ARRT Spine and Pelvis Procedures 5 — Questions and Answers
Question 1: The Stener-Laurin axial projection is used to evaluate which spinal region?
- Cervical spine flexion/extension
- Lumbosacral junction (L5-S1) (Correct answer)
- Coccyx
- Thoracic spine in scoliosis
Correct answer: Lumbosacral junction (L5-S1)
The axial (angled AP) projection of the lumbosacral junction projects the L5-S1 intervertebral disc space open to evaluate the joint.
Question 2: In the lateral decubitus position for a cervical spine trauma series, what is the purpose of applying gentle traction to the patient's arms?
- To reduce fracture displacement
- To depress the shoulders and visualize C7 (Correct answer)
- To straighten the cervical lordosis
- To immobilize the patient
Correct answer: To depress the shoulders and visualize C7
Gentle downward traction on the arms depresses the shoulders inferiorly, allowing visualization of the C7 vertebra on the lateral cervical projection.
Question 3: Flexion and extension lateral projections of the cervical spine are primarily used to evaluate:
- Disc herniation
- Ligamentous stability and atlantoaxial instability (Correct answer)
- Neural foramina patency
- Vertebral body fractures
Correct answer: Ligamentous stability and atlantoaxial instability
Flexion and extension lateral projections stress the cervical ligaments and reveal instability or hypermobility that is not apparent on neutral lateral views.
Question 4: On a well-positioned AP thoracic spine radiograph, which structure should be demonstrated in the center of each vertebral body?
- Pedicle shadow
- Intervertebral foramen
- Spinous process (Correct answer)
- Transverse process
Correct answer: Spinous process
The spinous processes should project through the center of each vertebral body on a true AP thoracic spine, confirming no patient rotation.
Question 5: Which oblique body position places the LEFT zygapophyseal joints of the lumbar spine closest to the IR?
- Right posterior oblique (RPO)
- Left posterior oblique (LPO) (Correct answer)
- Right anterior oblique (RAO)
- Left anterior oblique (LAO)
Correct answer: Left posterior oblique (LPO)
In the LPO position, the left side is closest to the IR, demonstrating the LEFT zygapophyseal joints of the lumbar spine.
Question 6: The inlet projection of the pelvis is obtained with the patient supine and the CR directed:
- 40 degrees caudad (Correct answer)
- 40 degrees cephalad
- Perpendicular to the IR
- 15 degrees caudad
Correct answer: 40 degrees caudad
The pelvic inlet projection uses a 40-degree caudad CR angle to project down through the pelvic brim, demonstrating the true pelvic inlet shape.
Question 7: A radiograph of the lateral lumbar spine shows the intervertebral foramina are not open and the disc spaces are narrowed posteriorly. The most likely cause is:
- Insufficient CR cephalad angulation
- Patient rotation — not in true lateral (Correct answer)
- Excessive SID
- Incorrect collimation
Correct answer: Patient rotation — not in true lateral
Foramina that are not open and asymmetric disc spaces on a lateral lumbar projection indicate the patient was rotated from the true lateral position.
ARRT Spine and Pelvis Procedures 5
The Stener-Laurin axial projection is used to evaluate which spinal region?