Brachial plexus Brachial plexus The brachial plexus is a network of nerves formed by the ventral rami of the lower four cervical nerves and first thoracic nerve (C5, C6, C7, C8, and T1). This plexus extends from the spinal cord, through the cervicoaxillary canal in the neck, over the first rib, and into the armpit. It supplies afferent and efferent nerve fibers to the chest, shoulder, arm and hand. The brachial plexus is divided into five "roots", three "trunks", six "divisions" (three anterior and three posterior), three "cords", and five "branches". There are five "terminal" branches and numerous other "pre-terminal" or "collateral"
Axillary artery axillary vein, which lies medial to the artery, along its length. In the axilla, the axillary artery is surrounded by the brachial plexus. The second part of the axillary artery is the reference for the locational descriptions of the cords in the brachial plexus. For example, the posterior cord of the brachial plexus is so named because it lies posterior to the second part of the artery. The axillary artery has several smaller branches. The branches can be remembered, in order, when traveling from the heart, with the mnemonics "Screw The Lawyers Save A Patient", "Summertime: The Lakers Schedule Another