Bontrager Chapter 9: L-Spine, Sacrum, Coccyx

what is the recommended kV range for lateral hyperflexion and hyperextension positions of the spine for a digital imaging system a. 70 to 75 b. 80 to 85 c. 85-95 d. 95 to 100

95 to 100

the superior and inferior vertebral notches join together to form the

intervertebral foramina

where is the central ray centered for a lateral L5-S1 projection of the lumbar spine

1 1/2 inch inferior to the iliac crest and 2 inches posterior to the ASIS

where is the CR centered for an oblique projection of the SI joints

1 inch medial from upside of ASIS

How much is the CR angled for the AP axial coccyx projection?

10 degrees caudad

how much CR angulation is required for an AP projection of the sacrum for a typical male patient

15 degrees cephalad

where is the CR centered for an AP axial projection of the sacrum

2 inches superior to the pubic symphysis

where is the central ray centered for an AP projection of the coccyx

2 inches superior to the symphysis pubis

how much rotation of the body is required for oblique positions of the SI joints

25 to 30 degrees

for the ferguson method, the elevated foot must be raised a minimum of ___ inches

3 to 4

the SI joints lie at an oblique angle of ___ degrees from the coronal plane

30

how much rotation is required to visualize the zygapophyseal joints properly at the L5-S1 level

30 degrees

What amount and direction of central ray angulation is required for an AP axial L5-S1 projection on a male patient?

30 degrees cephalad

what type of CR angle is recommended for the AP axial projection of the SI joints on a female patient a. 20 degrees cephalad b. 30 degrees cephalad c. 30 degrees caudad d. 35 degrees cephalad

35 degrees cephalad

a patient with a wide pelvis and narrow thorax may require a central ray angle of ___ degrees ____ (caudad or cephalad) for a lateral position of the lumbar spine

5-8 degrees caudad

would the degree of angle to demonstrate the zygapophyseal joints be greater or lesser for the lower lumbar vertebrae as compared with the upper?

50 degrees for upper and 30 degrees for lower to midsagital plane

which two structures can be evaluated to determine whether rotation os present on a radiograph of an AP projection of the L-spine A: B:

A: SI joints are equidistant from the spine B: spinous process should be midline to the vertebral column

patients should be asked to empty the urinary bladder before performing which projections of the vertebral column

AP of sacrum and coccyx

match each of the following topographic landmarks to the correct vertebral level ASIS Xiphoid Process Lower Costal Margin Iliac crest Symphysis Pubis

ASIS: S1-S2 Xiphoid Process: T9-T10 Lower Costal Margin: L2-L3 Iliac Crest: L4-L5 Symphysis Pubis: prominence of greater trochanter

select the imaging modality that best demonstrates each of the following pathologic features or conditions compression fractures of the L-spine

CT

List the specific joints or foramina that are demonstrated with the following lumbar spine positions: LPO: RAO: Lateral: RPO: LAO:

LPO: left zygapophyseal RAO: left zygapophyseal Lateral: intervertebral foramina RPO: right zygapophyseal LAO: right zygapophyseal

select the imaging modality that best demonstrates each of the following pathologic features or conditions soft tissues of L-spine

MRI

select the imaging modality that best demonstrates each of the following pathologic features or conditions structures w/i subarachnoid space

MRI and myelography

the degree of obliquity required for an oblique projection at T12-L1 level is approximately ____ degrees, whereas L5-S1 spine level requires a _____ oblique. Therefore, a ____ oblique is performed for the general lumbar spine

T12-L1 - 50 degrees L5-S1 - 30 degrees general - 45 degrees

if a patient cannot lie on his back for the AP sacrum because it is too painful, what alternate projection can be taken to achieve a similar view of the sacrum

a PA prone w/ 15 degree caudad CR angle

match each of the following clinical indications to the correct definition or statement inflammatory condition that is most common in males in their 30s

ankylosing spondylitis

what is the name of the superior broad aspect of the coccyx

base

select the imaging modality that best demonstrates each of the following pathologic features or conditions Osteoporosis

bone densitometry

list the structure classification and movement classification and type of the intervertebral joints

cartilaginous with amphiarthroidal (no) movement

match each of the following clinical indications to the correct definition or statement fracture of the vertebral body caused by hyperflexion force

chance fracture

what is the formal term for the tailbone

coccyx

which of the following techniques or devices produces more uniform density along the vertebral column for an AP/PA scoliosis projection a. use of a 14x36 in IR b. lower kV c. higher mAs d. compensating filter

compensating filter

match each of the following clinical indications to the correct definition or statement a type of fracture that rarely causes neurologic deficits

compression fracture

Which side of the spine should be elevated for the second exposure for the AP/PA projection (ferguson) scoliosis series (by having patient stand on a block with one foot)

convex side

what is another term for the sacral horns

cornua

which positioning error has been committed if the structures described in the previous question are projected too far posterior with a 45 degree oblique position of the L-spine

excessive rotation

T/F - The AP projections of the sacrum and coccyx can be taken as one single projection to decrease gonadal dose.

false

T/F - The knees and hips should be extended for an AP lumbar spine.

false

T/F: gonadal shielding should always be used for male and female patients for studies of the lumbar spine, sacrum, and coccyx

false

T/F: the AP projection of the lumbar spine opens the intervertebral joint spaces better than the PA projection

false

T/F: the lead blocker mat and close collimation must not be used when performing digital imaging of the lumbar spine

false

T/F: the lower margin of the cassette must include the symphysis pubis for a scoliosis series

false

T/F: the use of higher kV and lower mAs for lumbar spine radiography improves radiographic contrast but increases patient dose

false

match each of the following clinical indications to the correct definition or statement most common at the L4-L5 level and may result in Sciatica

herniated nucleus pulposus

which projection should be taken to evaluate flexibility following spinal fusion surgery

hyperflexion and hyperextension lateral

with a 14x17 IR, the CR is centered at the level of the ________ for an AP and lateral lumbar spine projections

iliac crest

which position or projection of the lumbar spine series best demonstrates a possible compression fracture

lateral

which radiographic position best demonstrates the intervertebral foramina

lateral position

Which SI joint is visualized with an RPO position?

left

select the imaging modality that best demonstrates each of the following pathologic features or conditions inflammatory conditions such as Paget's disease

nuclear medicine

A portion of the lamina located between the superior and inferior articular processes is called the

pars interarticularis

the ___, which is the eye of the "Scottie dog" should be near the center of the vertebral body on a correctly oblique lumbar spine position

pedicle

the small foramina found in the sacrum are called

pelvic sacral foramina

During the AP (PA) right and left bending projections of the lumbar spine, the _____ must remain stationary during positioning

pelvis

In addition to good collimation, what should be done to minimize overall "fogging" on a lateral lumbar spine or lateral sacrum and coccyx radiograph?

place lead blocker on tabletop behind patient

the anterior and superior aspect of the sacrum that forms the posterior wall of the pelvic inlet is called the

promontory

Why should the knees and hips be flexed for an AP lumbar spine projection?

reduces lumbar curvature, which opens intervertebral disk spaces

which specific set of zygapophyseal joints is demonstrated with an LAO position

right (upside)

match each of the following clinical indications to the correct definition or statement lateral curvature of the vertebral column

scoliosis

match each of the following clinical indications to the correct definition or statement congenital defect in which the posterior elements of the vertebrae fail to unite

spina bifida

match each of the following clinical indications to the correct definition or statement forward displacement of one vertebra onto another vertebra

spondylolisthesis

match each of the following clinical indications to the correct definition or statement dissolution and separation of the pars interarticularis

spondylolysis

list the structure classification and movement classification and type of the zygapophyseal joints

synovial with diarthroidal plane or gliding movement

T/F - PA or AP projection for a scoliosis series frequently includes one erect and one recumbent position for comparison.

true

T/F - The female ovarian dose used for a PA lumbar spine is approx 30% less than the the dose used for an AP projection.

true

T/F: a PA projection for an scoliosis series requires only about one tenth the dose to the breasts as compared to the AP projection, even if properly collimated

true

T/F: placing a lead blocker mat behind the patient for lateral lumbar spine positions improves image quality

true

t/f an increased SID of 44 to 46 inches reduces magnification of the spine anatomy

true

How should the spine of a patient with scoliosis be positioned for a lateral position of the lumbar spine?

with the sag or convexity of the spine closest to the IR