Ucsf: Video E 48 Part 2 Msk Skeletal Trauma (Learning Radiology-Cervical Spine)

Front 1

What are the 3 rules of 3 of cervical spine

What are the major C-spine fractures

Back 1

predentate space should be less than 3mm
prevetebral soft tissue at C3 is 3mm
anterior wedging of 3mm or more suggest a compression fracture

jeffersons (burst of C1)
hangmans (pars of C2)
extension teardrop (anterior inferior avulsion)
burst
clay shovelers (spinous process)
perched/locked facets and alantoaxial dislocation (ligament injury)

Front 2

What are the 3 parallel lines of the c-spine

Back 2

anterior bodies (anterior long ligament)
posterior bodies (posterior long ligament)
Spinolaminar white line

Front 3

What is the spinolaminar white line

Back 3

the junction between the spinous process and the lamina

Front 4

What is the mechanism of alantoaxial dislocation

Back 4

hyperflexion

Front 5

What is th relative movement of C1 and C2 in an alantoaxial dislocation

Back 5

C1 forward on C2

Front 6

Are neurologic injuries common with alantoaxial dislocations

Back 6

yes

Front 7

What measurement is increased in an alantoaxial dislocation

What is the cause of alanto-axial disassociation

Back 7

predentate space

Forward movement of the atlas on the axis is normally restricted by the transverse ligament
The transverse ligament is the primary restraint against atlantoaxial, anteroposterior movement. Alanto axial disassoication will occur if this ligament is injured

Front 8

What is the most common fracture of C1

Back 8

neural arch fracture

Front 9

What is the mechanism of a neural arch fracture

Back 9

hyperextension

Front 10

What is a common pitfall of a neural arch fracture

Back 10

congenital anomaly

Front 11

What does the atlas (c-1) and axis (C-2) look like

Back 11

Front 12

What part of the atlas (C-1) is fractured in a burst fractue

Back 12

anterior and posterior arches of the neural arch

Front 13

What is the mechanism of a burst fracture

Back 13

compressive force such as diving accident

Front 14

What is another name for a burst fracture

Back 14

jefferson fracture

Front 15

What is the best way to evaluate a burst (jefferson) fracture using plain film

Back 15

open mouth view

Front 16

What does an open mouth view look like

Back 16

Front 17

What is the most common fracture of C2

Back 17

hangmans fracture

Front 18

Describe a hangmans fracture of C2

Back 18

fracture through pedicles or pars of C2 with anterior slip of C2 on C3 (pedicle and pars are used interchangeable when refering to C2. This is bc the exact anatomy is not agreed on)

This results in anterior subluxation of the anterior vetebral body (dens) of C2

Also there is posterior displacement of the posterior element of C2

Front 19

What is the MC cause of a hangmans fracture

Back 19

hyperextension compression (MVA)
(chin on dashboard)

Front 20

Are hangmans fractures associated with neuroloical defect

Back 20

no if associated with MVA

Front 21

What fracture is associated with an hangmans fracture

Back 21

a teardrop avulsion fracture of the anterior-inferior aspect of C2

Front 22

What is the MC cause of a dens fracture

Back 22

hyperextension injuries

Front 23

What is the movement of C1 and C2 with a dens fracture

Back 23

forward subluxation of C1 on C2

Front 24

What are the 3 major types of dens fractures

Back 24

tip of dens (5%)
base of dens (65%)
sub-dentate (30%)

Front 25

What is the mc type of dens fracture

Back 25

base of dens

Front 26

What are 3 pitfalls to dens fractures

Back 26

Mach-lines
Non-union ossification centers
Non-union of previous fracture

Front 27

What is a mach line

Back 27

Mach bands are an optical phenomenon in which dark
and light lines appear at the borders of structures of different radiodensity on radiographs. I

Front 28

What type of film is a mach line of the base of the dens seen
(plain film)

Back 28

coronal and the lateral film should be checked to determine if it is truly a fracture

Front 29

Where is the mach line seen at the base of the dens

Back 29

where the C1 anterior arch overlaps the bens

Front 30

What is the mechanism of a C3-C7 burst fractures

Back 30

axial loading from MVA

Front 31

Do burst fractures commonly result in comminuted vertical fractures through the vetebral body

Back 31

yes

Front 32

What should be carefully looked for in a pt with a burst fracture

Back 32

fragments that are retropulsed into the spinal canal

Front 33

Do burst fractures sometimes result in a flexion tear drop fracture

Back 33

yes

Front 34

Describe a flexion tear-drop fracture

Back 34

avulsed anterior/inferior triangular shaped fragment which is displaced anteriorly

Front 35

Besides a vertically comminuted fracture of the vetebral body and sometimes a flexion tear drop fracture what else occurs to burst fractues of C3-C7

Back 35

facet joints and interspionous distance widened

Front 36

What percent of pt with burst fractures of C3-C7 have neurologic deficits

Back 36

70%

Front 37

What is the interspinous distance

Back 37

the distance between the posterior spinous process on lateral films

Front 38

Do burst fractures result in disc space narrowing

Back 38

yes

Front 39

What is the mechanism of a simple compression fracture of the C-spine

Back 39

flexion type injury

Front 40

Does anterior wedging of 3mm or more suggest a compression fracture

Back 40

yes

Front 41

Which endplate is usually invoved in a compression fracture

Back 41

superior endplate

Front 42

What is a clay-shovelers fracture

Back 42

avulsion fracture of spinous process of C6 or C7

Front 43

Which cervical level is more common for a clay-shovlers fracture

Back 43

C7

Front 44

What is the mechanism of a clay-shovelers fracture

Back 44

rotation of trunk relative to the neck

Front 45

Which direction to the inferior facets of the cervical vertebrae face

Back 45

they face posteriorly while the superior facets face anteriorly

Front 46

What is the mechanism by which a ligamentous injury to the spinal cord occurs

Back 46

flexion/distraction

Front 47

How does a distraction injury occur

Back 47

if your head gets stuck and body is being pulled away

Front 48

What is the opposite of a distraction injury

Back 48

compression/axial loading

Front 49

What are the findings on lateral plain film in a pt with a ligamentous injury of the C-spine

Back 49

disk space is narrower anteriorly

Front 50

Is there widening of the interspinous distance on lateral film in a ligamentous injury

Back 50

yes sometimes

Front 51

Can a ligamentous injury result in widening of a facet joint

Back 51

yes, typically this occur more posteriory (on lateral film)

Front 52

What are 2 potential complications of ligamentous injuries

Back 52

subluxation of the vetebral body or perched/locked facets

Front 53

What is more posteriorly located; superior or inferior facet

Back 53

inferior is more posterior

Front 54

What is the mechanism of a unilateral locked facet

Back 54

flexion/distraction/rotation

Front 55

What percent of unilateral locked facets result in a neurologic deficit

Back 55

30%

Front 56

What is seen on the lateral view in a pt with unilateral locked facets

Back 56

some vetebral bodies appear true lateral and other appear oblique

Front 57

What is the bowtie sign

Back 57

this is when some bodies appear lateral and some appear appear oblique in unilateral locked facets

Front 58

What will be seen on frontal film in a pt with unilateral locked facets

Back 58

the posterior spinous process will not line up

Front 59

On the lateral view what does the vetebrae with the unilateral locked facet look like

Back 59

t

Front 60

What is damaged in ligamentous injury of the cervical spine

Back 60

Posterior ligamentous structures involved in flexion injury are
(a) supraspinous ligament (b) interspinous ligament (c) facet joint capsule (d) posterior longitudinal ligament

Front 61

What percent of the vetbral body will be subluxed in bilateral locked facets

Back 61

at least 50%

Front 62

What is both bilateral and unilateral locked facets associated with

Back 62

a ligamentous injury

Front 63

What are the majore fractures of the cervical spine

Back 63

jeffersons
hangmans
extension teardrop
flexion teardrop
burst
clay shovelers
compression
perched/locked facets