Axillary Block

The course of the axillary artery is palpated and marked in the proximal axilla.

The expected location of the median nerve is superficial and lateral to the artery with the radial nerve posterior to the artery and the ulnar nerve medial to the artery.

A. Image of the left axilla demonstrating surface anatomy relevant to the axillary block: axillary artery and coracobrachialis muscle. B. Illustration of the cross-sectional anatomy through the axillary artery in the proximal axilla demonstrating the expected distribution of the terminal branch nerves in this location. PM, pectoralis major; MC, musculocutaneous; BC, biceps; CB, coracobrachialis; M, median; V, axillary vein; A, axillary vein; U, ulnar; DBA, deep brachial artery; R, radial; H, humerus. Reproduced from Bigeleisen P, Orebaugh S. Ultrasound guided axillary block. In: Chelly JE. Peripheral nerve blocks: a color atlas. 3rd Edition. Philadelphia: Lippincott Williams & Wilkins, 2009: 286, with permission.