Axillary artery – Easy Anatomy 3D (2024)

The arteries of the upper limb supply the bones and soft tissues of the pectoral girdle, the lateral part of the thoracic wall, as well as all organs and tissues of the free part of the upper limb with blood.

In this video, we will consider the anatomy of the axillary artery (arteria axillaris) and its branches, as well as its areas of blood supply.

The axillary artery (arteria axillaris) arises at the level of the external border of the first rib, passes down the medial side of the pectoral joint and humerus next to the vein of the same name, and is surrounded by the trunks of the brachial plexus.

At the level of the inferior border of the pectoralis major muscle, it passes into the brachial artery (a. brachialis).

According to the topography of the anterior wall of the axillary cavity, the axillary artery is conditionally divided into three sections:

1. The sternoclavicular triangular

2. Pectoral triangle

3. Subpectoral triangle

In the first section, located at the level of the clavipectoral triangle, the following branches arise from the axillary artery:

• Subscapular branches (rami subscapulares), which supply the muscle of the same name with blood, these branches are irregular;

  

• The superior thoracic artery (arteria thoracica superior) arises proximal to the external border of the scalenus anterior muscle.

  

  It gives branches going to the first and second intercostal spaces, supplying their muscles with blood, and gives branches to the pectoral muscles.

  In the second section, located at the level of the pectoral triangle, 2 arteries arise:

• The thoraco-acromial artery (arteria thoracoacromialis) arises from the trunk of the axillary artery above the superior border.

  

  

  It penetrates the clavipectoral fascia with its branches, supplying blood to the upper limb and torso areas.

  This artery gives off 4 branches, let’s consider them in greater details.

  • The clavicular branch (ramus clavicularis) passes in the superior medial direction to the sternoclavicular joint, where it supplies the joint and subclavian muscle with blood.

    

  • The pectoral branch (ramus pectoralis) goes inferiorly and medially to the pectoral muscles, where it supplies the muscles and mammary glands with blood.

    

    

  • The acromial branch (ramus acromialis) crosses the coracoid process medially and pierces the deltoid muscle, supplying it with blood.

    

    Then it reaches the acromion, where it enters the acromial anastomosis system.

  • The deltoid branch (ramus deltoideus) goes over the tendon of the pectoralis minor muscle, then through the deltopectoral groove.

  

  

  Along its length, it supplies the pectoralis major and deltoid muscles with blood.

• Lateral thoracic artery (arteria thoracica lateralis) passes almost vertically down along the lateral border of the pectoralis minor muscle.

  

  

  It is usually covered by a large pectoralis major muscle. The artery ends in the fifth intercostal space. It often anastomoses with branches of the internal thoracic artery, especially in women.

  In the third section, located at the level of the subpectoral triangle, 3 arteries arise:

• The subcapular artery (arteria subscapularis) is the firs ranch of the third segment of the axillary artery.

  

  

  It arises after the lateral thoracic artery at the level of the inferior border of the subscapularis muscle. It passes inferiorly and laterally along the posterior wall of axillary cavity, following the lateral edge of the subscapularis muscle.

  It supplies the deltoid muscle, the latissimus dorsi muscle, the long head of the triceps brachii muscle, as well as the subscapularis, supraspinatus, infraspinatus and serratus anterior muscles.

  The subscapular artery is divided into 2 terminal branches:

  • The thoracodorsal artery (arteria thoracodorsalis) passes along the lateral edge of the scapula and supplies the teres major muscle, anterior dentate muscle, and latissimus dorsi muscle

    

    

  • The circumflex scapular artery (arteria circumflexa scapulae) passes through a three-sided opening to the infraspinatus muscle and other muscles adjacent to the artery, supplying them and the skin of the scapular area with blood

  

• The anterior circumflex humeral (arteria circumflexa anterior humeri) is smaller than the posterior one, follows in front of the surgical neck of the arm to the shoulder joint and deltoid muscle, supplying them with blood.

  

• The posterior circumflex humeral artery (arteria circumflexa posterior humeri) passes through a four-sided opening together with the axillary nerve.

The branches of this artery anastomose with the branches of the anterior circumflex humeral artery and supply the shoulder joint and the muscles located around it with blood.