2.Deep/Intrinsic Back Muscles and Spine Part 1 Flashcards
define lordosis. which vertebrae would it be seen in?
Define kyphosis. which vertebrae would it be seen in?
Remember that curvature depends on anterior vs posterior view. so explain the vertebral curvatures
lordosis is a forward curve of the spine toward the midline- like a C.
-It would be seen with the Cervical and saCral vertebrae
kyphosis is hunchback like a backwards C. would be seen in thoracic and sacrococcygeal regions.
These definitions stay the same. BUT…
- cervical curve lordotic curve, convex anteriroly, concave posteriorly
- thoracic curve kyphotic curve; concave anteriorly, convex posteriorly
- lumbar curve lordotic curve; convex anteriorly, concave posteriorly
what causes the 3 abnormalities we see in spine curvature?
what is the most superior part of the spinal cord in an X-ray?
1) scoliosis- congenital or idiopathic
2) excessive kyphosis
- osteoporosis/ loss of bone density
3) excessive lordosis:
- prenancy
- congenital
dens of c2 is actually above c1 in the X-ray
which cervical vertebrae can you palpate?
typical vertebrae have a body+ __ processes, list them
which muscles attach to the ____ and ___ processes
c7 aka the vertebra prominens but there are exceptions
-it has a large spinous process
7 processes: 1 spinous process 2 transverse processes 2 superior articular processes 2 inferior articular processes
extrinsic and deep back muscles attach to the spinous and transverse process
what and where is the z joint; what type of joint
zygapophyseal j formed between the superior and inferior articular facets of vertebrae.
-paired synovial joints btwn facets on articular processes
describe the intervertebral disk jelly donut
-are you taller in space?
outside: donut aka the annulus fibrosus which as an outer wall of fibrocartilage
inside: inner nucleus pulpous which is more elastic, mass with high water content
yes taller in space bc no gravity to push on vertebral discs
what are the possible disc problems?
what can spinal stenosis be caused by?
1) degenerative disc disease: overuse especially with age
2) herniated nucleus pulposus
3) osteophytes aka bone spurs which occur when bone rubs against bone (secondary to degenerative disease)
spinal stenosis can be caused by hardening of the ligamentum flavum which connects lamina to lamina which impacts spinal nn and occurs with age
vertebral body compression fractures can be caused by ____? which is ____
what is the surgical approach
-what is the prevalence
osteoporosis which is loss of bone density; weak support
these are 2x more likely than hip fractures and usually affects 40% of 80 year old women but only 1/3 are diagnosed
surgical approach is called kyphoplasty (insert balloon into pedicle and liquid plastic)
what makes the vertebral canal
-where is the notch?
-where is the spinal cord?
where does this cord end and what happens after
what is the sacral hiatus? why important?
the vertebral canal is between what 2 ligamens?
vertebral canal is formed by stacked vertebral foramen and vertebral arches
notch is in PEDICLE
-spinal cord is in this canal * important concept but posterior to the vertebral bodies
cord ends at L1-L2V in the adult so it is shorter than the spine; after it ends, it continues as the sacral canal : continuation of vertebral canal in sacrum
-sacral hiatus is the end of the sacral canal; this is where S5 nerve and coccygeal spinal nerve are
spinal canal is between posterior longitudinal ligament and the ligamentum flavum
what is a herniated nucleus pulposus and what is it caused by?
which direction does it go? why?
what is the most common site of the HNP?
which movement is most likely to cause and HNP and why?
HNP is slipped or herniated disk;
can tear the annuli fibrosis
usually goes POSTLATERALLY-because it is stopped from going posteriorly by the (thin) posterior longitudinal ligament.
-most common site is lower lumbar, then lower cervical so specifically: L4-L5, L5-S1 (80%) bc of sacral promontory
and then C5-C6 (20-30%) and C6-C7 (60-75%) bc of extreme angle of lordosis
thoracic is very rare, but if it does it will by T11-T12 lower region as well
-flexion most likely to cause HNP because get anterior disk compression bc it closes the angle anteriorly and the disk can slip back
while a extension opens the angle and get posterior disk compression
explain the spinal nerve roots vs rami?
- each pair of sensory and motor ROOTS join in the intervertbral foramen to form a spinal nerve
-once outside the vertebral canal, the spinal nerve divides into posterior/dorsal/SENSORY and anterior/ventral/MOTOR RAMUS
each of which contains a mix of motor and sensory fibers
describe the naming system for spinal nerves in the crevical, lumbar, and thoracic areas
ex: name the nerve btwn
C2V - C3V
C5V-C6V
C7V-T1V
ex:
L2-L3V
L5-S1V
S1-S2V
the cervical spinal roots are from California (CA) therefore they are named for the vertebrae that THEY ARE ABOVE
exception: C8 is above T1 vertebrae
ex:
C2V - C3V: C3 nerve
C5V-C6V: C6 nerve
C7V-T1V: C8 nerve
for the remaining, they are from the south and are named for the vertebrae THAT THEY ARE SOUTH OF
ex:
L2-L3V: L2 nerve
L5-S1V: L5 nerve
S1-S2V: S1 nerve
what is radiculopathy?
causes?
symptoms?
any pathological problem affecting the spinal roots
causes:
HNP, osteophytes
symptoms: diminished dermatome sensation (if pinched long enough) or sharp burning stabbing pain down dermatome
- myotome: loss of muscle sensation
differences in symptom/clinical presentation of osteophyte versus herniated nucleus pulposus? **HIGH YIELD
osteophyte:
invades foramen
affects roots at that level
*no matter the spinal position
HNP:
-does not invade foramen
-affects roots at the level in cervical and thoracic (remember thoracic is from the south)
*EXCEPT WHEN IN LUMBAR REGION —> THEN IT SKIPS THAT LEVEL SPINAL ROOT AND GOES FOR THE ONE BELOW
why” as you go down the column, the disc moves under the vertebral foramen bc it gets so big
Practice questions:
Question 1: Osteophyte in the R. C3-C4 intervertebral foramen will affect roots from which spinal n? A-1st fig
Question 2: Osteophyte in the R. L3-L4 intervertebral foramen will affect roots from which spinal n? A-2nd fig
HNP between: C6-C7 C7V-T1V T2V-T3V L4V-L5V L5V-S1V osteophyte: L4V-L5V
1) C4n
2) L3n
In these examples: either C4n or L3n dermatomal pain followed eventually by dermatomal sensory loss; & C4n or L3n myotomal motor loss
HNP between: C6-C7: C7n C7V-T1V: C8n T2V-T3V: T1n L4V-L5V: L5n L5V-S1V: S1n (sciatica) osteophyte: L4V-L5V: L4n
a L5-S1 HNP is related to the sacral promontory how?
what is the sacral promontory?
what are the s/s of this HNP? what is this called clinically?
promontory is where the sacrum deviates from L5 and falls posteriorly into the sacrum
-L5 is the most weight-bearing vertebrae and where the promontory deviates is a hot spot for HNPs
–get pain in the S1 dermatome and irritates the S1 n root. called sciatica
thoracic HNP is very rare but what is affected?
Upper thoracic: HNP affects roots at same level
lower thoracic: HNP affects roots below (t11-t12 will affect T12n)
spondylosis vs spondylysis
spondylosis is osteoarthritis of the spine
each Zj is supplied by 2 medial articular branches, so how do you determine which it is that causes low back pain?
Zj has medial branch of 1 posterior rams called descending med articular br which is above Zj and one ascending medial articular br from the root at the level of the Zj
do a reversible nerve block to determine
what does scotty’s dog outline?
where is the Z j?
ear: superior artiuclar process
eye: pedicle
head/nose: transverse process
front leg: inferior articular process
Z joint is where the ear and the leg meet
how many layers for the superficial/extrinsic mm?
how many layers for the deep back mm? describe the layers
what is the nerve supply for all?
common bilateral function of almost all intrinsic back mm?
2: superficial and deep layers
deep back has 3 layers:
superficial, intermediate, deep
superficial:
- splenius m (deep to trapezius) in nuchal region
- like a bandaid
intermediate: erector spinae mm (3)
deep: transversopinal mm- semispinalis, multifidus, and rotator mm
nerve supply for all deep back mm is the posterior primary rami
common function: spine extension
function of the splenius m? made up of what 2 things? what is the orientation of these fibers
like a bandaid extends neck (posterior) in a bilateral action
also helps rotate neck in unilateral motion
-made up of splenius cervicis and capitas
orientation of fibers is superolateral
describe the 3 erector spinae muscles and their function
what is the orientation of these fibers
-deep to lats and serratus posterior inferiors:
most lateraL:
- iliocostalis (costal = rib) lumborum, thoracis, and cervicis
- think starting down lumbar, up to thoracic and then the neck - longissimus thoracis, cervicis, capitis
- think starting at thoracic, next is neck, and head - spinalis thoracis and cervicis
I love sex (ILS)
- together they extend spine posteriorly
- individually they bend spine laterally
describe the deep layer of the intrinsic muscles
this is the transversospinalis group:
-deep to the erector spine
1) semispinalis m (semi bc 1/2 as long as the spine)
which has htoracicis, cervicis, and capitis parts across 4-6 segments
2) multifidus m (deep to semispinalis) crosses 2-4 segments -unilaterally: rotates spine -bilaterally: extends spine -source of low back pain -important for spine stability to counteract degernartive pathology
3) rotator mm: functions like the multifidus; rotates trunk to opposite side
thoracolumbar fascia/ thoracodorsal is in the thoracic and lumbar regions to enclose intrinsic muscles of the back
in the lumbar region, how does this fascia sit?
in the thoracic region, how does it sit?
lumbar:
thick posterior layer from the spinous processes that lies posterior to the intrinsic muscles
middle layer from transverse processes lies anterior to intrinsic muscles
anterior layer from the transverse processes lies anterior to quadratus lumborum
layers laterally from transverses abdomens
thoracic:
from spinous processes to angles of ribs
how many spinal nerves in each region? how many in all?
spinal cord is continuos with ____ but ends as ___ where?
8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal 31 total
spinal cord is continuous with the medulla oblongata but ends at the conus medullaris is at level L1-L2
list and describe the levels of the meninges including the spaces
include how far they extend
epidural space: separates dura mater from periosteum. contains fat and internal vertebral venous plexus
- dura mater- outermost dense fibrous covering of cord. extends to S2. surrounds each nerve root into the intervertebral foramen
- subdural space: potential - arachnoid mater: membrane lining the dura and extending to S2 as well
- subarachnoid space : real - pia mater: adherent to the spinal cord
-has dentate ligaments which attach it to the dura
-filum terminale= extension of pia from conus
the interna of the film terminal is in the lumbar cistern
-the extern of the film terminal is connective tissue thread from S2 to coccyx
what is the lumbar cistern and the caudal equina?
lumbar cistern is the sac at end of conus medullar is
caudal equina: lower lumbar, sacral, and coccygeal dorsal and ventral roots descend here below the conus to exit to their respective interverebral foramina
what structures does the needle pass through in lumbar puncture?
skin subcutaneous fat supraspinous interspinous ligamentum flavum epidural space dura mater subdural space arachnoid mater
describe the blood supply to the cord
1) we have one anterior and 2 posterior SPINAL ARTERIES that come off the vertebral artery (remember the vertebral artery branches off the sublcavian
2) we also have SEGMENTAL ARTERIES bc the anterior and posterior spinal arteries are not enough blood. we have one for each region
Cervical: has ascending cervical, deep cervical, and vertebral
Thoracic: has posterior intercostal arteries
Lumbar: has lumbar arteries
Sacral: iliolumbar and lateral sacral
3) anterior and posterior MEDULLARY ARTERIES come down and supplement anterior and posterior spinal arteries that came off the vertebral artery
4) We also have SPINAL BRANCHES that come off the segmental arteries
a) from thoracic: anterior and posterior radicular arteries supply dorsal and ventral roots of spinal nerves
b) branches to vertebral bodies
describe the venous drainage of the cord
These are all valveless veins:
- arterial supply drains into the vertebral and vertebral venous plexuses
a) internal venous plexus is in the epidural space
b) external venous plexus is on the external surface of the vertebrae and enters back into systemic veins
