Arcuate Arteries (Shoulder)

The intraosseous part of axillary artery has been called the arcuate artery due to its posteromedial path after going into the humeral head. Multiple sections radiate in order to supply the subchondral bone of the humeral head. Arcuate arteries are ending sections of axillary artery. The axillary artery is the extension of the subclavian artery. This artery is generally separated into three portions. The first portion is over the superior border of the pectoralis minor, the second portion is deep towards the pectoralis minor, and the third portion is distal to the lateral border of the pectoralis minor. The usual number of branches for all of the three sections resembles the name of the section. The first section has one branch, the second has two, and the third has three.

The humeral head can totally profuse right after ligation of the anterior humeral circumflex artery on its entry spot within the humeral head. Large metaphyseal arteries which travelled through the fused growth plate in order to anastomose along with the arcuate artery within six of the eight normal and control specimens. In addition, significant intraosseous anastomoses occurred between the arcuate artery and the posterior humeral circumflex artery through the posteromedial vessels described in the foregoing and the vessels of the greater and lesser tuberosities.

Clinical Significance

The last division is referred to as the arcuate artery. Even though the main arterial blood supply towards the humeral head is through this ending division, there are significant intraosseous anastomoses among the arcuate artery along with posterior medial vessel divisions via the posterior humeral circumflex. Some perfusion of the humeral head continues if the head portion in a fracture expands distally under the articular surface. This has been verified clinically within a new proximal humerus fracture category scheme.