Brachial ArteryEdit
The brachial artery is the principal blood vessel supplying the upper arm. It is the continuation of the axillary artery from the lower border of the teres major and runs down the arm to furnish the forearm and hand with arterial blood. Along its path, it gives off several important branches that serve both the arm and elbow region, and it ends by dividing into the radial and ulnar arteries near the elbow. Clinically, its pulse is commonly used to assess circulatory status in the upper limb, and it serves as a preferred site for arterial access in certain procedures.
Its position and branches reflect a straightforward design: a sturdy conduit that supports dynamic movement of the arm while maintaining reliable perfusion of the limb. The brachial artery lies medial to the biceps brachii tendon and passes along the arm with accompanying veins and nerves, most notably the profunda brachii artery (deep brachial artery) which is accompanied by the radial nerve in the posterior aspect of the arm. The deep brachial artery supplies the posterior compartment of the arm and contributes to collateral circulation around the elbow through its connections with the collateral arteries. The artery's distal portion gives off several elbow-related branches, including the superior ulnar collateral artery and the inferior ulnar collateral artery, which participate in an anastomotic network around the elbow joint.
Anatomy
Origin and course
The brachial artery begins as a continuation of the axillary artery at the inferior border of the teres major. It descends in the arm with a medial relation to the biceps brachii and lies adjacent to the median nerve and the accompanying veins. It is intimately related to the muscular and neurovascular structures of the arm, providing a reliable conduit for blood flow to the forearm and hand.
Branches
The deep or profunda brachial artery arises from the brachial artery in the upper arm and travels with the radial nerve in the spiral groove, delivering blood to the triceps and posterior arm muscles. In the distal arm and around the elbow, the brachial artery gives off the superior ulnar collateral artery and the inferior ulnar collateral artery, which contribute to the vascular supply of the elbow and its surrounding structures. These collaterals form an anastomotic network that maintains perfusion if primary flow is compromised.
End and distribution
Near the elbow, the brachial artery bifurcates into the radial artery and the ulnar artery, typically just distal to the elbow joint near the neck of the radius. The radial and ulnar arteries then run in the forearm to supply the muscular compartments and the hand, with additional branches forming the palmar arches and supplying the digits. The brachial artery also gives off small nutrient branches to the humerus and surrounding tissues as it travels.
Relations
In the arm, the brachial artery is closely associated with the musculature of the upper arm and with the nerves that pass through the region, including the median nerve and the musculocutaneous nerve proximally. The distal relationship near the elbow places it near the cubital fossa, where practical clinical access for arterial puncture and sampling is common. The artery’s course and divisions are important considerations in surgical planning and in the interpretation of vascular imaging.
Clinical significance
Pulse and assessment
The brachial pulse is palpated medial to the biceps tendon in the antecubital fossa and is a standard site for assessing arterial blood flow. It is often used for non-invasive blood pressure measurement, especially in adults and older children, and serves as a gateway for certain diagnostic and therapeutic procedures.
Arterial access and procedures
Because of its stability and accessibility, the brachial artery is used for arterial cannulation in some critical-care settings and for arterial blood gas sampling when radial access is not feasible. Knowledge of its trajectory and branching is critical to minimize complications such as hematoma, pseudoaneurysm, or nerve injury.
Injury, disease, and variations
Trauma to the upper arm can involve the brachial artery, potentially compromising perfusion to the distal limb. Peripheral vascular disease can affect the arterial supply of the upper limb, including the brachial segment, though disease more commonly involves the more distal arteries of the arm and hand. Anatomical variations in the branching patterns of the brachial artery exist and can influence surgical approaches, imaging interpretation, and the planning of vascular procedures. In reconstructive or orthopedic contexts, awareness of the brachial artery and its collaterals is essential to preserve limb viability.