Bontrager 9 Lumbar Spine, Sacrum, Coccyx - Part 2

Front 1

How should the knees be positioned for all projections of the lumbar spine?

Back 1

Flexed
Greater patient comfort
Less forward flexion of the pelvis

Front 2

What are the advantages of the PA projection of the lumbar spine over the AP projection?

Back 2

Better visualization of disc spaces
Lower ovarian dose in females (15-30% less)

Front 3

What are the disadvantages of the PA projection of the lumbar spine over the AP projection?

Back 3

Magnification
Loss of detail

Front 4

Why is close collimation vital when using high-kV technique of the spine?

Back 4

Reduce scatter and fogging

Front 5

Which requires greater kV, AP or lateral projections of the spine?

Back 5

Lateral
Greater part thickness

Front 6

How is the lead mat on the table-top helpful when doing images of the lumbar spine?

Back 6

Increases collimation to reduce scatter

Front 7

What is the minimum SID for lumbar spine projections?

Back 7

40"

Front 8

How is the imaging technique altered in patients with osteoporosis?

Back 8

Decreased kV of mAs

Front 9

When is CT evaluation of the spine indicated?

Back 9

Fractures, disc disease, neoplastic disease
Evaluation of vertebral canal

Front 10

When is MRI evaluation of the spine indicated?

Back 10

Evaluation of soft-tissue structures, such as the cord and intervertebral discs and disc-spaces

Front 11

When is NM evaluation of the spine indicated?

Back 11

Metastasis, inflammatory conditions, Paget's disease, osteomyelitis, primary bone malignancies

Front 12

When is bone densitometry indicated?

Back 12

Osteoporosis
Can detect bone loss as little as 1%
Conventional radiography needs a minimum of 30% bone loss to be detected

Front 13

What are the causes of loss of bone mass?

Back 13

Osteoporosis
Hyperparathyroidism
Estrogen deficiency
Steroid use
Advanced age & lifestyle factors

Front 14

When is myelography indicated?

Back 14

Lesions of the spinal canal, nerve roots and discs
Much less commonly used because of CT & MRI

Front 15

What is ankylosing spondylitis?

Back 15

Inflammatory autoimmune disease
Starts at sacroiliac joints and progresses cephalad
Causes fusion of intervertebral and costovertebral joints
More common in men

Front 16

What are the common causes of vertebral body compression fractures?

Back 16

Osteoporosis
Trauma
Metastatic disease

Front 17

What are 'chance' fractures?

Back 17

Hyperflexion forces fracturing the vertebral body
Posterior vertebral elements may be fractured too
Common lap-type seat belt injury

Front 18

What is HNP

Back 18

Herniated nucleus pulposus
Nucleus pulposus protrudes through the annulus
Occurs most commonly at the lower lumbar levels causing 'sciatica'
Not seen on plain radiographs - use MRI or CT

Front 19

What is lordosis?

Back 19

Abnormal concave curvature of the spine
Seen on lateral images
May occur in pregnancy, obesity or tuberculosis

Front 20

What is metastatic disease of the spine?

Back 20

Cancers that spread to the spine

Front 21

What are osteolytic lesions?

Back 21

Metastatic lesions that destroy bone
Have irregular margins

Front 22

What are osteoblastic lesions?

Back 22

Proliferative bony lesions

Front 23

What are combined lesions (osteolytic & osteoblastic)?

Back 23

Moth-eaten appearance as bone is destroyed and replaced

Front 24

What is scoliosis?

Back 24

Lateral curvature of the vertebral column

Front 25

What is spina bifida?

Back 25

Congenital lesion where posterior parts of the vertebrae fail to develop
Most often at L5

Front 26

What is osteogenesis imperfecta?

Back 26

Hereditary disorder
Bones abnormally soft and fragile
Patients often very short
Wide cranial sutures

Front 27

What is spondylolisthesis?

Back 27

Forward movement of one vertebra
Usually results from developmental defect in pars interarticularis
Can result in severe osteoarthritis
Most common at L5-S1
May require spinal fusion

Front 28

What is spondylolysis?

Back 28

Dissolution of the vertebra with separation of the pars interarticularis
Scottie Dog appears to have a broken neck

Front 29

Where is the CR positioned for AP projection of the lumbar spine?

Back 29

L4-5
Suspend breathing
IR 35 x 43

Front 30

What is visualized with the AP projection of the lumbar spine?

Back 30

Lumbar vertebral bodies, joints, processes
SI joint and sacrum
Grid

Front 31

What is the body position for AP or PA obliques of the lumbar spine?

Back 31

45 degree rotation
(50 degrees for facets of L1-2)
(30 degrees for facets of L5-S1)

Front 32

Where is the CR for AP or PA obliques of the lumbar spine?

Back 32

L3 (2" above iliac crests)
Perpendicular and centered to IR
Suspend breathing

Front 33

What is best visualized with the oblique views of the lumbar spine?

Back 33

Facet joints
Pars interarticularis

Front 34

How is the patient with scoliosis positioned for lateral view of the spine?

Back 34

With convexity down

Front 35

Where is the CR positioned for a lateral lumbar spine?

Back 35

L4-5

Front 36

What is best visualized with a lateral projection of the lumbar spine?

Back 36

Intervertebral foramina
Intervertebral joints
Spinous processes
L5-S1 junction

Front 37

What is the IR size for a lateral L5-S1 image?

Back 37

8x10"

Front 38

Where is the CR placed for an L5-S1 lateral image?

Back 38

1.5" inferior to iliac crest
2" posterior to ASISO
May angle 5-8 degrees caudat is less support used

Front 39

What is the indication of the L5-S1 lateral image?

Back 39

Spondylolisthesis of L4-5 or L5-S1
Other L5-S1 pathologies

Front 40

What is the patient position for the AP axial L5-S1 projection?

Back 40

Supine with head pillow and support under knees

Front 41

How is the CR angled for the AP axial L5-S1 projection?

Back 41

30 degrees cephalad in males
35 degrees cephalad in females

Front 42

What are the indications AP axial L5-S1 projection?

Back 42

L5-S1 pathology
Sacroiliac joint pathology

Front 43

What is the patient position for the AP (PA) scoliosis series?

Back 43

Erect or supine
Often both done for evaluation

Front 44

What is the IR position for a AP (PA) scoliosis series?

Back 44

Lower margin 1-2" below iliac crests

Front 45

What is the CR position for AP (PA) scoliosis series?

Back 45

Perpendicular, centered to IR

Front 46

What are the indications for the erect lateral position?

Back 46

Spondylolisthesis
Evaluation of lordosis or kyphosis

Front 47

Where is the IR positioned for the erect lateral image?

Back 47

1-2" below iliac crests

Front 48

Where is the CR positioned for the erect lateral image?

Back 48

Perpendicular and centered to IR

Front 49

What is the Ferguson method?

Back 49

PA spine images erect and then with one knee flexed

Front 50

Why is the Ferguson method used?

Back 50

Differentiates primary curve deformities from compensatory deformities.
Technique otherwise same as AP spine

Front 51

Why is the right and left bending AP (PA) projections used?

Back 51

Assess range of motion of vertebral column
Patient asked to bend as far as possible
Technique same as supine AP spine

Front 52

Why are the lateral hyperextension/hyperflexion projections used?

Back 52

Assess mobility of spinal fusion sites
Patient flexes and extends as far as possible
Technique otherwise same as lateral spine

Front 53

What is the patient position for the AP axial sacrum position?

Back 53

Supine with knees supported and flexed
Arms at side

Front 54

What special instructions are give to patients prior to AP axial sacral imaging?

Back 54

Empty bladder
Possible enema

Front 55

What is the CR position for AP axial sacral imaging?

Back 55

15 degrees cephalad (caudad for PA images)
2" above symphysis pubis

Front 56

What is best visualized by AP axial sacral imaging?

Back 56

SI joint
L5-S1 anatomy

Front 57

How is the patient positioned for AP axial coccyx images?

Back 57

Supine, knees supported and flexed, pillow
Arms at side

Front 58

How is the CR positioned for AP axial coccyx images?

Back 58

10 degrees caudad
Centered 2" above symphysis pubis

Front 59

What is the patient position for lateral sacrum and coccyx images?

Back 59

Full lateral
Pillow and knees flexed with padding between knees

Front 60

What is the CR position for lateral sacrum and coccyx images?

Back 60

Perpendicular to IR
3-4" posterior to ASIS

Front 61

What is the CR position for lateral coccyx images?

Back 61

3-4" posterior to ASIS
2" distal to ASIS

Front 62

What is the CR position for AP axial projections of the sacroiliac joints?

Back 62

30-35 degrees cephalad (males - 30, females - 35)
Midline 2" below ASIS

Can be done as PA with caudad angulation at L4

Front 63

What is the patient position for LPO or RPO of the SI joints?

Back 63

25 - 30 degrees of rotation (side of interest elevated)
Support elevated hip and flex knee

Front 64

What is the CR position for LPO or RPO of the SI joints?

Back 64

1" medial to upside ASIS