Radiologic Eval of Lumbosacral Spine

Question 1

List radiologic views of the Lumbar spine that may be used during a routine exam

Answer 1

1. AP
2. Lateral
3. R/L Oblique
4. Coned lateral view L5-S1
5. Lateral view standing flexion and extension

Question 2

list radiologic views of the SIJ that may be used during a routine exam

Answer 2

1. AP axial
2. R/L Oblique view
3. Lateral view: coccyx

Question 3

what can be observed with a R/L Posterior Oblique projection at the Lumbar spine?

Answer 3

1. articulating process
2. Z-joints
3. Pars interarticularis
4. Scotty dog

Question 4

what can be seen with a coned lateral view of L5-S1?

Answer 4

1. can still observe 3 parallel lines of vertebral bodies
2. disc spaces preserved
3. lumbosacral angles
   
   1. Barge’s
   2. Ferguson’s

Question 5

what can be observed with an AP axial view of the SIJ?

Answer 5

1. Articular surfaces are superimposed
2. smooth osseous margins
3. symmetry of SIJs
4. L5/S1
5. Coccyx

Question 6

which view allows a better appreciation of the SIJ?

Answer 6

L/R Oblique view of SIJ

Question 7

list general indications for CT of the spine

Answer 7

1. Acute trauma (adults)
2. degenerative conditions
3. post-op assessment
4. infection
5. image guided intervention procedures
6. neoplasms
7. inflammatory lesions
8. congenital/developmental conditions
9. Cord syrinxes/masses (with MRI contraindicated)

Question 8

notes about CTs of lumbar spine

Answer 8

1. CT great for viewing bone
2. Basic protocol
   
   1. lower thoracic to SIJs (or less)
   2. Axial slices; reformatting to sagittal and coronal planes
3. Other CTs
   
   1. CT myelogram
   2. CT with contrast (tumor, infection)
   3. Abdominal/Pelvic CT

Question 9

list general indications for MRI of the spine

Answer 9

1. acute trauma with suspected cord encroachment
2. DDD
3. neoplasm
   
   1. diagnosis and intervention f/u
4. intrinsic spinal cord pathology
5. pre and post-op assessment (soft tissues, vertebroplasty)
6. meningeal abnormalities
7. infection
   
   1. disc space infections
   2. epidural abscess

Question 10

list incidental imaging findings in the lumbar spine region

Answer 10

1. disc protrusion → high prevalence rates in asymptomatic populations (20-30%)
2. spondylolysis → pars defect reported in asymptomatic vs symptomatic populations
   
   1. 7-10% in asymptomatic
   2. 9% in symptomatic
3. spondylolisthesis → 3-4 mm anterior slippage advocated as a threshold for clinical instability

Question 11

characteristics of a bulging disc

Answer 11

1. these are not herniations
2. involve 50-100% circumference
   
   1. described as either symmetric or asymmetric

Question 12

what are the 2 types of herniations?

Answer 12

protrusions and extrusions

Question 13

describe protrusions and extrusions

Answer 13

1. Protrusion
   
   1. broad-based = 25-50% (total of 90-180 degrees)
   2. focal = <25% (less than 90 degrees)
2. Extrusions
   
   1. narrower neck
   2. sequestered or free fragment

Question 14

how are herniation locations described?

Answer 14

1. by plane
   
   1. axial plane divided into zones
   2. sagittal plane divided into levels

Question 15

list ACR appropriateness criteria to consider in the lumbar spien

Answer 15

1. Suspected spine trauma
2. Suspected spine trauma-child
3. low back pain
4. back pain - child
5. chronic back pain: suspected sacroilitis/spondyloarthropathy
6. stress (fatigue/insufficiency) fracture, including sacrum, excluding other vertebrae

Question 16

what initial imaging study is most appropriate for a patient that is age greater than or equal to 16 years with blunt trauma meeting criteria for thoracic and lumbar imaging?

Answer 16

CT thoracic and lumbar spine

Question 17

for a pt age greater than or equal to 16 years what next imaging study is most appropriate if acute thoracic/lumbar spine injury has been detected on radiographs or noncontrast CT with neurologic abnormalities?

Answer 17

MRI thoracic and lumbar spine

Question 18

what initial imaging study is most appropriate for a child (younger than 16) with suspected thoracolumbar spine trauma?

Answer 18

Radiography thoracic and lumbar spine

Question 19

what initial imaging study is most appropriate for a patient with acute low back pain with/without radiculopathy, no red flags and no prior management?

Answer 19

no imaging

Question 20

what initial imaging study is most appropriate for a pt with subacute or chronic LBP with/without radiculopathy, no red flags, and no prior management?

Answer 20

no imaging

Question 21

what initial imaging study would be most appropriate for a pt with subacute or chronic LBP with/without radiculopathy? Additionally, they are a surgical or intervention candidate with persistent or progressive symptoms during/following 6 weeks or optimal medical management.

Answer 21

MRI lumbar spine

Question 22

What initial imaging study is most appropriate for a pt with LBP with suspected cauda equina syndrome?

Answer 22

MRI lumbar spine

Question 23

What initial imaging study is most appropriate for a pt with LBP and a history of prior lumbar surgery with/without radiculopathy. They have new or progressing symptoms or clinical findings

Answer 23

Radiography lumbar spine

MRI lumbar spine

Question 24

what initial imaging study is most appropriate for a pt with LBP with/without radiculopathy. Along with one or more of the following: low-velocity trauma, osteoporosis, elderly individual, or chronic steroid use.

Answer 24

radiography lumbar spine

MRI lumbar spine

CT lumbar spine

Question 25

what initial imaging study is most appropriate for a pt with LBP with/without radiculopathy. Along with one or more of the following: suspicion of cancer, infection, or immunosuppression.

Answer 25

MRI lumbar

Question 26

for a child with back pain and none of the following clinical red flags (constant pain, night pain, radicular pain, pain lasting >4 weeks, abnormal neuro exam), what initial imaging is most appropriate?

Answer 26

no imaging