L/Sacrum/Coccyx

Question 1

An AP oblique lumbar projection (RPO or LPO position) with accurate positioning demonstrates all of the following except:

a. “Scotty dogs” that are stacked on top of one another.
b. the pedicles seen halfway between the midpoint and lateral border of the vertebral bodies.
c. the superior and inferior articular processes in profile.
d. the obturator foramina.

Answer 1

d. the obturator foramina.

Question 2

A left lateral sacral projection demonstrates the greater sciatic notches without superimposition and the superiorly situated femoral head anteriorly. How should the positioning setup be adjusted for an optimal projection to be obtained?

a. Rotate the right side of the pelvis posteriorly.
b. Position a radiolucent sponge between the lateral body surface and the imaging table to eliminate lumbar sagging.
c. Rotate the right side of the pelvis anteriorly.
d. Angle the central ray caudally.

Answer 2

c. Rotate the right side of the pelvis anteriorly.

Question 3

An AP lumbar projection obtained with the patient rotated toward the right side demonstrates:

1. the spinous processes positioned closer to the left pedicles.
2. the spinous processes positioned closer to the right pedicles.
3. smaller interpediculate space on the left side.
4. smaller interpediculate space on the right side.

Answer 3

1 and 3 only

Question 4

A lateral lumbar projection with accurate positioning demonstrates:

1. open intervertebral disk spaces.
2. the intervertebral foramina.
3. distorted vertebral bodies.
4. the zygapophyseal joints.

Answer 4

1 and 2 only

Question 5

An AP oblique lumbar projection (RPO or LPO position) obtained with the patient underrotated demonstrates:

1. obscured zygapophyseal joints.
2. the pedicles closer to the lateral surface of the vertebral bodies than the midline.
3. less lamina is seen.
4. the inferior and superior articular processes in profile.

Answer 5

1 and 2 only

Question 6

Examine the image below. What anatomy is labeled with the letter E?

a. L2 pedicle
b. L2 lamina
c. L3 lamina
d. L3 pedicle

Answer 6

d. The central ray was not angled enough.

Question 7

A left lateral lumbar projection with poor positioning demonstrates rotation. The posterior ribs that are most magnified and projected inferiorly are rotated anteriorly. How should the patient be repositioned for an optimal projection to be obtained?

a. Position the vertebral column parallel with the imaging table.
b. Rotate the patient’s right side posteriorly.
c. Angle the central ray caudally.
d. Rotate the patient’s left side posteriorly.

Answer 7

b. Rotate the patient’s right side posteriorly.

Question 8

An AP lumbar projection with poor positioning that demonstrates closed intervertebral disk spaces

1. also demonstrates distorted vertebral bodies.
2. was obtained with the patient rotated.
3. was obtained with the patient’s legs extended.
4. also demonstrates the sacrum and coccyx rotated toward the left side.

Answer 8

1 and 3 only

Question 9

An AP axial sacral projection with accurate positioning demonstrates:

1. the long axis of the median crest aligned with the pubic symphysis.
2. foreshortening of the first through fifth sacral segments.
3. the median sacral crest positioned closer to the right side.
4. the ischial spines equally demonstrated and aligned with the pelvic brim.

Answer 9

1 and 4 only

Question 10

An AP axial sacral projection with poor positioning demonstrates that the symphysis pubis rotated toward the patient’s right side. How was the positioning setup mispositioned for such a projection to be obtained?

a. The patient was in an LPO position.
b. The patient’s legs were extended.
c. The patient was in an RPO position.
d. The central ray was angled too cephalically.

Answer 10

c. The patient was in an RPO position.

Question 11

A lateral sacral projection with accurate positioning demonstrates:

1. the long axis of the sacrum aligned with the long axis of the collimated field.
2. near-superimposition of the greater sciatic notches.
3. an open L5-S1 intervertebral disk space.
4. the median sacral crest in profile.

Answer 11

1, 2, 3, and 4

Question 12

An AP axial sacral projection obtained with a perpendicular central ray demonstrates:

a. an elongated sacrum.
b. a foreshortened sacrum.
c. the sacrum and symphysis pubis without alignment.
d. the symphysis pubis superimposed over the lower sacral segments.

Answer 12

b. a foreshortened sacrum.

Question 13

An AP lumbar projection with accurate positioning demonstrates
1. open intervertebral disk spaces.
2. the vertebral bodies without distortion.
3. the spinous processes aligned with the midline of the vertebral bodies.
4. the sacrum and coccyx aligned with the symphysis pubis.

Answer 13

1, 2, 3, and 4