ARRT Spine and Pelvis Procedures 3 — Questions and Answers
Question 1: On an AP projection of the pelvis, proper rotation is confirmed when:
- Both iliac wings appear equal in size and the obturator foramina are symmetric (Correct answer)
- The greater trochanters are in profile
- The femoral necks are foreshortened
- The ischial spines are superimposed on the acetabula
Correct answer: Both iliac wings appear equal in size and the obturator foramina are symmetric
Symmetric iliac wings and equal obturator foramina indicate no rotation on an AP pelvis projection.
Question 2: The Towne method for the sacrum requires the patient to be supine with the CR directed:
- 30-40 degrees cephalad (Correct answer)
- 30-40 degrees caudad
- 15 degrees caudad
- Perpendicular to the IR
Correct answer: 30-40 degrees cephalad
For an AP axial (Towne-type) projection of the sacrum, the CR is angled 30-40 degrees cephalad to project the sacrum through the pelvis.
Question 3: Which projection is best suited to demonstrate a spondylolisthesis of the lumbar spine?
- AP projection
- Lateral projection (Correct answer)
- 45-degree oblique projection
- AP axial projection
Correct answer: Lateral projection
The lateral projection of the lumbar spine best demonstrates anterior or posterior displacement of one vertebra on another (spondylolisthesis).
Question 4: The acetabulum is best demonstrated with which projection?
- AP pelvis
- Judet method (anterior and posterior obliques) (Correct answer)
- Lateral hip
- Axiolateral (Danelius-Miller) method
Correct answer: Judet method (anterior and posterior obliques)
The Judet method uses 45-degree anterior and posterior oblique projections to demonstrate the anterior and posterior columns of the acetabulum.
Question 5: For the lateral projection of the lumbar spine, the patient's hips and knees should be:
- Extended fully
- Flexed slightly to reduce lordosis (Correct answer)
- Crossed at the ankles
- Abducted 45 degrees
Correct answer: Flexed slightly to reduce lordosis
Flexing the hips and knees flattens lumbar lordosis and places the long axis of the spine parallel to the IR for a true lateral.
Question 6: The standard AP projection of the thoracic spine uses which breathing technique to blur overlying ribs and lung markings?
- Suspended expiration
- Suspended inspiration
- Slow, shallow breathing during exposure (Correct answer)
- Valsalva maneuver
Correct answer: Slow, shallow breathing during exposure
Slow, shallow breathing during a long exposure (breathing technique) blurs overlying ribs and pulmonary vasculature on the AP thoracic spine.
Question 7: Which view demonstrates the neural foramina of the cervical spine?
- AP projection
- Lateral projection
- 45-degree oblique projection (Correct answer)
- Axial (Towne) projection
Correct answer: 45-degree oblique projection
A 45-degree oblique (anterior or posterior) projection of the cervical spine opens the intervertebral foramina on the side away from the IR for AP obliques.
ARRT Spine and Pelvis Procedures 3
On an AP projection of the pelvis, proper rotation is confirmed when: