lumbosacral plexus


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Related to lumbosacral plexus: brachial plexus, lumbosacral plexus injury

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.
pampiniform plexus
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.

lumbosacral plexus

Etymology: L, lumbus, loin, sacrum, sacred, plexus, braided
the combination of all the ventral anterior primary divisions of the lumbar, the sacral, and the coccygeal nerves. The lumbar and sacral plexuses supply the lower limb. The sacral nerves also supply the perineum through the pudendal plexus and the coccygeal area through the coccygeal plexus. See also lumbar plexus, sacral plexus.
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Lumbosacral plexus

lumbosacral plexus

The lumbar plexus and the sacral plexus.
See also: plexus

lumbosacral

pertaining to the lumbar and sacral region, or to the lumbar vertebrae and sacrum.

lumbosacral instability
see lumbosacral stenosis (below).
lumbosacral intumescence
the thicker portion of the spinal cord from which the roots of the lumbosacral plexus originate, corresponding to the caudal, cervical lumbar and the sacral spinal segments.
lumbosacral luxation
may result from trauma; common in dogs and cats. Neurological deficits result from injury to spinal nerves, and parenchymal hemorrhage and edema in spinal cord segments distant from the site.
lumbosacral plexus
a network made up of the caudal lumbar and sacral spinal nerves giving rise to the femoral, obturator, cranial gluteal, caudal gluteal, sciatic and pudendal nerves; innervates the perineum and muscles of the pelvic limb.
lumbosacral plexus injury
severe trauma to the hindlimbs may cause injury to the lumbosacral plexus, causing femoral and sciatic nerve deficits (inability to bear weight, extend or flex the stifle, dropped hock, and knuckling onto the digits).
lumbosacral spondylopathy
see lumbosacral stenosis (below).
lumbosacral stenosis
a reduction in diameter of the spinal canal at the level of the lumbosacral articulation may be caused by congenital anomalies of the vertebrae or acquired lesions. Weakness, pain and paresthesia with self-mutilation of the pelvic limbs and tail are clinical signs in dogs. Occurs as a congenital anomaly in some smaller dog breeds, and as an acquired defect in larger breeds, particularly the German shepherd dog.
lumbosacral syndrome
lesions involving the lumbosacral tumescence or the lumbosacral nerve roots. Signs include flaccid paresis or paralysis of pelvic limbs, paresthesia and sensory loss in the pelvic limbs, anal sphincter, tail, bladder and urethral sphincter, depressed or absent postural reactions in the pelvic limbs, and urine retention with passive incontinence. See also lumbosacral stenosis and lumbosacral plexus injury (above), cauda equina neuritis.

plexus

pl. plexus, plexuses [L.] a network or tangle, chiefly of veins or nerves.

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
a plexus of autonomic fibers and sympathetic nerve ganglia which surround the origin of the celiac artery, and supply the abdominal viscera.
celiacomesenteric plexus
a plexus of autonomic nerve fibers and sympathetic ganglia around the origin of the celiac and cranial mesenteric arteries; called also solar plexus.
cervical plexus
a network of nerve fibers formed by the first four cervical nerves and supplying the structures in the region of the neck.
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 last sacral nerves.
coronary plexus
a venous plexus within the coronet of the hoof.
cutaneous p's
superficial, middle and deep, inter-communicating plexuses of blood vessels are identified as supplying blood to haired skin.
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.
gonadal plexus
the collection of parasympathetic and sympathetic nerves to the gonads.
hoof plexus
plexus of veins draining the hoof region in the horse.
lumbar plexus
see lumbar plexus.
lumbosacral plexus
see lumbosacral plexus.
mesenteric plexus
parasympathetic and sympathetic nerve supply to the abdominal organs.
myenteric plexus
nerve plexus
a plexus composed of intermingled nerve fibers.
pampiniform plexus
1. a plexus of veins from the testis and the epididymis, constituting part of the spermatic cord.
2. a plexus of ovarian veins in the broad ligament of the uterus.
parametrial plexus
the venous plexus within the broad ligament providing venous drainage to the uterus and vagina.
plexus papilloma
see plexus papilloma.
pulmonary plexus
the array of autonomic nerves which supply the lungs.
renal plexus
autonomic nerve supply to the kidney.
sacral plexus
a plexus arising from the ventral branches of the last few lumbar and first few sacral spinal nerves.
solar plexus
see celiacomesenteric plexus (above).
tympanic plexus
a network of nerve fibers supplying the mucous lining of the tympanum and auditory tube.