Cervical spine Flashcards
Standing Lateral view:
- Pt position
- Central beam
- pt position - standing lateral view places the pt with the head in neutral
- central beam - directed horizontally to the center of C4 vertebra
Lying Lateral View
- pt position
- central beam
- pt position - supine with head in neutral position
- central beam - horizontally to a point approx 2.5-3 cm caudal to mastoid tip
- important the film demonstrates C7 vertebrae
What do you see on lateral views?
- vertebral bodies
- apophyseal joints
- spinous processes
- intervertebral disc
- suffices for most traumatic injuries and is most important view
- A/P arches of C1
- The odontoid process in the atlanto-dens interval
What is the atlanto-dens interval? What should the Atlanto-dens interval not exceed?
space between odontoid and anterior arch of atlas
- should not exceed 3 mm in adults whether flexed or extended
- in children under age 8, distance has been as much as 4 cm with flexion
What are the 5 contour lines of the normal cervical spine?
- Anterior vertebral line
- posterior vertebral line
- spinolaminar line
- posterior spinous line
- clivus-odontoid line
What should the retropharyngeal space be? what should the retrotracheal space be?
retropharyngeal(RF) = <7mm
- important for atlanto-atlaxial translation
retrotracheal = <22mm adults, <14mm kids
Line drawn from posterior margin of the foramen magnum to the dorsal margin of the hard plate
Chamberlain line
What should the odontoid process projection remain to be considered normal with regards to the chamberlain line? what does it indicate if it is abnormal
< 3mm = normal
3-6 mm = abnormal
> 6mm = strongly suggests cranial settling
Line defines the opening of the foramen magnum and connects the anterior margin with posterior margin of the foramen magnum
McRae line
What should the odontoid process projection remain to be considered normal with regards to the McRae line? what does it indicate if it is abnormal
below line = normal
indicates atlantoaxial impaction (cranial setting)
AP view:
- pt position
- Central beam
- structures seen
- pt position - standing or supine
- Central beam - directed toward C4 vertebra at an angle of 15-30 degrees cephalad
- structures seen - C3-C7 vertebral bodies and the intervertebral disk spaces
- limitation = C1-2 not adequately seen; open and close mouth rapidly = allows C1-2
open mouth view:
- pt position
- Central beam
- structures seen
- pt position - same as AP view but mouth opens as wide as possible
- Central beam - perpendicular to the midpoint of the open mouth
- structures seen - Best to demonstrate C1-2
Fuchs view:
- pt position
- Central beam
- structures seen
- pt position - supine on table with neck hyperextended
- Central beam - directed vertically to the neck just below the tip of the chin
- structures seen - odontoid process (considered if open mouth view is insufficient)
Oblique view:
- pt position
- Central beam
- structures seen
- pt position - obtained in AP or PA view; pt is rotated 45 to one side
- Central beam - directed to C4 vertebra with 15-20 cephalad angulation
- structures seen - intervertebral neural foramina; visualize fxs of the neural arch and abnormalities of the neural foramina and apophyseal joints
(rotated right will demonstrate the left-sided neural foramina
Swimmers view:
- pt position
- Central beam
- structures seen
- pt position - prone with left arm abducted and the right arm on the side
- Central beam - horizontally toward left axilla, film cassette on right side of the neck
- structures seen - demonstration of C7-T2 visualization
- always visualize C7** bc injuries will be missed if it is not
Occipital condyle fractures require high degree of suspicion by investigator. Advanced imaging (CT) will be used. They are very unstable injuries. What are the types of occipital condyle fractures?
Type I - impacted occipital fracture; axial loading MOI
Type II - component of basilar skull fracture; direct blow to skull
Type III - avulsion fracture of the condyle toward the tip of the odontoid; cervical rotation and lateral bending MOI; most concerning with associated instability
Axial load transmitted symmetrically through the cranium and occipital condyles into the superior surfaces of the lateral masses of the atlas and drives the masses outwards; symmetrical fracture of the A and P arches of C1 which is associated with disruption of the transverse lies; unilateral occipital headache and neck pain are clinical characteristics
Jefferson fx
- open mouth AP view best
- may require additional CT
MOI: hyperextension and distraction; fracture ID’d through the pedicles of C-2 and associated ligament disruption and intervertebral disk injuries
Hangmans fracture
- lateral view is best
MOI: axial load that results in fractures to lower cervical spine (C3-C7); nucleus pulpus is driven through the fractured vertebral plate into the vertebral body causing a comminuted fracture
Burst fracture
- CT most revealing
MOI: Compression and flexion; most severe and most unstable Cspine injury; characterized by posterior displacement into the spinal canal, fracture of posterior elements, and disruption of soft tissues
Teardrop fracture
- lateral view is best, but requires MRI
- major concern for football
- results in acute anterior cord syndrome = loss of motor function and sensation
MOI: caused by acute powerful flexion (shoveling) or direct blow to the cervical spine; stable fx with the posterior lig complex remaining intact; C7 should always be ID’d
Clay-shovelers fx
- usually in C6 or 7
- swimmers view if C7 can’t be visualized from lateral view
MOI: hyperflexion of the Cspine; anterior compression of the vertebral body is misshaped into a wedge rather than block; posterior lig complex is stretched but remains in tact
Compression (wedge) fx
- lateral view
What is the worst odontoid fx?
Transverse fracture of the odontoid
- best viewed by AP view with open mouth
- Fuchs and lateral as well
What are the Canadian Cspine rules?
- High risk factors = age > 65, dangerous mechanism of injury (fall from >3ft or 5 stairs, axial load to the head, MVA high speed/ rollover/ejection, motorized rec vehicles, or bicycle struck), or numbness/ tingling in extremities
- if patient has low risk factors (simple rear-end MVA, sitting in ED, ambulatory, delayed onset of neck pain, or absence of midline tenderness) but unable to rotate 45 degrees
