuncture

Venepuncture is the practice of obtaining intravenous access.
The median cubital vein is a common site of venepuncture due to its ease of access, fixed position, and superficial position.

Lymphatic Drainage of the Upper Limb

The lymphatic system functions to drain tissue fluid, plasma proteins, and other cellular debris back into the bloodstream and is involved in immune defense.
Lymph is filtered by lymph nodes and returns to the circulation via the venous system.

Description

This quiz covers the anatomy of the blood supply to the upper limb, including the five main arteries and their relationships. It also touches on anastomosis, palmar spaces, and movements of the forearm.