spine ch 23 Flashcards
what is the study of choice for most diseases of spine
MRI because of
- its ability to visualize and detect abnormaities in soft tissues, such as bone marrow, the cpinal cord, and the intervertebral disks;
- its ability to display images in any plane
- and the lack of radiation
Components of almost every vertebra
Almost every vertebra has a
- body composed of inner cancelous bone and marrow and
- posterior elements made of compact dense bone consisting of the pedicles, laminae, facets, transverse processes and a spinous process.
what vertebrae are rectangular in shape
from the level of c3-L5
what type of joint are facet joints? (superior and inferior articular processes joint)
true synovial joint
Where are two ovoid pedicles not visible?
at the level L5 because of lordosis of the lumbar spine
Relative height of the disk space varies in each aprt of the spine. How is it in : - cervical spine - thoracic spine - lumbar spine
- In the cervical spine, the disk spaces are about equal to each other in height.
- In the thoracic spine, they are usually slightly decreased in size from the cervical spine, but equal in height to each other
- In the lumbar spine, the disk paces progressively increase in height with each successive interspace, except for L5-S1, which can be equal to or slightly less than the height of L4-L5
What structure does “Scottie dog” represent
oblique view of lumbar spine: ear: superior art facet leg : inferior art facet nose- transverse process neck: pars interarticularis
Where does spinal cord end
spinal cord extends from the medulla oblongata to the level of L1-L2, ending as the conus medullaris
how are spinal nerves named
- from c1-c7, they exit above the vertebrae that they are named after
- C8 nerve exits between the 7th cranial and 1st thoracic vertebrae
- remaining nerves exit below their respectively numbered vertebrae.
On T1-weighted saggital MRI images of the spine, the vertebral bodies, containgin bone marrow will be of ____ signal intensity, the disks will be ____ in signal intensity.
vertebral bodies - high signal intensity = bright
disks - low signal intensity dark
On conventional T2 weighted images, the vertebral body will be _____ compared to disks.
CSF will appear ____.
on T2, vertebral bodies will be slighlty brighter than disks.
CSF will be bright
Cortical bone is ____ on all sequences.
dark
List some of the causes of back pain
- herniation of an intervertebral disk
- degenerative disk disease
- osteoarthritis of facet joints
- diffuse idiopathic skeletal hyperostosis (DISH)
- compression fractures of the spine
- spinal stenosis
In the lumbar region, disk herniation may lead to ___ and ___, whereas herniation of a cervical disk may produce ___ and ____.
lumbar : back pain and sciatica
cervical : radiculopathy and myelopathy
study of choice for evaluating herniated disk is?
MRI
In the cervical spines disk herniations occur most frequently at what levels?
C4-C5, C5, C6 and C6-C7
Majority of disk herniation occur at what levels?
at the lower three lumbar disk levels, L3-L4, L4-L5, L5-S1
What will lead to disk material bulging?
- Degeneration of the outer annular fibers of the disk or
2. trauma that leads to an interruption in those fibers
What study is useful in differentiating persistent or recurrent disk herniation from scar formation?
gadolinium-enhanced MRI studies of the spine
when the annular fibers rupture, the nucelus pulposus may herniate (usually _____ /direction) through ______.
when the annular fibers rupture, the nucelus pulposus may herniate (usually posterolaterally) through weakend area of the posterior longitudinal ligament. .
Degenerative disk disease leads to
progressive loss of the height of the intervertebral disk space
