Test 2 Info Flashcards
what are the general responsibilities of the cervical plexus?
motor to strap muscles
deeper neck muscles
phrenic n
skin of neck and chest
ANS: how many neurons are required to transmit a nerve impulse from the CNS?
2 (preganglionic and postganglionic)
PNS: how many neurons are required to transmit a nerve impulse from the CNS?
1
where do preganglionic cell bodies arise?
in CNS
where do postganglionic cell bodies arise?
outside CNS
are preganglionic fibers myelinated or unmyelinated?
myelinated
are postganglionic fibers myelinated or unmyelinated?
unmyelinated
what does the sympathetic nervous system innervate?
lungs (bronchodilation) heart (increase HR) BV walls (vasoconstriction- increase blood pressure) erector pilae sweat glands viscera dilator pupillae
also responsible for ejaculation
sympathetic NS: what are the relative lengths of the preganglionic and postganglionic fibers?
short preganglionic fiber, long postganglionic fiber
EXCEPT when passing thru and changing name to splanchnic
what does the parasympathetic NS innervate?
glands in head sphincter pupillae blood vessels heart lungs (bronchoconstriction) digestive tract bladder bowel "rest and digest"
parasympathetic NS: what are the relative lengths of the preganglionic and postganglionic fibers?
long preganglionic fiber and short postganglionic fiber
where do sympathetic cell bodies ORIGINATE?
intermediolateral grey portion of spinal cord (T1-L2)
what is the pathway through the sympathetic NS?
IMLG ventral root spinal nerve ventral rami white rami communicante sympathetic chain
is the white rami communicante preganglionic or postganglionic?
preganglionic
is the grey rami communicate preganglionic or postganglionic?
postganglionic
what are the 3 choices that could be made in the sympathetic NS?
- synapse AT THAT LEVEL in sympathetic chain ganglion and leave via grey rami
- synapse in NEARBY LEVEL in a sympathetic chain ganglion and leave via grey rami
- PASS THRU sympathetic chain (without synapsing) as splanchnic n. and synapse near target organ
is a splanchnic n preganglionic or postganglionic?
preganglionic
what is the ganglion impar and where is it?
where the paired ganglion unite, found at sacral level
sympathetic chains runs from __ to ___, and there are __ pairs of sympathetic ganglia
C1 to S4
22-23 pairs
what is the stellate ganglion?
where T1 ganglion blends with lower C ganglion – someone thought it looked like a star
greater splanchnic nn levels
T5-T9/10
lesser splanchnic nn levels
T10, T11
least splanchnic nn levels
T12
what do the lumbar splanchnic nerves arise from?
lumbar sympathetic ganglia (likely L1/L2)
** do not originate from the chain **
where do parasympathetic cell bodies originate?
cranio-sacral
CN 3, 7, 9, 10 + S2, S3, and S4
what parasympathetics does CN III control?
smooth muscle that constricts pupil and does lens accommodation
what parasympathetics does CN VII control?
secretion of tears and saliva
what parasympathetics does CN IX control?
secretion of saliva
what parasympathetics does CN X control?
heart
lungs (bronchi)
viscera (esophagus, smooth muscle and glands of trachea)
bowel, bladder
movements and glandular secretion of thoracic and proximal half of abdominal viscera
what parasympathetics does S2/S3/S4 control?
distal half of abdominal viscera (via PELVIC splanchnic n. – p for pelvic and parasympathetic)
bowel/ bladder (promote digestion)
erection (vasodilation)
what is acetylcholine (Ach) secreted by?
BOTH systems, preganglionic neurons (cholinergic)
almost all parasympathetic postganglionic fibers
what is noradrenaline secreted by?
almost all sympathetic postganglionic fibers
what controls ANS?
hypothalamus and solitary nucleus (receive afferent input) local reflexes (help with regulation of homeostasis)
what is the carotid sinus?
dilation of proximal part of internal carotid artery (right near bifurcation)
baroreceptor that reacts to changes in bp
what is the carotid sinus innervated by?
CN IX and X
if an increase in NP is sensed by the baroreceptors in the carotid sinus, what is the following process?
this afferent info (increase in BP) would be sent back to hypothalamus, where info would be integrated and then there is a response
ex: if you are exercising, this would be an appropriate response
if it is not an appropriate response, decrease sympathetic outflow and increase parasympathetic outflow
what is autonomic dysreflexia?
loss of supra spinal control (hypothalamus and solitary nucleus) of sympathetic NS and sacral segments (parasympathetic) of cord
uninhibited mass autonomic reflex response to noxious stimulus below level of injury
in what population is autonomic dysreflexia common?
pts with SCIs - especially cervical and high thoracic lesions (usually above T5/T6)
explain the vicious cycle of hypertension with autonomic dysreflexia
blood pressure elevates and the normal compensation method (decrease in sympathetics) cannot pass from higher centers thru level of lesion BUT message to slow the heart can travel through vagus n and cause bradycardia. way to solve dec HR is to inc BP, and cycle continues
s/s of autonomic dysreflexia
sympathetic below lesion and parasympathetic above lesion
pounding headache (bc of inc BP)
really high BP (>200/100)
slow pulse (<60bpm, symp)
flushing and sweating above lesion level (vasodilation)
pallor, goosebumps, cold clammy skin below level of lesion (vasoconstriction, symp)
nasal congestion (parasympathetic)
treatment for autonomic dysreflexia
alleviate noxious stimuli if possible
sit pt up to create orthostatic HTN
frequent bp checks
what medication should patients with frequent autonomic dysreflexia have, and what does it do?
atropine, decreases BP and increases HR
what medication should be used in emergent care for autonomic dysreflexia, and what does it do?
nitroglycerine, vasodilates
in what regions of the spinal cord is there a lordosis?
cervical and lumbar
in what regions of the spinal cord is there a kyphosis?
thoracic and sacral
how are cervical nerve roots named?
nerve root is ABOVE the vertebral it is named for (i.e., C1 nerve is above CV1)
how are nerve roots named at T1 and below?
nerve root exits BELOW vertebra it is named for (i.e., T1 nerve is below TV1)
what is the conus medullaris?
the termination of the spinal cord
what is the filum terminale internum?
tethered cord that prevents spinal cord from retracting or bouncing around
function of vertebral body
support
function of vertebral arch
protective (protects spinal cord)
made up of 2 pedicles and 2 laminas
function of vertebral foramen
houses spinal cord
function of intervertebral foramina
houses spinal nerves and vessels
pedicle
goes between transverse process and body
looks like tear drop on x ray film
lamina
goes between transverse process and spinous process
what structures form an intervertebral foramina?
inferior vertebral notch of vertebra above + superior vertebral notch of vertebra below
what structures form a facet joint?
inferior articulating process of vertebra above + superior articulating process of vertebra below
how many projections are there off the vertebral arch? (name them)
7 2 transverse processes 1 spinous process 2 SAP 2 IAP
distinguishing characteristics of cervical vertebrae
small, broad body (wider medial-lat than ant-post)
vertebral foramen is triangular
bifid spinous process
SAP faces posteriorly and up at 45 degrees
C1-C7 have transverse foramen
what do the transverse foramen house?
vertebral arteries
sympathetic nerves
venous plexus
what is an uncus (uncinate process) and where is it found?
found C3-C6 ONLY
prevents posterior translation of the vertebra
looks like little lip on lateral aspect of the body
at which levels does the vertebral artery travel?
CV1-CV6
cervical rotation: how is the movement split among vertebrae?
C1/C2 does 50% of rotational motion
C3-C7 does remaining 50%
characteristics of C1
no body - occupied by dens of C2
articulates with occiput
no true spinous process
has lateral masses
movements of C1
between occiput and atlas primarily glide/ chin tuck flex/ext 15 deg (small "yes" nod) sidebending 5 deg 0 deg rotation
characteristics of C2
called axis - think “axis of rotation”
distinguished by dens
small transverse processes
what holds the dens in place?
alar ligament and transverse ligament
movements btwn C1 and C2
40-45deg rotation (1/2 of cervical rotation)
0 deg sidebending
attachments of transverse ligament of atlas
C1 to C1
attachments of alar ligament
C2 to occiput
how might the dens fracture, and how would you figure it out?
flexion based accident or compression injury
open mouth x-ray
cervical myelopathy can occur due to…
pressure from herniated disc, bone spur, spinal stenosis, tumor, vertebral fracture
cervical myelopathy definition and its symptoms
compression of spinal cord s/s: neck pain numbness in both arms and hands muscle weakness in both legs balance disturbances incoordination of hands or feet
characteristics of thoracic vertebrae
- slightly larger in size
- have costal demifacets at junction of body and pedicles
- facets on transverses processes articulate with tubercle of ribs
- transverse and A-P dimension almost equal
- round vertebral foramen
- spinous process slants down and posterior (helps with protection)
- SAPs face posteriorly at 60 degree angle
what is a demifacet?
half a facet; found in thoracic vertebrae
orientation of SAPs throughout the spine
cervical: 45 degrees, posterior and up
thoracic: 60 degrees, posterior and up
lumbar: almost vertical (SAP faces medially and posteriorly)
what does a rib articulate with?
inferior costal facet of vertebra above
superior costal facet of vertebra below
transverse costal facet of vertebra below
rib is named for the level of…
superior costal facet and transverse costal facet
T11 and T12 are floating ribs - what does this mean?
they each only have 1 costal facet and therefore each rib only has 1 articulating surface (each articulates with its own respective rib)
the superior articular facet for the vertebral body (on rib) is going to articulating with the __ costal facet of the vertebra __
inferior costal facet of vertebra above
how many joints are there between ribs and thoracic spine (for ribs 3-9)?
3 joint surfaces, 2 joints (costovertebral joint and costotransverse joint)
thoracic vertebrae variations: T1
complete facet on superior aspect of body for whole head of rib 1
demifacet inferiorly to articulate with rib 2
thoracic vertebrae variations: T9
often no inferior demifacet for rib 10
thoracic vertebrae movements
flexion > rotation > extension/ side bending
what motion does the orientation of the facets in the thoracic region favor?
sidebending
this is restricted by ribs and organs
what type of joint is costovertebral joint
synovial joint
what ligaments are a part of the costovertebral joint?
radiate ligament
intra-articular ligament
what type of joint is costotransverse joint
synovial joint
what ligaments are a part of costotransverse ligament?
costotransverse ligament
superior costrotransverse ligament
lateral costotransverse ligament
characteristics of lumbar vertebrae
greatest body size no costal facets no transverse foramen body wider laterally than A-P spinous process almost horizontal to vertebral body
what motion is favored in lumbar spine, due to facet orientation?
flexion and extension
facets are oriented in sagittal plane
what is mamillary process?
located on superior articulating process in lumbar vertebrae
provides attachment for Multifidi
what is accessory process?
for muscle attachment in lumbar spine
ligaments of spine
anterior longitudinal ligament (ALL) posterior longitudinal ligament (PLL) ligamentum flavum interspinous ligament inter transverse ligament supraspinous ligament ligamentum nuchae
function and location of anterior longitudinal ligament (ALL)
unites vertebral bodies and IVDs - RESISTS TRUNK EXTENSION
located on anterior surface of vertebral body
attachments of ALL
occiput superiorly and sacrum inferiorly
function and location of posterior longitudinal ligament (PLL)
unites posterior aspect of vertebral bodies and IVDs - RESISTS TRUNK FLEXION
located INSIDE vertebral canal on POSTERIOR surface of vertebral bodies (ant surface canal)
** highly innervated with sensory nerve fibers
attachments of PLL
superior to axis (C2) and inferior to sacrum, primarily to IVD rather than bone
which is stronger - ALL or PLL?
ALL
ligamentum flavum location and function
connects lamina to lamina of vertebrae
function: resist separation of vertebral lamina and restrain mobility of facet joint
forms posterior wall of vertebral column
composed of YELLOW elastic tissue
thickest in lumbar region
interspinous ligament location and function
connects adjoining spines from root to apex
limits forward bending
very elastic, therefore weaker
intertransverse ligament location and function
between transverse processes
can limit SB and rotation
ligamentum nuchae function
continuation of supraspinous and interspinous ligaments in cervical region
gives rise to muscle attachment esp for C3-C5
supraspinous ligament function
connects tips of spinous processes of C7 to sacrum
limits forwarded bending
dentate ligaments - how many pairs?
20 pairs
function of dentate ligament
attaches dura mater to Pia mater
holds arachnoid layer of meninges and spinal cord suspended within dura
meninges superficial to deep
dura mater, arachnoid, pia mater
what is the “articular pillar” and in what region is it?
articular pillar is made up of collective articular processes of CERVICAL spine (just lateral to spinous processes)
IVDs are generally thicker anteriorly in the ___ regions
cervical and lumbar regions (lordotic regions)
how does IVD acquire nutrition?
via diffusion through spongy bone of adjacent vertebrae
what segments of the spinal cord do not have a disc between them?
C0/C1
C1/C2
none in sacrum or coccyx region
annulus fibrosis is…
inner layer of fibrocartilage and outer later of collagenous fibers, running in 12-18 concentric rings (run obliquely) along the outside of an IVD
function of annulus fibrosis
contains nucleus, permits deformation, resists tensile forces (has to be flexible enough to move when spine needs to move, but needs to resist stress as well)
which part of the IVD has mechanoreceptors and sensory receptors in it?
annulus fibrosis
relativeness thickness and size of annulus fibrosis in different areas of disc
larger and thicker anteriorly, smaller and thinner posteriorly
in which direction is a herniation most likely to occur?
posteriolaterally, bc annulus fibrosis is thinnest in that direction
protrusion of IVD
mildest form
annular fibers still remain intact, nucleus pulposus might start changing shape
prolapsed IVD
nuclear lateral reaches edge of disc and creates a bulge, annular fibrosis is still intact
extrusion of IVD
annular fibers rupture, some nuclear material escapes
nucleus pulposus is still intact
sequestration of IVD
nuclear lateral breaks and becomes pieces
most severe; health care professionals agree on this one most universally
what are facet joints innervated by?
branches of dorsal rami
during flexion, what aspect of disc is compressed?
anterior aspect
during flexion, what ligament becomes taunt?
PLL
during flexion, where does movement occur in the spinal column?
between inferior articulating process of vertebra above and superior articulating process of vertebra below
during extension, what aspect of disc is compressed?
posterior aspect
during extension, what ligament becomes taunt?
ALL
during side bending, what aspect of disc is compressed?
lateral aspect of disc
at the facet joint, sidebending is always coupled with what other motion?
rotation
in the cervical region, do SB and rotation occur to the same or opposite sides?
same side
in thoracic region, do SB and rotation occur to same or opposite sides?
opposite sides
in lumbar region, do SB and rotation occur to same or opposite sides?
opposite sides
during rotation, what aspect of disc is compressed?
shearing stress, not necessarily compressed in one region more than another
how many layers are there to thoracolumbar fascia?
3: posterior, middle, anterior
where does the posterior layer of thoracolumbar fascia attach?
lumbar and sacral spines and supraspinous ligaments
where does the middle layer of thoracolumbar fascia attach?
tips of lumbar transverse processes and ligaments, and to iliac crest and 12th rib
where is the anterior layer of thoracolumbar fascia?
covers QL
in thoracic region, what is the function of thoracolumbar fascia?
thin covering for vertebral extensors
in thoracic region, what are the attachments of thoracolumbar fascia?
medially to thoracic spine, laterally to costal angles
extensors and rotators of head and neck
splenius capitis and splenius crevices
short segmental muscles, deep back
interspinale and intertransversarii
spinal extensors
erector spinae: iliocostalis longissimus spinalis (ILS from lateral --> medial)
spinal rotators
(transversospinales)
semispinalis
rotators
multifidi
what is the common distal attachment of the erector spinae?
broad, thick tendon attached to median sacral crest
spines of T11, T12, and all lumbar vertebrae (+ their supraspinous ligaments)
medial, dorsal ileum
lateral aspect of sacral crest
iliocostalis muscles
iliocostalis cervicis
iliocostalis thoracis
iliocostalis lumborum
longissimus muscles
longissimus capitis
longissimus cervicis
longissimus thoracis
spinalis muscles
spinalis thoracis
spinalis cervicis
spinalis capitis
iliocostalis action
extension and lateral flexion of vertebral column
longissimus thoracis action
extend and side-bend vertebral column
longissimus cervicis action
extend and side-bend vertebral column
longissimus capitis action
extend head and rotate to same side
fiber direction of Multifidi
from inferolateral to superomedial
fiber direction of rotatores
inferolateral to superomedial
action of spinalis muscles
extension of vertebral column
muscles included in the transversospinalis muscle group
semispinalis thoracis semispinalis cervicis semispinalis capitis multifidi rotatores lumborum rotatores thoracis rotatores cervicis
action of semispinalis thoracis and cervicis
extend thoracic and cervical vertebral regions, rotate head contralaterally
action of semispinalis capitis
extends head, does minimal rotation
how long is each individual multifidus muscle?
3-4 vertebrae in length (attach to those above)
how long is each rotatores muscle?
3-4 vertebrae in length (attach to those above)
how long is each interspinales muscle?
about 1 vertebral level, between adjacent vertebral spines
how long is each intertransversarii muscle?
about 1 vertebral level, between transverse processes
actions of transversospinalis group
“endurance muscles”
postural, steadying, controlling vertebrae during motion
borders of suboccipital triangle
superomedial border: rectus capitis posterior major and minor
superior/ superolateral border: obliquus capitis superior oblique
inferior border: obliquus capitis inferior oblique
floor: AA membrane and posterior arch of C1
contents of suboccipital triangle
vertebral artery suboccipital nerve (dorsal ramus of C1)
what is epidural anesthesia?
regional anesthesia resulting from injection of an anesthetic into epidural space of spinal cord; goes thru dura mater
results in temporary anesthesia (but still motor control) of abdominal and genital region and lower extremities
where is an epidural anesthetic usually inserted and why?
either L3/4 space or L4/5 space
to protect spinal cord – spinal cord ends around L1/L2
is osteoporosis of the spine more prevalent in males or females?
females
what are the two types of osteoporosis of the spine that occur?
postmenopausal/ estrogen deficient osteoporosis
age related osteoporosis
typical osteoporosis fracture sites throughout body (in order)
vertebral bodies hip ribs radius femur
vertebral compression fracture s/s, and what x-ray will show
x-ray will show anterior wedge deformity severe back pain at site of fracture **may radiate** posture change (kyphosis) loss of height functional impairment disability decreased quality of life
what is spinal stenosis?
general term for narrowing of vertebral foramen, usually secondary to disc degeneration, osteophyte formation of vertebral bodies, or calcification of ligamentous material
this narrows the spinal canal
spinal stenosis can result in compression of…
neural tissue (spinal cord and nerve roots), resulting in sensory and motor dysfunction
spondylosis is…
typical joint change, facet joints and IVDs wear down, creating bone spurs leading to pain and stiffness
what is the pars interarticularis?
portion of the posterior arch between the superior and inferior articulating processes
spondylolosis is… and is caused by…
posterior arch defect
unilateral or bilateral stress fracture of the pars, most likely due to an acquired abnormality due to abnormal vertebral stress - NO SLIPPAGE
also could be seen in adolescents/ teens who do a lot of extension based activities in sports (ex: gymnast or diver)
how do you visualize a spondylolosis on an x-ray?
"Scottie dog" nose = transverse process eye = pedicle neck = pars - is there a fracture? ear = superior articulating process
how do you visualize a spondylolisthesis on an x-ray?
“Scottie dog”
neck = slippage of neck
spondylolisthesis is…
when one vertebral body slips forward in relation to an adjacent vertebrae
where is spondylolisthesis most common?
L4/L5 and L5/S1 interspace
what is spondylolisthesis usually due to?
overuse in young athletes, repetitive hyperextension
contents of anterior triangle
infrahyoid m thyroid and parathyroid glands common carotid a internal jugular v portions of last 3 CNs submandibular gland facial a internal carotid a internal jugular v CN IX CN X
transverse cervical nn ventral rami levels and what they come off of
come off cervical plexus
C1-C4 ventral rami
4 types of fascia in the neck
investing
pretrachial
carotid sheath
prevertebral
investing fascia surrounds…
most superficial
surrounds all neck structures and acts as roof to anterior triangle
pretrachial fascia surrounds…
thyroid gland
infrahyoid m
trachea
esophagus
carotid sheath surrounds…
internal jugular vein
carotid artery (common and internal)
vagus n
sometimes ansa cervicalis
prevertebral fascia surrounds…
all muscles of the neck besides SCM and trapezius
prevertebral muscles (longus colli, longus capitis)
scalene muscles
levator scap
phrenic n
deep muscles of back
forms floor of posterior triangle
contents of posterior triangle
transverse cervical a CN XI upper trunk of brachial plexus subclavian a dorsal scapular n long thoracic n n to subclavius supra scapular a supra scapular n
function of prevertebral muscles
longus colli, longus capitis
assist w neck flexion and are right next to vertebrae
4 infrahyoid muscles
sternohyoid
sternothyroid
thyrohyoid
omohyoid
function of infrahyoid muscles
depress hyoid bone and floor of mouth, elevate or depress larynx
important during talking and swallowing
4 suprahyoid muscles
digastric (anterior and posterior bellies)
geniohyoid
stylohyoid
mylohyoid
what cranial foramen does CN VII travel through, and which one does it exit out of?
travels through internal acoustic meatus and exits stylomastoid foramen
what travels through internal acoustic meatus?
CN VII (facial) CN VIII (vestibulocochlear)
what is Bell’s palsy?
irritation or inflammation of CNVII, lesions and affects muscles of facial expression on 1 side of face
where do cell bodies of CN VII originate?
pons and geniculate ganglion
