L-Spine, Sacrum, and Coccyx Self Test Questions Flashcards
Compared with the spinous processes of the C- and T- spine, the lumbar spinous processes are:
larger and more blunt
The anterior/superior ridge of the upper sacrum is called the:
promontory
Each SI joint opens obliquely _____ degrees posteriorly
30
The angle of the midlumbar spine zygapophyseal joints in relation to the midsagittal plane is:
30-50°
Where is the pars interarticularis found?
between the superior and inferior articular processes
The Z joints of the lumbar spine are classified as _________, as joints with ______________ type of joint movement.
synovial; plane (gliding)
The ear and front leg of the Scottie dog make up the ______ joint, best seen in the oblique position.
Z
Which of the following topographic landmarks corresponds to the L2-L3 level?
xiphoid process
lower costal margin
iliac crest
ASIS
lower costal margin
It is possible to shield females for an AP projection of the sacrum or coccyx if the gonadal shields are correctly placed.
false
Why should the knees and hips be flexed for a recumbent AP projection of the lumbar spine?
reduces lumbar curvature (lordosis)
A lead mat or masking for lateral positions of the lumbar spine should not be used with digital imaging.
false
Anterior wedging and loss of vertebral body height are characteristic of:
compression fracture
Which of the following conditions is often diagnosed by prenatal ultrasound?
scoliosis
spina bifida
spondylolisthesis
spodylosis
spina bifida
Ankylosing spondylitis usually requires an increase in manual exposure factors.
false
Where is the CR centered for an AP projection of the lumbar spine with a 11- x 14-inch IR?
L3
Which set of Z joints of the lumbar spine is best demonstrated with an LAO position?
right
How much rotation of the spine is required to demonstrate the Z joint space between L1-L2?
50°
Describe the body build that might require CR angulation to open the intervertebral joint spaces with a lateral projection of the lumbar spine, even if the pt has some support under the waist.
pt w/ wider pelvis and narrow thorax
What type of CR angulation should be used for the lateral L5-S1 projection if the waist is not supported?
5-8° caudad
For the lateral L5-S1 projection the CR is parallel to the ___________ plane.
interiliac
Where is the CR centered for an AP axial projection for L5-S1?
A kVp of 90-100 can be used for a lateral L5-S1 projection when using a digital imaging system.
true
Which projection or method is designed to demonstrate the degree of scoliosis deformity between the primary and compensatory curves as part of a scoliosis study?
AP/PA series - Ferguson method
What projections are designed to measure mobility of the vertebral column at the site of a spinal fusion?
hyperextension/hyperflexion lateral
Where is the CR centered for an AP projection of the sacrum?
2 in. superior to pubic symphysis
What two things can be done to reduce the high amounts of scatter reaching the IR during a lateral projection of the sacrum and coccyx?
close collimation and lead mat
Why should a single lateral projection of the sacrum and coccyx be performed rather than the separate laterals of the sacrum and coccyx?
decrease gonadal dose
The pelvis must remain as stationary as possible when positioning for the hyperextension and hyperflexion projections.
true
A radiograph of an AP projection of the lumbar spine shows the SI joints are not equidistant from the spine. The right ala of the sacrum appears wider, and the right SI joint is more open than the left. Which specific positioning error is evident on this radiograph?
rotation to right
A radiograph of an LPO projection of the lumbar spine shows the downside pedicles are projected toward the posterior aspect of the vertebral bodies. What must be done to correct this error?
ensure no rotation of spine an be sure pt is at 45°
An AP projection of the sacrum shows that the sacrum is foreshortened and the foramina are not open. What positioning error may have led to this radiograph outcome?
CR alignment
A patient with a possible compression fracture of L3 enters the emergency room. Which projection(s) of the lumbar spine best demonstrate(s) the extent of this injury?
AP and lateral
A pt with a clinical history of spondylolisthesis of the L5-S1 region comes to the radiology dpt. What basic and special projections should be included in this study?
R and L oblique l-spine rotated 30°
AP lateral L5-S1
“spot”???????????????????????????
A study of the SI joints demonstrates that the joints are not open and the upper iliac wings are nearly superimposing the joints. The tech performed 35° RPO and LPO positions with a perp. CR. What can be done during the repeat exposure to open the joints?
ensure a 25-30° oblique of pt
