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"
Brachial plexus (CN XI) and an area of skin near the axilla innervated by the intercostobrachial nerve. The brachial plexus communicates through the sympathetic trunk via gray rami communicantes that join the plexus roots. The terminal branches of the brachial plexus (musculocutaneous n., axillary n., radial n., median n., and ulnar n.) all have specific sensory, motor and proprioceptive functions. Lesions can lead to severe functional impairment. Brachial plexus injury affects cutaneous sensations and movements in the upper limb. They can be caused by stretching, diseases, and wounds to the lateral cervical region (posterior triangle) of the neck or the axilla. Depending