Spinal Lecture 3 Flashcards
what shape are the superior and inferior surfaces of the vertebral body?
kidney shaped and quite flat
lateral to the anterior longitudinal ligament is the attachments of the ___ of the diaphragm (upper _ lumbar on right, upper _ lumbar on left)
attachments of the CRURA of the diaphragm (upper 3 lumbar on the right, upper 2 lumbar on left)
what is an apophysis
a rim of smoother, less pitter, raised surface which is the second ossification centre of the vertebral body
what is found on the posterior surface of the vertebral body to transmit the nutrient arteries?
nutrient foramen
what attaches/projects from the lateral edges of the posterior surface of the vertebral body, more superior then inferior?
pedicles
what is the function of the pedicles?
transmit tension and bending forces
are pedicles short or long?
short
do pedicles overlap one another?
No except in the T-spine
what projects from each pedicle toward midline?
lamina
lamina fuse together forming the roof of the ___
neural arch
what is the function of the lamina?
disperse forces applied to the SAPs and IAPs
describe the superior edges of the lamina
irregular and sharp
describe the lateral edge of the lamina
rounded and smooth
where is the inferior articular process (IAP) found?
at the inferolateral corner of the lamina
where is the superior articular process of the lamina found?
superior (and with the pedicle)
describe the lamina
broad, triangular
do the lamina overlap?
yes but not as much as the thoracic
what defines the vertebral foramen?
the lamina
describe the superior and inferior surfaces of the superior articular process (facet)
concave (superior and convex (inferior) surfaces
which direction does the superior articular process (facet) face in the L-spine?
faces posteromedially - important for function
which direction does the inferior articular process (facet) face in the L-spine?
faces anterolaterally
what is the function of the zygoapophyseal joint?
resists forward sliding and twisting
what is another name for fat pads in the lumbar spine?
fibroadipose tissue or meniscoids
what forms the vertebral foramen?
nerual arch and the back of the vertebral body
what shape is the vertebral foramen?
traingular
Compare the size of the vertebral foramen in the L-spine to the C-spine and T-Spine.
Larger then in the thoracic spine and smaller than in the cervical spine
Explain why the L-spine vertebral foramen are larger than the thoracic foramen and smaller than cervical foramen.
Size is based on neural distrubution and increased need for mobility (needs more room for spinal cord to move).
because conventional surgies are often done in the prone position how are the anterior and posterior walls of the vertebral foramen described?
identified as the floor (anterior) and roof (posterior)
below what level does the vertebral foramen house the cauda equina (tail of the spinal cord)
below L2
the spinous process projects ___ from the junction of the __
the spinous process projects POSTERIORLY from the junction of the LAMINA
describe the shape of the spinous process
quadrangular, narrow blade of bone
is the spinous process on a similar or different plane than its body?
same plane as its body
List a few muscles / ligaments that attach to the SP’s
erector spinae,
spinalis thoracis,
multifidi,
interspinal muscles and ligaments
supraspinous ligaments
what extends laterally from the junction of the lamina and pedicle?
TP
describe the shape of the TP
flat and rectangular, thin and long
TP’s of L1-L3 increase OR decrease in length?
increase
describe distinguishing characteristics of the TP of L5
shorter, faces superolateral, continuous with the whole of the pedicle, encroaches on body
the transverse process has an ___ which marks the inferior aspect of the root of each transverse process, on the __ surface near attachment to the ___
ACCESSORY PROCESS which marks the inferior aspect of the root of each transverse process, on the POSTERIOR surface near the attachment to the PEDICLE
lumbrosacral IVD is ___ shaped with an ___ in height ___
WEDGE shaped with an INCREASE in height ANTERIORLY
the shape of L5 vertebrae is ___ shaped, higher ___
wedge shaped, higher anteriorly
what are intervertebral foramen also known as?
radicular canals; which are not true canals as there are no boundaries
each intervertebral foramen is a curved channel running around the ____ medially, containing ___
each intervertebral foramen is a curved channel running around the PEDICLE medially, containing NERVE ROOTS
describe the shape of the intervertebral foramen
oval upper end and traiangular lower end
what forms the anterior wall of the intervertebral foramen?
IVD
what forms the posterior wall of the intervertebral foramen?
superior articular facet
define spinal stenosis:
decrease in size of canal or encroachment of the canal in either vertebral or intervertebral foramen
what is a decrease in size of canal or encroachment of the canal in either vertebral or intervertebral foramen called?
spinal stenosis
define congential spinal stenosis:
born with decreased canal space
what is the condition in which you are born with decreased canal space called?
congenitial spinal stenoisis
define acquired spinal stenosis:
decrease in canal size/space due to:
ligamentum flavum buckling
osteophytes in facet joints
IVD herniation
or DDD (Degenerative Disc Disease) which puts pressure on the roots
what is a decrease in canal space due to ligamentum flavum buckling, osteophytes in facet joints, IVD herniation, or DDD which puts pressure on the roots called?
acquired spinal stenosis
what imaging techniques pick up disc pathologies
CT/MRI’s
where are intervertebral discs found?
Between vertebral bodies from C2-S1
what are the chief bonds between adjacent vertebral bodies?
intervertebral discs
intervertebral discs are thicker anteriorly in ___ and __ spine, therefore gives rise to the ____ nearly uniform in the T-spine
thicker anterior in CERVICAL and LUMBAR spine, therefore gives rise to the LORDOTIC CURVE nearly uniform in the T-spine
are the intervertebral discs vascular or avascular?
avascular except for peripheries
what do the intervertebral discs attach to bone via?
attachment to bone via hyaline articular cartilage - forming an intervertebral symphasis
What two ligaments attach on the anterior and posterior aspects of the IVD’s?
Anterior and Posterior Longitudinal ligaments
intervertebral discs make up what fraction of the total height of the vertebral column?
1/5
in the t-spine the intervertebral discs are ties to the ___ ligaments of the heads of the __
in the t-spine the intervertebral discs are tied to the INTRA-ARTICULAR ligaments of the heads of the RIBS
What two components make up the IVD?
Nucleus pulposus
Annulus fibrosis
which aspects of the annulus fibrosis are thicker, thinner and where is it weaker?
thicker anterior thinner posteriorly weaker in back
what two zones does the annulus fibrosis have?
has a narrow outer collaginous zone and a wider inner fibrocartilaginous zone
annulus fibrosis fibers cross, therefore limiting ___, becomes more aligned closer to ___, therfore ___
fibers cross, therfore limiting ROTATION, becomes more aligned closer to PERIPHERY, therfore WEAKER
the vertical posterior fibres of the of the annulus fibrosis are predisposed to ___
herniation
most problems with the annulus fibrosis are found at what levels?
L5/S1 and L4/L5
what type of movement is the worst for causing disc failure?
translational movement
what % of the nucleus pulposus is water?
88.00%
at birth the nucleus pulposus is ___ material that is replaced later in life by __
at birth, soft gelatinous mucoid material that is replaced later in life by fibrocartilage
which sections of the spine have better developed nucleus pulposus?
better developed in the cervical and lumbar spine
is the nucleus pulposus more elastic or more fibrous and therefore is it flexible or inflexible?
more elastic then fibrous therefore more flexible
is the nucleus pulposus vascular or avascular?
avascular
what is the nucleus pulposus derived from?
derived mainly by annulus fibrosus and hyaline cartilage plates
in the L-spine cellularity is highest in the ___
periphery
what is the nucleus pulposus borderd by superiorly/inferiorly?
hyaline cartilage - can get vertebral end plate fracture as the nucleus pulposus escapes into hyaline cartilage and disrupts the bone
which aspect of the nucleus pulposus is weakest?
weakest and thinnest posterolaterally
what percentage of people with disc bulges don’t have any pain which is caused by pressure on other structures?
80.0%
how do discs gain nutrition?
discs gain nutrition through a sponge-like effect (when decompressed filles with fluid and when compressed fluid is forces out)
define prolapse:
a falling or dropping down of an internal part
what is a falling or dropping down of an internal part called?
prolapse
define herniation:
a protrusion or projection of an organ or part of an organ through the wall of the cavity that normally houses it
what is a protrusion of projection of an organ or part of an organ through the wall of the cavity that normally houses it called?
herniation
What is the role of the lumbar vertebrae as a group?
Weight bearing
What do the vertical trabecular lines allow the bone to do?
Compress slightly with weight bearing – its not just the discs that compress
What muscle merges into the anterior aspect of the vertebral bodies?
The Psoas
What is the clinical implication of Psoas tightness with the vertebral bodies?
It can pull on the vertebrae causing them to anteriorly translate – furthermore if these vertebrae are now in disfunction it will impact the diaphragm as it also shares attachment in the area – the crura tightening due to this disfunction can cause tightening around the esophagus or aorta which can cause even further complication
The vertebral bodies can take a lot of force themselves but what helps to absorb the force anteriorly?
Anterior longitudinal ligament helps to spread the forces among all of the vertebral bodies (force attenuation)
Below and above each pedicle is the inferior and superior ___
vertebral notch
What’s the role of the vertebral body?
Weight bearing Support
The pedicles help to form the ___ which houses the spinal cord
Neural arch
The lamina is the __ of the neural arch
Roof
The neural arch is designed to protect the __
Spinal cord
What comes out of the intervertebral foramen?
Nerve root
The interarticular process are not designed for ___
Weight bearing
What the most important thing to remember/ memorize about the facets?
The orientation of the facets because this dictates what movement they allow
When you have the superior & inferior articular processes together, with the capsule surrounding them it is called
Zygoapophyseal joint
Is the zygoapophyseal … joint weight bearing?
No, only in extension, but can cause complications… think pars interarticularis fracture
How would the body react if there is constant friction between the two articular facets?
Increase osteophyte formation (bone growth)
Is an increase in bone growth in the zygoapophyseal joint normal?
No, because they are not meant to be weight bearing all the time
how could you fix an increase in bone growth in the zygoapophyseal joint?
You can’t reverse the excess bone growth but you can work on posture and mechanics to ensure loading of the articular processes does not occur
What is the benefit of a muscle being attached to a capsule? In this case the multifundus attached to the zygoapophyseal joint.
Helps to increase both mobility and stability, the muscle will have mechanoreceptors to better accommodate forces
What muscle attaches to the front of the vertebral bodies that we use everyday, especially as athletes?
The psoas
What would a tight psoas cause with regard to the spine?
Anterior translation of the vertebral bodies which causes tension to be placed on the facet joint - the patient would come in complaining of facet joint pain with extension and you would treat this condition but the underlying cause would be the tight psoas and you would need to treat this as well
What makes up the boney structures surrounding the vertebral foramen
Pedicles, lamina and posterior aspect of vertebral body
What makes the roof of the neural arch?
Lamina
What happens at the level of L1 with regard to the spinal cord?
The true cord ends
Describe the SP **this is how he will want it explained on a practical exam DETAIL
1 inch long
extends posterior from the junction of the lamina
end is thickened and roughened for muscle and ligamentus attachment
quadrangular, narrow blade of bone
same plane as it’s body
attached are the posterior lamella of the TLF, erector spinae, spinalis thoracis, multifidi, interspinal muscles and ligaments, and supraspinous ligaments
The TP’s of L4-L5 are more stout because the ____ ligament attaches here
iliolumbar ligament
When palpating a patient the TP’s will be found in between the ___, and much deeper… half an inch to and inch lateral and an ___ deep from the SP
SP’s, inch deep
… all measurements matter for practical*
Why do we have lumbar lordosis?
To accommodate for the angle of the sacrum but is also there to help attenuate force
What prevents L5 from sliding forward?
The orientation of the facets- the facets at the level of L5 are largely anterior/posterior (there is a bony block stopping the movement)
What makes up both the roof and floor of the intervertebral foramen?
The pedicles
If you have stenosis within the canal what will it put pressure on?
The spinal cord AND then meninges
Intervertebral discs are designed to increase ___ throughout the entire spine
mobility
If the disc is damaged it will put continuous pressure on the ____ causing immense pain
nerve root
The ring portion of the disc is called the ____
annulus fibrosis
The rings of the disc add ___ to the structure
strength
the disc is not as thick ___
posteriorly
A lot of the fibres are at a __ degree oblique angle and the next layer are the opposite so they alternate and cross one another
30 degree
What is the significance of the oblique angle of the fibres?
It will aid in resisting rotation -The negative to this is yes it resists rotation in both directions but only half of the fibres are being pulled tight depending on the direction of rotation -The implication of this is if you are an athlete who constantly rotates one way only half the disc is resisting movement – therefore creating a weakness as opposed to all fibres resisting the movement
The inside of the disc is called___
The nucleus pulposus
What limitations are caused by the different layers of orientation of the annulus?
Where does this cause weakness?
With respect to rotation it has limitations and it has a weakness posteriorly
When we sit the nucleus of the disc pushes ____
backwards
What is the first thing your going to tell you patient to do if they have a posterior disc herniation
No sitting or forward flexion
What are the fibres of the disc called
The annulus fibrosis
Where does the majority of rotation in the lumbar spine occur?
L5 and S1
The disc will become more ___ as we age (due to less water content)… therefore decreased ___ and resistance to movement, forces etc.
fibrocartilaginous, mobility
Outside of the periphery the disc is largely avascular - what are the implications?
implication is a long healing time as it takes time for nutrients to reach it
A prolapse is the start of a ____
herniation
The nucleus is always pushing out on the fibres of the ___
annulus fibrosis
Where is the weakest part of the annulus fibrosis?
posteriorly
If a patient comes in with L5-S1 disc prolapse, no pain in their back, tingling after sitting near the end of the day, down the dermatomal pattern of L5 – what advice would you give them?
Pillow behind lumbar spine Take breaks and stand whenever possible Ensure no excessive forward flexion when at computer – ex. Proper ergonomics Educate – flexion, rotation when carrying things Engage core and glutes – protecting the spine Proper mechanics of getting in/out of car Do as much as you can at home standing Brace core and bend knees when coughing
