Cervical Spine Flashcards
1
Q
Standard projections of cervical spine:
A
AP
lateral views
2
Q
When is swimmer’s lateral projection performed?
A
necessary to assess lower cervical segments and cervicothoracic junction
3
Q
What view should be ordered with trauma cases with suspicion of cervical spine fracture?
A
cross-table lateral, AP, and APOM views
patient immobilized
4
Q
When are bilateral oblique projections obtained?
A
when assessment of neural foramina necessary
5
Q
What can flexion-extension lateral views asses?
A
instability
6
Q
Examination of pediatric patients at high risk for instability, should have what view?
A
active lateral flexion/extension view
7
Q
CT for cervical spine is more sensitive detecting what?
A
subtle injuries and better at visualizing craniovertebral and CT junctions
8
Q
When is MRI for cervical spine recommended?
A
recommended for any patient with neurological deficit for its ability to demonstrate position of bony fragments as well as injury to spinal cord, disk, and soft tissues
9
Q
What are the evidence based guidelines to help determine if a patient needs radiographic examination?
A
Canadian C-Spine Rule (CCR)
National Exmergency X-Radiography Utilization Study (NEXUS)
10
Q
Who does CCR apply to?
A
patient who are alert and medically stable
11
Q
CCR definition
A
Tool designed to decide whether conventional radiography of c-spine necessary for patients who have sustained traumatic injury involving head o
12
Q
What questions does the CCR ask?
A
- Are there any high-risk factors that mandate radiography?
- Are there any low-risk factors that allow safe assessment of ROM?
- Is patient able to rotate neck actively at least 45° to right and left?
13
Q
What are examples of high risk factors?
A
older than 65
dangerous MOI
parenthesis in extremities
14
Q
What are examples of low risk factors that allow for assessment of ROM?
A
simple rear-end motor vehicle accident normal sitting position patient ambulatory at any time delayed onset of neck pain absence of mid-line cervical spine tenderness
15
Q
What is CCR sensitivity and specificity?
A
sensitivity: 100%
specificity: 43%
16
Q
What is NEXUS?
A
low-risk criteria developed to help identify patients following trauma who do not need diagnostic imaging for c-spine based on their clinical presentation
17
Q
What are the guidelines for NEXUS:
A
No posterior midline cervical tenderness No evidence of intoxication Normal level of alertness and consciousness No focal neurological deficit No painful distracting injuries
18
Q
What is NEXUS sensitivity and specificity?
A
sensitivity: 99.6%
specificity: 12.9%
19
Q
What are the ACR recommendations if a patient meets CCR and NEXUS criteria?
A
CT with sagittal and coronal reformatting or both CT and MRI as complementary studies to assess instability or myelopathy
20
Q
If patient has a history of trauma, what is viewed first?
A
lateral view if not being evaluated at trauma center wit advanced imaging
21
Q
What do lateral views allow for?
A
assessment of normal cervical alignment with series of parallel vertebral lines
22
Q
How is the cross-table lateral view performed?
A
in severe trauma cases, performed on supine, immobilized patient
preliminary diagnostic screen
23
Q
What does the lateral flexion/extension view stress?
A
views performed to expose excessive segmental motion during functional movement
24
Q
What do stress view give joint?
A
more opportunity to reveal instability by imposing mechanical stress
25
What does evaluation of radiographs for significant signs of cervical trauma include:
soft tissues
vertebral alignment
joint characteristics
26
What are abnormal soft tissue signs?
1. widened retropharyngreal or retrotracheal spaces
2. displacement of trachea or larynx
3. displacement of prevertebral fat pad
27
What is the prevertebral tissue distance in adults?
6 at 2 and 22 at 6
28
What do abnormal vertebral alignment signs include?
1. loss of parallelism
2. loss of lordosis
3. acute kyphotic angulation with widened interspinous space
4 rotation of vertebral body
29
What does loss of parallelism indicate?
fracture, dislocation, or severe degenerative changes
30
What does loss of lordosis indicate?
muscle spasm in response to underlying injury
31
What does acute kyphotic angulation with widened interspinous space
indicate?
rupture of posterior ligaments
32
What does rotation of vertebral body indicate?
unilateral facet dislocation, hyperextension fracture, muscle spasm, or disk or capsular injury
33
What is included in abnormal joint signs?
1. widened ADI
2. widened interspinous process space
3. widened IVD space
4. narrowed IVD space
5. loss of facet joint articulation
34
What does widened ADI indicate?
degeneration, stretching, or rupture of transverse ligament
35
What does widened interspinous process space (fanning) indicate?
rupture of interspinous and other posterior ligaments
36
What does widened IVD space indicate?
posterior ligament rupture
37
What does narrowed IVD space indicate?
rupture of disk and extrusion of nuclear material
38
What does loss of facet joint articulation indicate?
dislocation
39
What are stable injuries?
protected from significant bone or joint displacement by intact posterior spinal ligaments
40
What is an example of a stable injury?
compression fractures, traumatic disk herniations, and unilateral facet dislocations
41
What is an unstable injury?
show significant displacement initially or have potential to become displaced with movement
42
What are examples of unstable injury?
fracture–dislocations and bilateral facet dislocations
43
What are the most frequently injured levels?
C1-C2
| C6-C7
44
What do adults usually injure?
lower c-spine
45
What are children more likely to injure?
upper c-spine
46
What portion of all spine cord injuries occur in c-spine?
2/3
47
What is SCIWORA?
spinal cord injury without radiographic abnormalities syndrome
48
Who is SCIWORA predominant in?
children with inherent elasticity in pediatric spine
49
What does SCIWORA cause in children?
ligamentous injury and cartilaginous vertebral endplate fractures
50
What can result in central cord syndrome?
adults, acute disk prolapse and/or excessive buckling of ligamentum flavum into canal already compromised by posterior vertebral body
51
Mechanisms of injuries of fractures are classified how?
direct
| indirect
52
What are the two fracture configurations seen in c-spine?
avulsion fractures
| compression/impaction fractures
53
How do avulsion fractures occur?
as bone fragment pulled off by violent muscle contraction or by passive resistance of ligament applied against an oppositely directed force
54
What is the result when adjacent vertebrae are forced together?
compression or impaction fracture
55
What does an axial compression force produce?
comminuted or burst fracture of impacted vertebral body
56
What do flexion forces produce?
compresses impacted vertebral body into an anterior wedge shape
57
What do extension forces do?
fractures and compresses articular pillar
58
What are some commonly seen fractures of C3-C7?
```
wedge
burst
teardrop
articular pillar
clay shoveler's
transverse process fracture
```
59
What is a wedge fracture?
occurs when an interposed vertebra is compressed anteriorly by two adjacent vertebrae owing to hyperflexion forces
60
Where do a majority of wedge fractures happen?
2/3 in c-spine at C5,C6 or C7
61
Why can wedge fractures be stable?
because ligamentous structures are at least partially intact
62
What a burst fracture?
occurs when IVD axially compressed and NP driven through an adjacent vertebral endplate, causing literal bursting apart of vertebral body and resulting in comminution
63
Is a burst fracture stable or unstable?
either, depending on fracture configuration
64
What is a teardrop fracture?
occurs when triangular fragment of bone becomes separated from anteroinferior corner of vertebral body
65
What causes a teardrop fracture?
either avulsion force sustained during hyperextension or compressive force sustained during hyperflexion
66
What is the most severe of lower cervical fractures?
flexion teardrop fracture
67
What can posterior displacement of vertebral body cause?
anterior cord compression resulting in quadaplegia
68
What is an articular pillar fracture?
fractured by a compressive hyperextension force combined with a degree of lateral flexion
69
Where does a articular pillar fracture most frequently occur?
C6
70
Is an articular pillar fracture stable or unstable?
stable
71
What is a clay shoverler's fracture?
avulsion fracture of SP produced by hyperflexion forces or forceful muscular contraction of trapezius/rhomboids
72
What is often associated with a clay shoveler's fracture?
repetitive heavy labor of upper extremities
73
Where does a clay shoveler's fracture more frequently occur?
at C6, C7 and T1
74
Is a clay shoveler's fracture stable or unstable?
stable
75
What is a transverse process fracture?
uncommon, but usually occurs at largest TVP in c-spine (C7)
76
What does a transverse process fracture result from?
lateral flexion forces causing an avulsion at tip of contralateral TVP
77
If instability suspected without neurological complaint, what view is taken?
flexion and extension stress views
78
What is conservative treatment for stable fractures?
rigid orthosis
79
How are dislocations desribed?
by directions that superior vertebra segment moved
80
What are the most serious and life-threatening injuries to c-spine?
fracture-dislocations
81
What is Hangman's fracture usually associated with?
anterior dislocation of C2 on C3
82
What causes a fracture-dislocation of atlantoaxial joint?
fracture through base of dens combined with ligament rupture
83
What may cause vertebral body to displace anteriorly transecting or contusing spinal cord?
fractures of posterior vertebral structures combined with tears of posterior ligaments
84
Dislocations not associated with fractures maybe either"
complete or self reducing
85
What are self reducing dislocations?
force momentarily disengages articulations, which then return to normal alignment once force dissipates
86
Complete facet dislocation may occur:
unilaterally
| bilaterally
87
What does unilateral facet joint dislocation result from?
flexion- rotation force
88
What does bilateral facet joint dislocation result from?
hyperflexion force
89
What are locked facets?
when inferior articulating process of uppermost vertebra will lie in front of superior articulating process of subjacent vertebra-locking out normal articulation
90
What does unilateral facet dislocations tear?
one facet capsule and posterior ligaments
91
When is unilateral facet dislocation a stable injury?
absence of vertebral body subluxation
92
Why are bilateral facet dislocations unstable?
because extensive disruption of posterior ligaments, facet joint capsules, annulus fibrosus and sometimes anterior longitudinal ligament
93
When does atlantoaxial rotary subluxation occur?
when forces of flexion or extension combine with rotation to cause one inferior facet of C1 to slip anterior to superior facet of C2 and become fixed in this position
94
What does reduction involve?
traction techniques supplemented by active ROM exercises to restore alignment
95
Cervical sprains are injuried to what?
ligaments of spine
96
What do hyperflexion sprains disrupt?
posterior ligament complex
97
What do tears of posterior ligaments allow?
superior vertebra of segment to rotate or translate anteriorly on it subjacent vertebra
98
When do hyperextension sprains result?
when neck forced past end ranges of extension
99
What do hyperextension sprains disrupt?
anterior ligaments and soft tissues, resulting in transient posterior subluxation of vertebral segment
100
What leads to degenerative disk disease (DDD)?
degeneration of IVDs
101
What leads to degenerative joint disease (DJD)?
osteoarthritic changes at synovial facet joint
102
What is foraminal encroachment?
diminished normal dimensions of IVF secondary to degenerative changes in adjacent structures
103
What is spondylosis?
osteophyte formation at joint margins
104
What is spondylosis deformans?
advance spur formation from degeneration of vertebral bodies
105
What is diffuse idiopathic skeletal hyperostosis (DISH)?
flowing ossification along anterior vertebral bodies and disk space
106
What is included in degnerative changes in disk?
dehydration, nuclear herniation, annular protrusion, and fibrous replacement of annulus
107
What does DDD present with?
Schmorl's nodes and vacuum phenomenon
108
What is the radiographic hallmark of DDD?
decreased height of disk space
109
How are Schmorl's nodes identified?
radiolucent focal defects in vertebral endplates
110
How does vacuum phenomenon present?
horizontally oriented radiolucency within disk space
111
Why are facet joint vulnerable to DJD?
great mobility of c-spine, postural strains, and repetitive occupational or recreational actions that contribute to abnormal tissue and joint biomechanics
112
What are the hallmark images of DJD?
decrease in joint space, subchondral sclerosis, and osteophytosis
113
What is foraminal encroachment a result of?
result of degenerative changes in adjacent structures (including DDD and DJD) that diminish size of IVF
114
How is encroachment seen on film?
narrowing of radiolucent ovals that represent
115
What is cervical spine spondylosis in response to?
formation of osteophytes in response to DDD
116
Where is osteophyte formation most prominent in cervical spine spondylosis?
points in curvatures of spine farthest from center of gravity line, or at apices of concavities, as result of greater segmental mobility
117
What are the c-spine site of osteophyte formation in cervical spine sponydlosis?
C4-C5
| C5-C6
118
What is spondylosis deformans?
degenerative condition characterized by anterior and lateral vertebral endplate osteophytosis that results from anterior or anterolateral disk herniation
119
What images demonstrate osteophytes in spondylosis deformans?
AP or lateral
120
What is DISH associate with?
diabetes, growth hormone, vitamin A or retinoid derivatives, and metabolic syndromes
121
What age and sex is DISH associated?
age 40, more frequently with men
122
What is the most common site for DISH?
middle to lower thoracic spine and upper lumbar spine, as well as lower cervical spine
123
What are clinical symptoms of DISH?
mild pain and stiffness
124
How is DISH assessed?
Assessed on lateral view, three radiographic criteria define DISH
125
How is DISH distinguished from spondylosis deformans?
1. Flowing ossification along anterolateral aspects of at least four contiguous vertebral bodies
2. Relative preservation of disk height and absence of radiographic evidence of DDD
3. Absence of facet joint DJD or sacroiliitis
