lumbar plexus


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Related to lumbar plexus: sciatic nerve, lumbar plexus block

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.

lumbar plexus

a network of nerves formed by the ventral anterior primary divisions of the first three and the greater part of the fourth lumbar nerves. It is located on the inside of the posterior abdominal wall, either dorsal to the psoas major or among its fibers and ventral to the transverse processes of the lumbar vertebrae. The branches of the lumbar plexus are the iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, obturator, accessory obturator, and femoral nerves. The iliohypogastric, ilioinguinal, and genitofemoral nerves supply the caudal part of the abdominal wall. The lateral femoral cutaneous, obturator, accessory obturator, and femoral nerves supply the anterior thigh and the middle of the leg. Only 20% of people have the accessory obturator nerve, which comes from the third and the fourth lumbar nerves. Compare sacral plexus. See also lumbosacral plexus.

lum·bar plex·us

(lŭm'bahr plek'sŭs)
1. A nervous plexus, formed by the ventral rami of the first four lumbar nerves; it lies in the substance of the psoas muscle.
2. A lymphatic plexus formed of about twenty lymph nodes and connecting vessels situated along the lower portion of the aorta and the common iliac vessels.

lumbar

pertaining to the loins.

lumbar epidural analgesia
see epidural anesthesia.
lumbar paralysis
paraplegia generally and specifically that due to cerebrospinal nematodiasis.
lumbar plexus
one formed by the ventral branches of the last four or five lumbar nerves in the psoas major muscle.
lumbar puncture
insertion of a needle and stylet into the subarachnoid space between the seventh lumbar vertebra and sacrum in most species except the dog, where the space between the sixth and seventh lumbar vertebrae is usually used; called also spinal puncture. A lumbar puncture may be done to measure the pressure of cerebrospinal fluid and obtain a specimen for examination, and to inject a contrast medium for special radiographic examinations such as myelography. As a therapeutic measure it is sometimes done to relieve intracranial pressure or to remove blood or pus from the subarachnoid space. A lumbar puncture also is necessary for injection of a spinal anesthetic.
lumbar spinal stenosis
see lumbosacral stenosis.
lumbar tap
see lumbar puncture (above).
lumbar vertebrae
the vertebrae between the thoracic vertebrae and the sacrum, numbering seven in dogs and cats, six in horses and cattle, and six or seven in sheep and pigs.

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.
References in periodicals archive ?
Lumbar plexus blocks, like all regional anaesthetic techniques, should ideally be performed on awake or lightly sedated patients, however many practitioners will safely undertake the block following general or spinal anaesthesia.
Both studies comparing continuous lumbar plexus block with continuous FNB for total hip arthroplasty found that patients ambulated earlier in the lumbar plexus group (23,24).
The technique is made possible by the anatomic fact that as the lumbar plexus descends between the quadratus lumborum and the psoas major muscles, it is invested by a fascial sheath of the two muscles.
Delayed retroperitoneal haematoma after failed lumbar plexus block.
We performed this posterior lumbar plexus block using a handheld ultrasound device (MicroMaxx Ultrasound System, Sonosite Inc.
Lumbar plexus block reduces pain and blood loss associated with total hip arthroplasty.
Postoperative analgesia and functional recovery after total-knee replacement: comparison of a continuous lumbar plexus (psoas compartment) block, a continuous femoral nerve block, and the combination of a continuous femoral and sciatic nerve block.
We hypothesised that this would allow the local anaesthetic to block the lumbar plexus at a higher level than the original fascia iliaca compartment block and hence block those nerves derived from the L1 and L2 anterior rami (ilioinguinal, iliohypogastric and genitofemoral).
25% for surgical anaesthesia and postoperative analgesia during lumbar plexus and sciatic nerve block in high-risk patients Vile performed combined lumbar plexus and sciatic nerve blockade on 62 consecutive A S4 111 or IV patients undergoing unilateral hip or femur surgery.
However, while it is true that Auroy et al "recorded only one case of cardiac arrest during a posterior lumbar plexus block, probably related to cephalad diffusion of the the local anaesthetic in the epidural space", Zanette et al do not mention that Auroy et al documented, in addition, two episodes of respiratory failure associated with the performance of a posterior lumbar plexus block, presumed due to cephalad spread via the epidural or intrathecal route'.