Cervical Spine Flashcards
What are the 3 standard views of the cervical spine?
- Anteroposterior (AP)
- APOM
- Lateral views
What projection is necessary to assess the lower cervical segments and the cervicothoracic junction?
Swimmer’s lateral projection
What projection is necessary to assess the neural foramina?
Bilateral oblique projections
What projections can assess instability?
Flexion-extension lateral views
Which diagnostic imaging technique is most sensitive to detecting subtle injuries and better at visualizing craniovertebral and cervicaotheroacic junctions?
CT
Which diagnostic imaging technique is recommended for any patient with neurological deficit? Why?
MRI, because of its ability to demonstrate position of bony fragments as well as injury to spinal cord, disk, and soft tissues
What are the 3 significant injury types in which radiographic examination is not necessary?
fracture, dislocation, or instability
What are the 2 evidence-based guidelines established to help the clinician decide if a patient has the potential for a significant c-spine injury and if radiographic examination is necessary or not?
- Canadian C-Spine Rule (CCR)
- National Emergency X-Radiography Utilization Study (NEXUS)
The Canadian C-Spine Rule (CCR) applies to what type of patient?
Those who are alert and medically stable
What is the Canadian c-spine rule designed to decide?
whether conventional radiography of the cervical spine is necessary for patients who have sustained a traumatic injury involving the head or neck
What are the 3 questions that are asked during the Canadian C-spine Rule?
1) Are there any high-risk factors that mandate radiography?
2) Are there any low-risk factors that allow safe assessment of ROM?
3) Is patient able to rotate neck actively at least 45° to right and left?
What are 3 examples of high-risk factors that mandate radiography?
- age greater than 65
- dangerous MOI
- numbness of tingling in the extremities
What are the 4 low-risk factors that allow safe assessment of ROM?
- simple rear-end motor vehicle accident
- normal sitting position
- patient being ambulatory at any time
- delayed onset of neck pain
- absence of midline cervical spine tenderness
If the answer to one of the low-risk factors is no, what is the next step?
obtain radiographs
If the answer to one of the low-risk factors is yes, what is the next step?
move to question #3
If the patient is unable to rotate their neck actively at least 45° to right and left what is the next step?
obtain radiographs
The CCR has a sensitivity of __% and a specificity of __%
100%
43%
A test with high sensitivity is good at ruling ____ a disorder if the test is negative.
out
A test with high specificity is good at ruling ____ a disorder if the test is positive.
in
Define sensitivity
A test’s ability to obtain a positive test when the target condition is really present
***true positive
Define specificity
A test’s ability to obtain a negative test when the condition is really absent
***true negative
What is the NEXUS designed to do?
Determine whether or not patients need diagnostic imaging for c-spine based on their clinical presentation following trauma.
What are the 5 low-risk criteria in which, according to the NEXUS, if the patient does not exhibit will not need radiography?
- No posterior midline cervical tenderness
- No evidence of intoxication
- Normal level of alertness and consciousness
- No focal neurological deficit
- No painful distracting injuries
The NEXUS has a sensitivity of __% and a specificity of __%
- 6
12. 9
In summary, what are the 5 circumstances in which patients who have sustained acute trauma should have radiography?
- Dangerous MOI (diving accident, fall from height, motor vehicle accident)
- greater than 65 years of age
- Paresthesias in extremities
- Midline tenderness over spine
- Unable to rotate neck 45° to left and right
If a patient meets the clinical criteria of the CCR or NEXUS guidelines, what type of imaging should be performed?
CT with sagittal and coronal reformatting
OR
both CT and MRI as complementary studies to assess instability or myelopathy
What view should be the first radiograph evaluated if patient has a history of trauma and is not being evaluated in a trauma center? Why?
Lateral, because it allows for the assessment of normal cervical alignment with series of parallel vertebral lines
What view should be evaluated in severe trauma cases? Why?
A cross-table lateral view, because it is performed in supine, with the patient immobilized
What are the lateral flexion/extension stress views used to expose?
excessive segmental motion during functional movement
What are 3 abnormal soft tissue signs in the cervical spine?
- Widened retropharyngeal or retrotracheal spaces
- Displacement of trachea or larynx
- Displacement of prevertebral fat pad
There should be _ mm of space between C2 and the prevertebral soft tissue shadow
6
There should be _ mm of space between C6 and the prevertebral soft tissue shadow
22
What are 4 abnormal vertebral alignment signs in the cervical spine?
- Loss of parallelism as outlined for lateral view
- Loss of lordosis
- Acute kyphotic angulation with widened interspinous space
- Rotation of vertebral body
What does a loss of parallelism as outlined for lateral view, indicate?
fracture, dislocation, or severe degenerative changes
What does a loss of lordosis indicate?
muscle spasm in response to underlying injury
What does acute kyphotic angulation with widened interspinous space indicate?
rupture of posterior ligaments
What does rotation of a vertebral body indicate?
unilateral facet dislocation, hyperextension fracture, muscle spasm, or disk/capsular injury
What are 5 abnormal vertebral joint signs in the cervical spine?
- Widened ADI
- Widened interspinous process space (known as “fanning”)
- Widened IVD space
- Narrowed IVD space
- Loss of facet joint articulation
What does a widened ADI indicate?
degeneration, stretching, or rupture of the transverse ligament
What does a widening of interspinous processes indicate?
rupture of interspinous and other posterior ligaments
What does a widening of the IVD space indicate?
posterior ligament rupture
What does a narrowing of the IVD space indicate?
rupture of disk and extrusion of nuclear material
What does a loss of facet joint articulation indicate?
dislocation
Describe the difference between stable and unstable injuries
- Stable injuries are protected from significant bone or joint displacement by intact posterior spinal ligaments
- Unstable injuries show significant displacement initially or have potential to become displaced with movement
What are some examples of stable injuries?
- compression fractures
- traumatic disk herniations
- unilateral facet dislocations
What are some examples of unstable injuries?
- fracture dislocations
- bilateral facet dislocations
Which levels of the cervical spine are most frequently injured?
C1–C2 and C6–C7
Adults characteristically injure their ____ c-spine and children more frequently injure their ____ c-spine
lower
upper
Cervical spine fractures are associated with what 40% of the time?
neurological injury
What percentage of all spinal cord injuries occur in the c-spine?
⅔
What does SCIWORA stand for and what is it?
Spinal Cord Injury Without Radiographic Abnormalities
It is a type of spinal cord injury that occurs without fracture or dislocation
What type of patient is SCIWORA syndrome most common? Why?
Children, because of the inherent elasticity in the pediatric spine
What are the 2 classifications of fracture MOIs?
direct force or indirect force
Describe the difference between direct and indirect fracture MOIs
- direct force, such as blow to head
- indirect force, such as rapid acceleration/deceleration in motor vehicle accident