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pertaining to the upper limb.
brachial plexus a nerve plexus partly in the neck and partly in the axilla, originating from the ventral branches of the last four cervical spinal nerves and most of the ventral branch of the first thoracic spinal nerves. It has a supraclavicular part and an infraclavicular part that give off many of the principal nerves of the shoulder and upper limb.
plexus[plek´sus] (pl. plex´us, plexuses) (L.)
a network or tangle, chiefly of veins or nerves; see also rete. adj., adj plex´al.
plexus basila´ris a venous plexus of the dura mater located over the basilar part of the occipital bone and the posterior part of the body of the sphenoid bone, extending from the cavernous sinus to the foramen magnum.
brachial plexus see brachial plexus.
cardiac plexus the plexus around the base of the heart, chiefly in the epicardium, formed by cardiac branches from the vagus nerves and the sympathetic trunks and ganglia, and made up of sympathetic, parasympathetic, and visceral afferent fibers that innervate the heart.
carotid p's nerve plexuses surrounding the common, external, and internal carotid arteries.
celiac plexus solar plexus.
cervical plexus a nerve plexus formed by the ventral branches of the first four cervical spinal nerves and supplying the structures in the region of the neck. One important branch is the phrenic nerve, which supplies the diaphragm.
choroid plexus infoldings of blood vessels of the pia mater covered by a thin coat of ependymal cells that form tufted projections into the third, fourth, and lateral ventricles of the brain; they secrete the cerebrospinal fluid.
coccygeal plexus a nerve plexus formed by the ventral branches of the coccygeal and fifth sacral nerve and by a communication from the fourth sacral nerve, giving off the anococcygeal nerves.
cystic plexus a nerve plexus near the gallbladder.
dental plexus either of two plexuses (inferior and superior) of nerve fibers, one from the inferior alveolar nerve, situated around the roots of the lower teeth, and the other from the superior alveolar nerve, situated around the roots of the upper teeth.
lumbar plexus one formed by the ventral branches of the second to fifth lumbar nerves in the psoas major muscle (the branches of the first lumbar nerve often are included).
lumbosacral plexus the lumbar and sacral plexuses considered together, because of their continuous nature.
lymphatic plexus an interconnecting network of lymph vessels that provides drainage of lymph in a one-way flow. An example is the lymphocapillary vessels, collecting vessels, and trunks.
myenteric plexus a nerve plexus situated in the muscular layers of the intestines.
nerve plexus a plexus composed of intermingled nerve fibers.
1. in the male, a plexus of veins from the testis and the epididymis, constituting part of the spermatic cord.
2. in the female, a plexus of ovarian veins draining the ovary.
sacral plexus a plexus arising from the ventral branches of the last two lumbar and first four sacral spinal nerves.
solar plexus see solar plexus.
tympanic plexus a network of nerve fibers supplying the mucous lining of the tympanum, mastoid air cells, and pharyngotympanic tube.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
major nerve plexus formed of the ventral primary rami of the fifth cervical to first thoracic spinal nerves for innervation of the upper limb. The ventral primary rami entering into formation of the plexus constitute the roots of the plexus; the roots are located in the posterior triangle of the neck, converging to emerge from the scalenus anterior and medius muscles. As they emerge from the scalene hiatus, the C5 and C6 roots combine to form the superior trunk, C7 remains alone as the middle trunk, and the C8 and T1 roots combine to form the inferior trunk of the plexus. The trunks pass beneath the clavicle, passing from the neck into the axilla through the cervicoaxillary canal. As they cross the first rib, all three trunks divide into anterior and posterior divisions of the plexus. Nerve fibers contained within anterior divisions are destined for the anterior aspect of the limb; those contained within the posterior divisions are destined for the posterior aspect of the limb. Within the axilla, the anterior divisions of the superior and middle trunks merge to form the lateral cord of the plexus; the anterior division of the inferior trunk becomes the medial cord of the plexus, and the posterior divisions of all three trunks become the posterior cord, the cords being named for their position in relation to the axillary artery, to which they run parallel and which they surround. The cords of the brachial plexus give rise to most of the named peripheral nerves that are the products of the plexus formation. The major nerves of the lateral cord are the musculocutaneous nerve and the lateral root of the median nerve. The medial cord gives rise to the ulnar nerve and medial root of the median nerve. The lateral and medial roots of the median nerve merge to form the median nerve. The posterior cord of the plexus gives rise to the radial and axillary nerves.
Synonym(s): plexus brachialis [TA]
Farlex Partner Medical Dictionary © Farlex 2012
A network of nerves located in the neck and axilla, composed of the anterior branches of the lower four cervical and first two thoracic spinal nerves and supplying the chest, shoulder, and arm.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
brachial plexusA network of lower cervical and upper dorsal spinal nerves which supply the arm, forearm and hand. The brachial plexus begins in the posterior base of the neck and extends through the axilla, and is formed by the union of portions of C5 to C8 cervical and T1 spinal nerves.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
brach·i·al plex·us(brā'kē-ăl plek'sŭs)
A complex web of spinal nerves arising from the cervical spine; innervate the upper extremities.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
brachial plexusThe complicated rearrangement of spinal nerves arising from the spinal cord in the neck and in the upper back, which occupies the armpit (axilla), and supplies the many muscles of the arm.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005