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Flashcards in XR Deck (25)
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Basic Views of C-Spine

AP, AP Open Mouth, Lateral (need to include T1 and see prevertebral tissues), B/L Oblique, Flex/Ext


Cervical Spine Open Mouth

see dens, lateral masses should be symmetrical, C1/C2 alignment


`Cervical AP View

uncovertebral joints, TPs, SPs (want to see alignment of SPs)


Cervical Lateral

*Need to see all 7 vertebrae and T1, ant + post columns (bodies), Intervertebral disc space, SPs, facet joints, prevertebral soft tissue (more for trauma pt's want to see ant to vertebral bodies)


Normal Variants in Lateral C-Spine XR

pseudosubluxation of C2 and C3, normal in children
Predental Space (from dens to C1 arch), normally 3mm in adults, 5mm in children


C Spine Oblique

see neural foramina, facet joints, and pedicles


C Spine Flex/Ext

helps detect ligamentous injury (instability) that not apparent in neutral view


C SPine Flex/Ext Sx of instability

in flex view: 3.5mm translation displacement (shouldnt be more than 1mm), 1.7mm+ disc space widening, angulation of >11degrees in contiguous vertabrae


atlanto-dens interval (ADI) for instability

- in children <3mm
- interlaminar and interspinous distances should remain symmetric while facet jts and intervertebral disc spaces shouldnt widen


Dens Fx

Type I: <5%, Fx through tip of dens at insertion of alar ligament, usually stable
Type 2: Most common; fracture throught dens, UNSTABLE
Type 3: Subdentate (through body of C2); stable


Flexion Injuries: 1. ant dislocation, 2. wedge, 3. unstable wedge; 4. u/l interfacet dislocation; 5. b'l interfacet dislocation; 6. flexion teardrop

1. hyperflexion sprain, ant dislocation with interspinous lig tear; 2. ant vert body fx; 3. ant wedge with ligament damage; 4. u/l facet jump; 5. jumped facets with anterolisthesis; 6. large fx of ant body with post ligamentous damage


atlanto-occipital disassociation

decapitation, usually fatal


jumped facets

dislocation of vertebral facet joint in which inf articular facet of sup vertebra lies ant to the superior articular facet of inf vertebra
- can be u/l (50%)
- imaging: anteriorlisthesis, widening of interspinous distance and facet joint


Extension injuries: 1. hangman's Fx; 2. ext teardrop; 3. hyperext w/pre-exist spondylosis

1. Fx @ pedicles, vertebral arch separates from body; 2. anterior teardrop with tear of ALL; 3. looks like a tear of the IV disc


Hangman Fx

Fx involving both pars articularis of C2, 2/2 to hyperext and distraction; imaging shows fx's of b/l lamina and pedicles and usually anterolisthesis at C2-C3


Jefferson Fx

Burst Fx of C1- usually ant and post arches; 2/2 to axial loading (ie diving on head)
imaging: open mouth lateral offset of C1 on C2, lateral view shows widening of atlantodens interval if traversing lig damaged


unstable cervical Fxs

Flex: B/l interfacetal dislocation; flexion teardrop Fx, wedge Fx w/post lig rupture
Ext: odontoid Fx type II; hangman's Fx, ext teardrop fx
Vert Compression: burst


Lumbar Lateral Spine XR

IV disc spaces, SPs, pedicles, alignment, vertebral body height


Scotty Dog Sign

post elements of lumbar spine form figure of Scotty Dog in lumbar oblique view (nose- TP, eye- pedicle, front leg- inf articular facet, ear- sup art facet, neck- pars interarticularis), Fx of neck= pars defect



one vertebra slips forward (anterolisthesis) or backward (retrolisthesis), compared to the next vertebra below


5 types of spondylolisthesis

1. dysplastic: defect in formation in part of vertebra (can be congenital)
2. Isthmic: caused by defect in pars interarticularis
3. degenerative: caused by djd
4. traumatic: caused by direct trauma; usually fx of pedicle, lamina, or facet joints
5. pathologic: caused by abnormal bone (ie tumor)


Grades of Spondylolisthesis

1= 0-25%
2= 25-50%
3= 51-75%
4= 76-100%
5= >100% or spondyloptosis



pars defect; defect of lumbar vertebra at the pars interarticularis which is ant to lamia and post to pedicle; typically 2/2 to stress fx from repetitive injury



degenerative change


Flexion Fxs of Thoracic/ Lumbar

1. compression fx: ant vertebral body breaks/ loses height while posterior is intact. Usually stable.
2. axial burst fx: