Learning Objectives

By the end of this article, you should be able to:

Identify the major arteries supplying the upper limb in proximal-to-distal order
Describe the anatomical course and key branches of each artery
Understand important arterial anastomoses of the upper limb
Apply anatomical knowledge to common clinical correlations

The arterial supply to the upper limb is provided by five main vessels, arranged from proximal to distal:

Subclavian artery
Axillary artery
Brachial artery
Radial artery
Ulnar artery

Together, these vessels ensure continuous perfusion from the thorax to the hand. This article reviews their anatomical course, major branches, and clinical relevance.

Subclavian Artery

The arterial supply to the upper limb begins with the subclavian artery.

On the right, it arises from the brachiocephalic trunk
On the left, it arises directly from the arch of the aorta

The subclavian artery passes laterally toward the axilla and is divided into three parts based on its relationship to the anterior scalene muscle:

First part: From its 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

At the lateral border of the first rib, the subclavian artery becomes the axillary artery.

Axilla: Axillary Artery

The axillary artery is a continuation of the subclavian artery and lies deep to the pectoralis minor, enclosed within the axillary sheath along with the cords of the brachial plexus.

It is divided into three parts, based on its position relative to the pectoralis minor:

First part: Proximal to pectoralis minor
Second part: Posterior to pectoralis minor
Third part: Distal to pectoralis minor

Major Branches

First part:
- Superior thoracic artery
Second part:
- Thoracoacromial artery
- Lateral thoracic artery
Third part:
- Subscapular artery
- Anterior circumflex humeral artery
- Posterior circumflex humeral artery

The circumflex humeral arteries form an anastomotic network around the surgical neck of the humerus, making them vulnerable to fractures at this site.

At the lower border of the teres major, the axillary artery becomes the brachial artery.

Clinical Relevance: Axillary Artery Aneurysm

An axillary artery aneurysm is an abnormal dilation of the artery to more than twice its normal diameter.

May compress the brachial plexus, causing paraesthesia and muscle weakness
Can compromise blood flow to the upper limb
Definitive treatment is surgical excision and vascular grafting

Upper Arm: Brachial Artery

The brachial artery is the main arterial supply to the arm and begins at the lower border of the teres major.

It gives off the profunda brachii artery, which accompanies the radial nerve in the radial groove and supplies the posterior compartment of the arm
The profunda brachii contributes to the elbow anastomosis

The brachial artery descends medially and enters the cubital fossa, where it lies beneath the bicipital aponeurosis. Here, it bifurcates into the radial and ulnar arteries.

Clinical Relevance: Brachial Artery Injury

Although the arm has good collateral circulation, complete occlusion or laceration of the brachial artery can result in:

Forearm muscle ischaemia
Muscle necrosis and fibrosis
Volkmann’s ischaemic contracture, causing a permanent flexion deformity of the hand

Forearm: Radial and Ulnar Arteries

The radial and ulnar arteries arise from the bifurcation of the brachial artery in the cubital fossa.

Radial Artery

Supplies the posterolateral forearm
Contributes to the elbow and carpal anastomoses
The radial pulse is palpable lateral to the tendon of the flexor carpi radialis

Ulnar Artery

Supplies the anteromedial forearm
Gives rise to the anterior and posterior interosseous arteries, supplying deep forearm structures
Contributes to the elbow anastomoses

Both arteries participate in arterial arches within the hand.

Hand: Superficial and Deep Palmar Arches

The hand has an extensive arterial network that allows continued perfusion even during high-resistance activities such as gripping.

Ulnar Artery

Enters the hand anterior to the flexor retinaculum
Continues as the superficial palmar arch
Gives rise to digital arteries supplying the fingers

Radial Artery

Enters the hand dorsally via the anatomical snuffbox
Passes between the heads of the adductor pollicis
Supplies the thumb and index finger
Continues as the deep palmar arch

Palmar Arches

Superficial palmar arch:
- Lies anterior to flexor tendons
- Supplies the digits
Deep palmar arch:
- Lies deep in the flexor tendons
- Supplies the wrist and contributes to digital blood flow