Chapter 9 Exam (Lumbar Spine, Sacrum, & Coccyx)
Which of the following represents correct evaluation for an AP lumbosacral spine radiograph? 1. The pedicles are equidistant to the spinous processes 2. Spinous processes are centered to the vertebral bodies 3. The vertebral laminae are superimposed
1 and 2
Which of the following structures is/are part of the sacrum? 1. Promontory 2. Transverse foramina 3. Auricular surface
1 and 3
Which of the following would be benefits of flexing the knees when performing an AP lumbosacral spine x-ray? 1. Flexing the knees straightens the curve of the spine and places it closer to the image receptor (IR) 2. Flexing the knees results in more consistent brightness levels across the length of the spine 3. Flexing the knees makes the patient more comfortable reducing the chance of motion
1 and 3
LPO and RPO SI joint CR
1 inch medial to upside ASIS
Which of the following is/are appropriate evaluation criteria for an AP projection of the sacrum? 1. Sacrum free of superimposition by the pubic symphysis 2. Open L5/S1 joint space 3. Superimposition of the sciatic notches
1 only
For the lateral projection of the L5-S1 joint, the central ray is directed
1-1 1/2 inches inferior to the iliac crest and 2 inches posterior to the ASIS
A young female patient comes to the radiology department for a scoliosis series. She has had repeated radiation exposure throughout a period of time and is understandably concerned about the radiation. What three things can the technologist do to minimize the dose delivered to the patient's breasts?
1. use high kV 2. perform PA 3. use breast shield
Lateral L5-S1 lumbar spine CR
1.5 inches inferior to crest and 2 inches posterior to ASIS
Where is the central ray centered for an AP axial projection for L5-S1?
1.5 inches inferior to iliac crest & 2 inches posterior to ASIS
CR angulation for AP axial coccyx
10 degree caudad
What is the appropriate central ray angulation and entrance point for an AP axial projection of the coccyx?
10 degrees caudad entering midsagittal plane at a level 2 inches superior to the pubic symphysis
CR angulation for AP axial sacrum
15 degrees cephalad
In order to minimize distortion of the sacrum in frontal projections, which of the following is the most correct angulation of the central ray?
15 degrees cephalad
The ASIS is approximately at the same level as the
1st or 2nd sacral segment
Which of the following is/are appropriate evaluation criteria for a lateral projection of the sacrum? 1. Symmetrical sacral foramina 2. Greater sciatic notches are superimposed 3. Superimposition of the femoral heads
2 and 3
AP Axial sacroiliac joints CR
2 inches below level of ASIS
Where should the central ray enter for a RPO of the lumbosacral spine?
2 inches medial to the left ASIS and 1.5 inches superior to the level of the iliac crest
AP axial sacrum & coccyx CR
2 inches superior to pubis symphysis
Where is the central ray centered for an AP projection of the sacrum?
2 inches superior to symphasis pubis
When performing an AP axial projection of the sacrum, the central enters at the MSP and
2 inches superior to the pubic symphysis
How much are SI joints obliqued?
25 degrees
SI joints are done at which degree during which projection?
25-30 degree obliques
Lateral coccyx CR
3-4 inches posterior and 2 inches distal to ASIS
Lateral sacrum and coccyx CR
3-4 inches posterior to ASIS
A patient presents in the emergency department with severe pain in the inferior spine after falling on the ice. A coccyx examination is ordered. When performing the lateral projection of the series, what is the appropriate central ray entrance point?
3.5 inches posterior and 2 inches inferior to the ASIS
CR angulation for AP axial L5-S1 lumbar spine
30 degrees for male patients 35 degrees for female patients
CR angulation AP axial SI joints
30 degrees for males 35 degrees for females
The zygopophyseal joints are situated how many degrees in relation to the midsaggital plane?
30-50 degrees
How many segments does an adult coccyx posses?
4
What projection best demonstrates the zygapophyseal joints?
45 degree obliques
The angle of the midlumbar spine zygopophyseal joints in relation to the midsaggital plane is
45 degrees
When performing a RPO lumbar spine radiograph, the body should be rotated so that the mid-sagittal plane forms what degree of angulation with the image receptor?
45 degrees
In an infant, the sacrum is normally composed of how many segments?
5
CR angulation for lateral L5-S1 lumbar spine
5-8 degrees caudad
What type of central ray angulation should be used for the lateral L5-S1 projection if the waist is not supported?
5-8 degrees caudad
What is the correct central ray orientation for a localized lateral of the L5/S1 vertebrae?
5-8° caudad
How much rotation of the spine is required to demonstrate the zygapophyseal joint space between L1-L2?
50 degrees plane of table
Where are the intervertebral foramen situated in relation to the midsagittal plane?
90 degrees
When performing a lateral lumbar spine on a patient with a wide pelvis and a narrow waist, which of the following should be done?
A sponge should be placed under the waist to ensure the entire spine is parallel to the image receptor
A patient comes to the radiology department for a follow-up study for a compression fracture of L3. The radiologist requests that collimated projections be taken of L3. Which specific projections and centering would provide a quality study of L3 and the intervertebral joint spaces?
AP or PA with collimation to lateral projection & CR 2 inches above the iliac crest
A patient with a clinical history of spondylolisthesis of the L5-S1 region comes to the radiology department. What basic and special projections should be included in this study?
AP, lateral, L5-S1 spot lateral, & right and left oblique positions
The outer portion of an intervertebral disk is
Annulus fibrosus
A positioning series for SI joints is performed on a patient. The resultant radiographs do not demonstrate the inferior portion of the joints. What can be done during the repeat exposure to demonstrate this aspect of the SI joint?
CR angled 15-20 degrees cephalad
An AP projection of the coccyx demonstrates the coccyx superimposed by the superior rami of the pubic bones. What correction, if any, should be made?
Increase the caudal angulation of the tube
Why is the lateral lumbar spine radiograph taken with the patient holding the breath in expiration?
It reduces the superimposition of the costophrenic angles and the first lumbar vertebra
Lower costal margin is at the level of
L2-L3
Which lumbar vertebrae is the largest?
L5
AP/PA & LATERAL lumbar spine CR
Large IR: iliac crest (L4-L5) Small IR: level of L3
A patient comes to the radiology department with a clinical history of HNP. Which imaging modality provides the most diagnostic study for this condition?
MRI
Which modality demonstrates the spinal cord better? MRI or CT?
MRI
When evaluating an AP axial projection of the coccyx, the technologist notices that the obturator foramina are symmetrical, and that the coccyx is just superior to and in the same plane as the pubic symphysis and is superimposed by the bladder. What positioning error, if any, has been made with this image?
No mistake has been made
A patient with an injury to the coccyx enters the emergency room. When attempting the AP projection, the patient complains that it is too uncomfortable to lie on his back. He is unable to stand. What other options are available to complete the study?
PA & reverse the CR angle to cephalad
When radiographing the lumbar spine in the oblique position, the vertebral anatomy resembles a "Scottie dog."The eye of the Scottie dog represents which of the following?
Pedicle
Which of the following bony landmarks lies at the same level as the superior border of the pubic symphysis?
Prominence of the greater trochanter
Which of the following conditions would be indicated by the appearance of a collar on the Scottie dog on an oblique lumbar spine radiograph?
Spondylolysis
Routine frontal lumbar spine images are typically performed with the patient in which position?
Supine on table with knees flexed
The sacroiliac joints are classified as which of the following?
Synovial, gliding
Xiphoid tip is at the level of
T9-T10
Which of the following statements is true regarding positioning for a lateral lumbar spine?
The central ray enters at the midcoronal plane
T/F A kV range of 90-100 kV can be used for a lateral L5-S1 projection when using a digital imaging system.
True
T/F The pelvis must remain as stationary as possible when positioning for the hyperextension and hyperflexion projections.
True
Scoliosis
abnormal lateral curvature of the spine
How to reduce scatter
add lead shield behind the back of the patient
Distal pointed tip of coccyx is called?
apex
broader superior portion of coccyx is called?
base
Pediatric Scoliosis studies taken AP reduce what two things by 90%?
beast and thyroid dose
Intervertebral joints are classified as
cartilaginous and amphiarthrodial
What part of the lumbar vertebrae are common sites for injury and pathologic processes?
cartilaginous disks
A study of the sacroiliac joints demonstrates that the joints are not open and the upper iliac wings are nearly superimposing the joints. The technologist performed 35-degree RPO and LPO positions with a perpendicular CR. What can be done during the repeat exposure to open the joint?
decrease rotation of body for oblique positions with CR centered to the upside SI joints
A radiograph of an oblique position of the lumbar spine shows that the downside pedicle and zygapophyseal joint are posterior in relation to the vertebral body. What modification of the position must be made during the repeat exposure to produce a more diagnostic image?
decrease rotation of the spine & body
A radiograph of an LPO projection of the lumbar spine shows that the downside pedicles are projected toward the posterior aspect of the vertebral bodies. What must be done to correct this error during the repeat exposure?
decrease rotation or obliquity of the spine
What kind of joints do the LPO/RPO projections of the L-spine demonstrate?
down side joints
Posterior projections deals with __ joints
downside
What should the Pediatric scoliosis projections include?
entire L and T spines
Kyphosis
excessive outward curvature of the spine, causing hunching of the back (humpback)
Is a male or female more likely to experience a fracture of the coccyx?
female because of the shape and more vertical orientation of the coccyx
What are the largest individual vertebrae?
five lumbar vertebrae
For female patients, what is not always used during lumbar spine projections?
gonadal shielding
Which projections are taken for functional studies?
hyperextension and hyperflexion
A patient comes to the radiology department for a lumbar spine study following spinal fusion surgery. Her surgeon wants a study to assess mobility of the spine at the fusion site. Which radiographic positions provide this information?
hyperflexion & hyperextension lateral positions
Chance Fracture
hyperflexion force that causes fracture through the vertebral body and posterior elements
A radiograph of a lateral projection of a female lumbar spine shows that the mid to lower intervertebral joint spaces are not open. The technologist supported the midsection of the spine with sponges to straighten the spine. What else can be done to open the joint spaces during the repeat exposure?
if its a wide pelvis angle CR 5-8 degrees caudad
A radiograph of an AP axial projection of the coccyx shows that the distal tip is superimposed over the symphysis pubis. What must the technologist do to eliminate this problem during the repeat exposure?
increase in CR angle
A radiograph of a lateral L5-S1 projection shows that the joint space is not open. The technologist did support the middle aspect of the spine with a sponge. What else can the technologist do to open the joints space during the repeat exposure?
increase in CR angle (5-8 degrees caudad) OR place addition support under spine
Leg of the Scottie Dog
inferior articular process
Ankylosing spondylitis
inflammatory condition that usually begins in the SI joints and progresses up the vertebral column; spine may become completely rigid MOST COMMON IN MEN IN THEIR 30s
An AP projection of the sacrum reveals that the sacrum is foreshortened and the foramina are not open. What positioning error may have led to this radiographic outcome?
insufficient cephalad CR angle or CR angled in the wrong direction
A radiograph of an LPO projection of the lumbar spine shows that the downside pedicles and zygopophyseal joints are projected over the anterior portion of the vertebral bodies. Which specific positioning error is present on this radiograph?
insufficient rotation of the spine
Most superior portion of the iliac crest is at the same level as the
junction of the 4th and 5th lumbar vertebrae
The intervertebral foramina are best demonstrated during which projection?
lateral
A patient with a clinical history of spondylolisthesis at the L5-S1 level comes to the radiology department. Which specific lumbar spine position is most diagnostic in demonstrating the extent of this condition?
lateral L5-S1 position
A patient with a possible compression fracture of L3 enters the emergency room. Which projection(s) of the lumbar spine best demonstrates the extent of this injury?
lateral projection (may include coned-down spot AP/PA)
Where is the central ray centered for an AP projection of the lumbar spine?
level of L3
AP axial L5-S1 lumbar spine CR
level of the ASIS
Which of the topographic landmarks corresponds to the L2-L3 level?
lower costal margin
The coccyx is what portion of the vertebral column?
most distal
How much does the SI joint open?
obliquely posteriorly at an angle of 30 degrees
On the L5-S1 projection, where should the CR be
parallel to the interiliac line
Neck of the Scottie Dog
pars interarticularis
Eye of the Scottie Dog
pedicle
A patient comes to the radiology department for a lumbar spine series. She has a clinical history of severe kyphosis. How should the lumbar spine series be modified for this patient?
performed ERECT
A patient comes to the radiology department for a lumbar spine series. He has a clinical history of advanced spondylolysis. Which specific projection(s) of the lumbar spine series will best demonstrate this condition?
posterior & anterior oblique
Which set of zygapophyseal joints of the lumbar spine is best demonstrated with an LAO position?
right (upside)
RAO & LAO lumbar spine CR
rotate body 45 degrees L3 at the level of the lower costal margin *1-2 inches above crest & 2 inches medial to ASIS
A radiograph of an AP projection of the lumbar spine shows that the spinous processes are not midline to the vertebral column and distortion of the vertebral bodies is present. Which specific positioning error is present on this radiograph?
rotation of the spine
A radiograph of an AP projection of the lumbar spine shows that the sacroiliac joints are not equidistant from the spine. The right ala of the sacrum appears wider, and the left SI joint is more open than the left. What specific positioning error is evident on this radiograph?
rotation to the patients right
What anatomy is inferior to the lumbar vertebrae?
sacrum
herniated nucleus pulposus (HNP)
slipped disk; trauma or improper lifting; soft inner part of the intervertebral disk protrudes through the fibrous outer layer pressing on the spinal cord or nerves
Ear of the Scottie Dog
superior articular process
Zygopophyseal joints are classified as what kind of joints with what kind of joint movement?
synovial & plane (gliding)
Zygopophyseal Joints are classified as what kind of joint?
synovial/diarthrodial
The coccyx is also known as the
tailbone
Nose of the Scottie Dog
transverse process
Anterior projections deals with __ joints
upside
Front leg of the above Scottie Dog and ear of the below Scottie Dog make the
zygapophyseal joint
The ear and front leg of the "Scottie dog" make up which joint?
zygopophyseal
