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Let's look at this patient who suffered a hyperflexion injury.

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When I look at the cervical spine,

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I usually start with the sagittal reconstruction

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of the axial scans.

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And this is because identifying the malalignment and the

0:20

potential compromise of the spinal canal is very important.

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And I might get on the phone with the clinician almost immediately

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if I see the gross offset of the cervical spine.

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So looking at this sagittal scan,

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I'm already on the phone saying, all right, well,

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this is grade two anterolisthesis of C5 with respect to C6.

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Again,

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using the standard nomenclature for spondylolisthesis,

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where one-fourth is grade one,

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one fourth to two-fourths vertebral body

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offset is grade two. One-half to three

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fourths offset is grade three.

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And greater than three fourths offset is grade four.

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So in this case,

0:59

it's greater than one fourth of the vertebral body is offset.

1:03

So, this is likely going to be an unstable fracture.

1:06

As we move off of the midline,

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we come and we see that once again,

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the superior facet of the

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C6 vertebra is posterior to the inferior facet of the C5

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vertebra. This is abnormal. We see that on the normal side,

1:25

the superior facet is anterior to the inferior facet.

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Anterior to the inferior facet, anterior to the inferior facet.

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So this is a jumped facet,

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and you can see that it is associated with a fracture.

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And as we go off to the contralateral side,

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we see that this is a bilateral facet fracture-dislocation.

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In fact, this one's even more offset.

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And in addition to that,

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we have a fracture of the spinous process.

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Now, when it's at the C7 level,

2:01

we call this a clay shoveler's fracture.

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This is at the C5 level,

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and therefore we just call it the spinous process fracture.

2:10

So this is like an unstable injury,

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and let's look at it on the axial scan.

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So I've looked at this sagittal scan,

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I then will go to the thick section axial scans

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in bone and soft tissue windows.

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So, when we're scrolling through here from the C2 level going

2:28

downward, we come across the level of the fracture.

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And this is the displaced dislocated facet.

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And some people have called this the hamburger sign,

2:41

with the facet being displaced and dislocated posteriorly here.

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And it's convex outward on both sides.

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That is, facets are seen to convex outward opposed to each other.

2:58

This will often compromised the neural foramina.

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So if we go off to the neural foramina,

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we don't see that compromised so much on the one side,

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but on the other side,

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we do see that facet encroaching on the neural foramen.

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In addition,

3:12

this patient has the fracture fragment

3:15

on the vertebral body that you saw here.

3:18

And we also saw the spinous process fracture.

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This is in addition to the lamina

3:23

fracture on the left side.

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So this portion of the spine's process has been avulsed

3:29

from the normal position of the spinous process.

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And just as the clay shoveler's fracture

3:34

is a hyperflexion avulsion injury,

3:37

this is likely to be an avulsion injury as well.

3:40

After I've looked at the thick section bones,

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I will then look at the thick section soft tissue windows.

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The thick section soft tissue windows have better signal

3:51

to noise than the thin section soft tissue windows.

3:54

And what I'm looking for here is the presence of epidural

3:58

hematoma or cord injury or potentially

4:01

even cord hemorrhage,

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as well as the incidental findings of head neck masses or

4:09

calcification of the carotid arteries or any

4:12

of the cysts that can occur in the neck.

4:14

So although this is an unstable fracture and quite severe,

4:18

we do not see compromise of the spinal canal,

4:21

at least on the CT scan.

4:24

This is a cervical spine MRI scan of an individual

4:28

who had a cervical spine fracture.

4:30

We're looking at the T2-weighted scan and the STIR image.

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One of the things that should strike you on this case is that

4:38

there is bright signal intensity that's going through the C5

4:41

C6 disc. That is not normal and that's not degenerative.

4:46

That is actually traumatic injury to the disc.

4:50

Not only that,

4:50

but you see that the anterior longitudinal ligament is

4:55

disrupted with this bright signal intensity right at

4:59

that disc level. So this is single-column disease.

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Remember, we have the anterior half of the vertebra and the

5:06

interior longitudinal ligament is one column.

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But this bright signal going across the disc extends past the

5:14

midpoint of the vertebral body into the posterior portion.

5:18

That's the second column injury.

5:22

Not only that,

5:23

but we see this lifted up posterior longitudinal ligament

5:27

here's our posterior longitudinal ligament,

5:29

and then it's lifted up and it's discontinuous

5:31

across the back of C5.

5:34

Another portion of the second column

5:38

injury in this individual.

5:41

As we proceed posteriorly,

5:45

we notice that there is a discontinuity in this

5:48

black line, the so called spinolaminar line,

5:51

and that represents injury to the ligamentum flavum.

5:55

So this is the third column.

5:58

First column, anterior longitudinal

6:00

ligament and the anterior half of the vertebra. Second column,

6:04

posterior half of the vertebra and the spinal,

6:06

the posterior longitudinal ligament.

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And here we have the ligamentum flavum as well as the

6:11

interspinous ligaments, which are showing high signal intensity.

6:15

As you can see, there's absence of good visualization of the

6:19

normal bone of the spinous process.

6:22

And this patient does have a spinous process fracture.

6:25

As we go off to the off-midline,

6:29

we can see the normal articulation

6:31

of the facet joints on the one side.

6:34

And then as we go to the contralateral side, again,

6:38

although there is high signal intensity in the joint,

6:41

the facet joint of the superior facet is anterior to the

6:45

inferior facet. Lots of bright signal intensity in the muscle.

6:49

And this is confirmed on the sagittal T2.

6:54

We look at the sagittal T1 as well, obviously.

6:56

And the sagittal T1 is also useful from the standpoint of

7:01

demonstrating any hematoma. Because often the

7:03

hematoma is bright in the epidural space,

7:06

on the sagittal T1-weighted scan.

7:09

The cord looks fine and there does not appear

7:12

to be an epidural hematoma.

7:14

Now, this,

7:15

by virtue of the three columns involved, is an unstable spine.

7:20

And in point of fact, the shocking fact is that

7:27

that CT scan which showed grade 2 anterolisthesis of C5

7:35

on C6, is the exact same patient as this patient.

7:39

So that instability of the spine was manifested by the anterior

7:44

displacement subsequently of C5 on C6,

7:48

which potentially could injure the spinal cord by that offset.

7:55

So this was the preceding MRI scan showing the ligamentous

8:00

disruption and then subsequently, the patient dislocated

8:04

the facets and the vertebral body anteriorly.