SI Joints Sacrum/Coccyx Scoliosis

Question 1

Label 1-3

Answer 1

1. L4, L5, illiac crest
2. S1 and ASIS
3. Coccyx, pubic symph, and greater trochanter

Question 2

How do you demonstrate AP L5-S1?

Answer 2

AP Axial

Question 3

When demonstrating S.I. Joints, what is better, PA or AP?

Answer 3

PA

Question 4

True or false?

Posteriorly SI joints are more medial, anteriorly they are more lateral.

Answer 4

True

Question 5

Label the yellow, blue and red lines.

Answer 5

Yellow: SI joints
Blue: Illium
Red: Superior pubic ramus

Question 6

What should be seen on a S.I. Joints – AP Axial

Answer 6

1. No rotation
2. Both S.I. joints demonstrated without superimposition from the superior pubic ramus
3. Open lumbosacral joint L5/S1 SPOT

Question 7

Why is PA Axial S.I. Joints better than AP?

Answer 7

1. The CR divergence aligns nicely with the anatomy, and will help to open and visualize the joint better.
2. Offers better gonadal protection

Question 8

Why do we not do PA axial joints all the time instead of AP?

Answer 8

1. Easier to have them on their back,
2. to reduce magnification, sometimes
3. your patient cannot be on their stomach
4. Less overlap of illium and sacrum

Question 9

Where should the laser be exiting for PA axial SI joints?

Answer 9

Laser should not be exiting at the ASIS; it should exit 2 inches below

Question 10

Label 1-23

Answer 10

Question 11

What is the issue with this image?

Answer 11

Too much of a caudad was used

Question 12

What does an RPO SI joint demonstrate?

Answer 12

The left SI joint

Question 13

What does an LPO SI joint demonstrate?

Answer 13

The right side

Question 14

What should be seen on an SI joint AP oblique?

Answer 14

1. Open S.I. joint
2. AP- center on the raised side
3. Minimal overlapping of the ilium and the sacrum

Question 15

What are the issues with this image? What way was the patient rotated for this SI joints?

Answer 15

1. The CP on the PA Axial is a bit low,
2. Not enough caudad angle was used
   -Patient rotated RPO due to the overlapping in the SI joints

Question 16

What are the issues with these two images?

Answer 16

Left image:
-CP is slightly too lateral and inferior. (still a good image)
Right image:
-SI joint is rotated just a bit too much (nearly 45 degrees) so nearly closing the SI joint space.

Question 17

What projection and position is the Bisecting angle method?

Answer 17

AP axial sacrum

Question 18

What should be seen on an AP Axial Sacrum?

Answer 18

1. No rotation
2. Entire sacrum with no foreshortening
3. Pubic bones not overlapping sacrum
4. Tight collimation
5. Open sacral foramina

Question 19

What would happen if we didnt use an angle in an AP coccyx projection?

Answer 19

The tip of the coccyx would be covered by the superior pubic ramus without any angle

Question 20

What does the CR hit first in an AP coccyx projection? Why is this important?

Answer 20

The CR ‘hits’ the superior pubic bone first, moving it inferiorly – the coccyx is less distorted

Question 21

What should be seen on an AP coccyx?

Answer 21

1. Entire coccyx demonstrated with segments not superimposed
2. No rotation
3. Tight collimation
4. No superimposition with the pubic bones
5. Coccyx must be superior (and should be in line with the pubic symphysis)

Question 22

What is the issue with this image?

Answer 22

Patient is rotated slightly LPO

Question 23

What is the main issue with this image? What projection is this?

Answer 23

-The coccyx is superimposed on the Pubic Bone, so either not enough angle or the incorrect angle direction was used.
-AP coccyx projection

Question 24

How much more posterior is the sacrum to the ASIS?

Answer 24

3-4 inches posterior

Question 25

How much more posterior and inferior is the coccyx to the ASIS?

Answer 25

Approximately 4” inferior and 3-4” posterior to the ASIS.

Question 26

What should be seen on a lateral sacrum/coccyx?

Answer 26

1. Sacrum and coccyx should both be seen clearly 2. Tight collimation 3. Superimposed acetabula and greater sciatic notches

Question 27

What are the red lines demonstrating?

Answer 27

The right acetabular and siatic notch

Question 28

What is the main issue with this image?

Answer 28

A caudad angle was not used

Question 29

What is the main issue with this image?

Answer 29

Could have centered more posterior

Question 30

What are the 2 main issues with this image of an AP axial sacrum?

Answer 30

1. More of a cephalad angle could have been used 2. Minimal rotation (RPO) occuring

Question 31

Critique this image:

Answer 31

1. Lateral view has perfect superimposition of the Greater Sciatic Notches and acetabula. 2. Collimator could have been turned to match the anatomy. 3. Marker should be inluded

Question 32

In what situation would we do a lateral coccyx projection?

Answer 32

Done as a follow up after we have determined that just the coccyx is fractured

Question 33

What should be seen on a lateral coccyx?

Answer 33

Lateral Coccyx visualized completely, including distal end of sacrum

Question 34

What causes Scoliosis?

Answer 34

Idiopathic, functional, neuromuscular, degenerative

Question 35

What does ideopathic mean?

Answer 35

Idiopathic: Has no known cause

Question 36

When does ideopathic scoliosis occur?

Answer 36

Idiopathic typically appears during adolescence

Question 37

What changes must be made to techniques for scolliosis imaging?

Answer 37

High kVp (and low mAs)

Question 38

Should a scoliosis patient be AP or PA?

Answer 38

PA

Question 39

# True or false? Initial Imaging should always be performed erect for scoliosis patients.

Answer 39

True

Question 40

# True or false? The curveture of a scoliosis' patient spine is always larger than anticipated.

Answer 40

True-collimate widely

Question 41

What is the purpose of this structure?

Answer 41

To provide lead shieling to scoliosis patients for the breasts

Question 42

How many cassettes are used in scoliosis imaging with Computed Radiography?

Answer 42

2-3 CR cassettes can be attached together to achieve the desired length

Question 43

What is the name of the process that combines all of the images taken for scolliosis in computed radiography cassettes?

Answer 43

Software uses image stitching

Question 44

# True or false? With CR systems, the length of the SID is determined by the length of the anatomy you are imaging for scolliosis image stitching.

Answer 44

True

Question 45

What does it mean to have malignant scoliosis?

Answer 45

Malignant scoliosis: Changing so dramatically and needs surgery

Question 46

What are the 2 types of scoliosis?

Answer 46

1. Non-Structural (Secondary or Compensatory) 2. Structural

Question 47

What type of scoliosis has a temporary curvature?

Answer 47

Non-Structural (Secondary or Compensatory) scoliosis

Question 48

What type of scoliosis can also be called a primary curve?

Answer 48

Structural scoliosis

Question 49

When does Non-Structural (Secondary or Compensatory) scoliosis disappear?

Answer 49

Curve disappears when supine, with side-bending, or when the cause is removed

Question 50

# True or false? Curve does not disappear when supine or with side-bending with structural scoliosis?

Answer 50

True

Question 51

What are some symptoms of Non-Structural (Secondary or Compensatory) scoliosis?

Answer 51

Muscle spasm, leg length discrepancy, hip dysplasia, poor posture, or just compensates for structural curve

Question 52

Is structual scoliosis permentent?

Answer 52

Curvature is permanent (unless treatment is offered)

Question 53

If a primary curve is large enough, what does the spine do to compensate?

Answer 53

1. Body produces a “Compensatory” curve (Secondary, Non-Structural) to keep the body aligned 2. Compensatory curve will be in the opposite direction from the primary or structural curve

Question 54

When a compensatory curve is created from a primary curvature, at what situation is it naturally eliminated?

Answer 54

When supine, eliminating gravity eliminates the compensatory curve

Question 55

Which way do the vertebral bodies rotate in relation to the primary curvature?

Answer 55

Vertebral body rotates towards convex side of curve

Question 56

Absorb information on this slide in case you need it for the exam :)

Answer 56

:-)

Question 57

What is the purpose of doing a AP/PA Upright examination for scoliosis?

Answer 57

To assess the degree of curvature left to right with the force of gravity

Question 58

What is the purpose of doing a AP/PA Supine/Prone examination for a scoliosis series?

Answer 58

to assess Structural from Non-structural curves

Question 59

What is the purpose of doing a AP/PA With Lateral Bending examination for a scoliosis series?

Answer 59

To assess Primary from Secondary curves And Mobility

Question 60

What is the purpose of doing a Lateral Upright examination for a scoliosis sereis?

Answer 60

To assess the degree of Kyphosis or Lordosis – degree of anterior or posterior curvature

Question 61

What is the cobbs angle?

Answer 61

Determines the vertebra whose endplates are most tilted towards each other

Question 62

How do you find the degree of curvature in a scoliosis patient?

Answer 62

1. Lines are drawn along the top of the superior tilted vertebra and the bottom of the inferior tilted vertebra 2. Two more lines are drawn at an angle of 90° to these lines, so that they intersect 3. The resulting angle = Cobb Angle

Question 63

With the cobbs angle, what does an angle that is less than 20 degrees indicate?

Answer 63

Normal spine

Question 64

With the cobbs angle what does a 20-40 degrees angle indicate?

Answer 64

Need for brace (can stop progression if caught early on)

Question 65

With the cobbs angle, what does an angle that is >40-50 degrees indicate?

Answer 65

Need for rods, spinal fusion

Question 66

# True or false? There is no minimum degree of curvature that will necessitate surgery.

Answer 66

True

Question 67

What are the rods called in scoliosis patients that have had surgery?

Answer 67

Harrington rods

Question 68

What is the purpose of doing side bending images in scoliosis series?

Answer 68

To assess structural from non-structural curves

Question 69

What is the primary and secondary curvature in the spine?

Answer 69

Lumbar curve is secondary Thoracic is primary