<Tr> <Th> FMA </Th> <Td> 5906 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terms of neuroanatomy (edit on Wikidata) </Td> </Tr> <P> The brachial plexus is a network of nerves formed by the anterior 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 . </P> <P> 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" branches, such as the subscapular nerve, the thoracodorsal nerve, and the long thoracic nerve, that leave the plexus at various points along its length . A common structure used to identify part of the brachial plexus in cadaver dissections is the M or W shape made by the musculocutaneous nerve, lateral cord, median nerve, medial cord, and ulnar nerve . </P>

Where do all nerves in the arm root from