Lumbar Spine Flashcards
How many Lumbar vertebrae are there?
5
Lamina lie ________ to the pedicles & transverse processes
Posterior
Intervertebral foramen are at __ degree angle to the MSP, they are demonstrated in the _________ projection
90, Lateral
Zygapophyseal joints may range from ____ to ____ degrees to the MSP
30 to 60
___ degree oblique demonstrates the majority of the z-joints
45
The area between the superior & inferior articulating process is the
pars interarticularis
The lumbar spine has a natural ___________ curvature
-Lordotic
*Concave posteriorly
*Convex anteriorly
Lumbar Spine Considerations
-Patient should empty bowels and bladder before exam if possible
-PA Projection
-PA projection can be used instead of the AP in order to reduce exposure to the gonads
-PA projection also aids in visualization of the disc spaces, as the angle of beam divergence mimics the angle of the spine from that direction
Why do we flex our knees for the AP Lordotic projection
because the natural lordotic curvature tends to distort the joint spaces in the AP projection
*You could also do a PA projection to help with this
AP Lumbar Spine Positioning
-14 X 17 Cassette LW in bucky
-Pt supine or upright
-SID of 48” may be used to reduce distortion of disc spaces
-If pt is supine, flex the knees and hips to place lower back in contact with the table
-CR perpendicular to MSP at the level of the iliac crests
-Collimate to the spine
-Shield if possible
-Suspend respiration at the end of full expiration
AP Lumbar Spine Evaluation Criteria
-Symmetric vertebrae, with spinous processes centered to the bodies
-Sacroiliac joints equidistance from the vertebral column
-Open intervertebral disc spaces
AP Lumbar Spine showing spina bifida
Lateral Lumbar Spine Positioning
-14 X 17 Cassette LW in bucky
-SID: 48 inches to reduce magnification
-Pt recumbent, lying on affected side
-May be performed upright
-If recumbent, have patient flex hips, knees, and elbows
-Pt in true lateral position with knees and hips superimposed
-May place a sponge or radiolucent pad under waist to alleviate lateral curvature on
patient’s with larger hips
-CR perpendicular to the MCP at the level of the iliac crests
-May need to angle the CR caudally 5 to 7 degrees if the spine is not completely horizontal
-Collimate
-Shield
-Suspend respiration at the end of full expiration
How is quality of Lateral projections enhanced?
Laying a strip of lead rubber on table posteriorly
Lateral Lumbar Spine Evaluation Criteria
-Profile image of the intervertebral foramina of L1-L4
-Open intervertebral disc spaces
-Superimposed iliac crests and posterior margins of the vertebral bodies
L5-S1 “Spot” Lumbar Spine Positioning
-SID: 40 inches
-10 X 12 Cassette LW in bucky
-Pt in lateral recumbent position laying ON AFFECTED SIDE
-Flex hips, knees, and elbows and place arms at right angles to the body
-Superimpose knees and hips, placing a support between knees if necessary for pt comfort
-If needed, place a radiolucent sponge under the waist to straighten the lumbar spine
-CR angled 5 to 7 degrees caudal to a point 2 inches posterior to the elevated ASIS and 1.5 inches inferior to the crest (may be perpendicular)
-Collimate
-Suspend respiration
What else can you do for the L5-S1 spot if you don’t use an angle
put sponge under the waist
L5-S1 “Spot” Lumbar Spine Evaluation Criteria
-Lateral projection of the lumbosacral junction, the lower one or two lumbar vertebrae, and upper sacrum
-Disc space between lumbar and sacral vertebra is open
-Crests of the ilia should be closely superimposed if beam is not angled
AP Oblique Lumbar Spine Positioning
-14 X 17 Cassette LW in bucky
-SID: 40 inches
-Pt either upright or supine
-Rotate the patient to a 45 degree oblique position
-CR perpendicular to 2 inches medial to the elevated ASIS and 1 to 1.5 inches above the iliac crests
-Collimate
-Shield
-Suspend respiration at end of full expiration
AP Oblique Lumbar Spine Evaluation Criteria
-Articular processes of the side closest to the IR
-Both sides are done for comparison
-When the patient is properly positioned, the vertebrae form the appearance of “Scottie Dogs”
-T12-L1 and L1-L2 intervertebral joint spaces open
T or F: Flexion and extension laterals are often added to a series when a patient has a history of surgical lumbar fusion or prior trauma
True
T or F: Lateral Flexion and Extension views should be performed in acute trauma settings
False, just trauma
Lateral: Flexion & Extension Lumbar Spine positioning
-14 X 17 Cassette LW in bucky
-SID: 48
-Pt upright or in lateral recumbent position using positioning criteria for lateral lumbar spine
-For the first radiograph, have the pt bend forward to flex the spine as much as possible
-For the second radiograph, have the patient bend backward to extend the spine as much as possible
-CR perpendicular to the spinal fusion area or L3
Lateral: Flexion & Extension Lumbar Spine Evaluation Criteria
-Hyperflexion and hyperextension to determine whether motion is present in the area of a spinal fusion, indicating a non-union, or to localize a herniated disk as shown by limitation of motion
-No rotation of vertebral column
-Hyperflexion or hyperextension identification markers placed on the film
