Lumbar Spine

Question 1

Sometimes there appears to be 4 lumbar vertebrae, what is this called?

Answer 1

“sacralization” of L5

Question 2

Sometimes there appears to be 6 lumbar vertebrae, what is this called?

Answer 2

“lumbarization” of first sacral segment

Question 3

What are the 5 views of the lumbar spine?

Answer 3

1) Anteroposterior (AP)
2) Left oblique
3) Right oblique
4) Lateral
5) “Coned-down view” of lumbosacral joint

Question 4

At minimum which views must be taken to perform basic evalution of the lumbar spine?

Answer 4

AP and lateral view

Question 5

Why does the Coned-down Viewof L5 to S1 subject patients to highest dose of radiation of any standard-plain film view?

Answer 5

The x-rays must penetrate both sides of iliac bones in order to properly view this segment

Question 6

In an anteroposterior view of the lumbar spine, what do the vertebral bodies represent on the “totem pole”?

Answer 6

Bird’s head

Question 7

In an anteroposterior view of the lumbar spine, what do the pedicles represent on the “totem pole”?

Answer 7

Bird’s eyes

Question 8

In an anteroposterior view of the lumbar spine, what do the transverse processes represent on the “totem pole”?

Answer 8

Feathers from bird’s head

Question 9

What do the lamina and spinous processes form?

Answer 9

The bird’s beak

Question 10

Which vertebral structure can be assessed to evaluate rotation?

Answer 10

Pedicles

Question 11

Assessment of alignment in AP view relies upon what bony landmarks?

Answer 11

• The spinous processes should align vertically

- The lateral surfaces of the vertebral bodies should line up vertically

Question 12

If the spinous processes do not align vertically what is this an indication for?

Answer 12

Rotation at one or more segments

Question 13

If the lateral surfaces of the vertebral bodies do not align vertically what is this an indication for?

Answer 13

Unilateral compression fracture or osteoporotic collapse of portion of vertebral body

Question 14

“Double lamina” is a sign of what?

Answer 14

Ssevere spondylolisthesis caused by inferior displacement of L5 on S1 when viewed in AP plane

Question 15

Why do the laminae in “double lamina” sign appear so close to one another?

Answer 15

Because L5 has slid anteriorly and inferiorly on S1

Question 16

Oblique views are taken with patient supine and shoulders and lower spine and pelvis rotated ____ side to be imaged

Answer 16

toward

Left oblique with left side rotated
Right oblique with right side rotated

Question 17

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s eye?

Answer 17

Pedicles

Question 18

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s ear?

Answer 18

Superior articular facet

Question 19

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s front leg?

Answer 19

Inferior articular facet

Question 20

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s tail?

Answer 20

Superior facet on opposite side

Question 21

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s back leg and back foot?

Answer 21

Spinous process

Inferior articular facet on opposite side

Question 22

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s muzzle?

Answer 22

Transverse processes

Question 23

In an oblique view of the lumbar spine, what is represented by the Scottie dog’s neck?

Answer 23

Pars interarticularis

Question 24

If the Scottie dog appears to be wearing a collar (lucency) what does this indicate?

Answer 24

fracture of pars interarticularis

Question 25

If there is a fracture of the pars interarticularis what is this diagnostic of?

Answer 25

spondylolysis

Question 26

At which vertebral level is spondylolysis most common?

Answer 26

L5

Question 27

How can you tell the difference between spondylolysis and spondylolisthesis?

Answer 27

Spondylolysis is represented by a Scottie dog with a collar | Spondylolisthesis is represented by a decapitated Scottie dog

Question 28

Spondylolysis vs. spondylolisthesis

Answer 28

Spondylolysis occurs when there is a fracture of the pars portion of the vertebra. Spondylolisthesis occurs when the vertebra shifts forward due to instability from the pars defect

Question 29

``` Spondylolisthesis Grades: Grade 1 = __% displacement Grade 2 = __% displacement Grade 3 = __% displacement Grade 4 > __% displacement ```

Answer 29

25 50 75 >75

Question 30

What is retrolisthesis?

Answer 30

Occurs when a superior vertebral body is displaced posteriorly to the vertebrae directly inferior to it

Question 31

Describe the cone-down view

Answer 31

It is a lateral view of the L5-S1 joint with x-ray energy so high that iliac crests become invisible

Question 32

Which vertebral bodies are visible in a coned-down view?

Answer 32

Lumbar and sacral bodies

Question 33

Is the interspace greater between L4- L5 or L5-S1?

Answer 33

L4-L5

Question 34

What is the Vacuum Phenomenon?

Answer 34

It is an accumulation of gas, principally nitrogen, in crevices within the intervertebral disk or vertebra produced by surrounding soft tissues

Question 35

In synovial joints the vacuum phenomenon is related to what?

Answer 35

The distraction of articular surfaces

Question 36

In intervertebral discs the vacuum phenomenon is related to what?

Answer 36

Degenerative processes most of the time. Rare cases of tumors and infections.

Question 37

When assessing alignment in the cone-down view what are you looking for?

Answer 37

Making sure that the inferior portion of L5 body is aligned with superior body of S1

Question 38

Dimensions in superior-inferior and anteroposterior planes should be how large?

Answer 38

approximately equal

Question 39

Can you assess soft tissue in a cone-down view? Why or why not?

Answer 39

No. | Soft tissue not visible as result of high dosage of radiation, which renders soft tissue invisible

Question 40

What may the absence of space between two vertebral bodies represent?

Answer 40

- A herniation of the nucleus pulposis | - Failure of embryonic segmentation at one or multiple levels

Question 41

What are the 3 types of congenital vertebral anomalies?

Answer 41

1) block vertebrae 2) hemivertebrae 3) transitional vertebrae

Question 42

Describe block vertebrae

Answer 42

are wedge-shaped vertebrae that can cause an angle in the spine (such as kyphosis, scoliosis, and lordosis

Question 43

Describe hemivertebrae

Answer 43

Occur when adjacent vertebrae fuse through their intervertebral discs due to improper segmentation

Question 44

Describe transitional vertebrae

Answer 44

Occur when the particular vertebrae take on the characteristics of another. For example the transverse process of the last cervical vertebra may resemble a rib

Question 45

What is Spondylosis Deformans?

Answer 45

The degeneration of IVDs that is characterized by the formation of bony spurs called Sharpey's fibers