Sacrum, Coccyx, and SI Joints

Question 1

Anatomy of the Sacrum and Coccyx

Answer 1

Question 2

Anatomy of the Sacroiliac Joints

Answer 2

Question 3

What are the routine projections, SID, and kVp of sacrum and coccyx films?

Answer 3

Routine Projections = AP axial Sacrum, AP axial Coccyx, and Lateral

SID = 40”

kVp = 80

Question 4

AP Axial Sacrum

Patient is ___ with legs extended out straight.

Direct CR to the ___ plane ___ inches ___ to the pubic symphysis at angle of ___° ___.

Cone to the ___ and use markers.

This projection should demonstrate the entire sacrum centered on the film without ___.

Answer 4

AP Axial Sacrum

Patient is supine with legs extended out straight.

Direct CR to the midsaggital plane 2 inches superior to the pubic symphysis at angle of 15° cephalad.

Cone to the sacrum and use markers.

This projection should demonstrate the entire sacrum centered on the film without rotation.

Question 5

AP Axial Coccyx

With the patient still in the ___ position, direct CR ___ inches ___ to the pubic symphysis at an angle of ___° ___.

This projection should demonstrate the coccyx in its entirety, centered, and without ___.

Answer 5

AP Axial Coccyx

With the patient still in the supine position, direct CR 2 inches superior to the pubic symphysis at an angle of 10° caudad.

This projection should demonstrate the coccyx in its entirety, centered, and without rotation.

Question 6

Lateral Sacrum and Coccyx

The patient is in a ___ ___ ___ position.

Position the IR so that the ___ border at the level of the ___ of the ___.

Direct the CR through the sacrum and coccyx to the midpoint of the IR.

Cone down to the sacrum and coccyx.

This projection will demonstrate a true lateral view of the ___ and ___.

Answer 6

Lateral Sacrum and Coccyx

The patient is in a recumbent left lateral position.

Position the IR so that the upper border at the level of the crest of the ilium.

Direct the CR through the sacrum and coccyx to the midpoint of the IR.

Cone down to the sacrum and coccyx.

This projection will demonstrate a true lateral view of the sacrum and coccyx.

Question 7

What are the routine projections, SID, and kVp of the sacroiliac joints?

Answer 7

Routine Projections = AP axial, AP oblique projections (RPO and LPO)

SID = 40”

kVp = 80

Question 8

AP Axial Sacroiliac Joints

Position the patient ___ on the table with the lower legs extended outward.

Direct the CR ___° ___ and center ___ inches ___ to the pubic symphysis.

___ respiration for exposure.

This projection should include the ___ junction as well as the ___ joints.

Answer 8

AP Axial Sacroiliac Joints

Position the patient supine on the table with the lower legs extended outward.

Direct the CR 30° cephalad and center 1.5 inches superior to the pubic symphysis.

Suspend respiration for exposure.

This projection should include the lumbosacral junction as well as the sacroiliac joints.

Question 9

Oblique Sacroiliac Joints (RPO and LPO)

Position the patient ___ on the table.

Elevate the side being examined about ___-___°.

Direct the CR ___ inch ___ to the elevated ___.

Use the ___ position to demonstrate the right joint, and the ___ position to demonstrate the left joint (side ___ is side demonstrated).

Respiration is ___ for exposure.

Both sides are examined for ___.

Answer 9

Oblique Sacroiliac Joints (RPO and LPO)

Position the patient supine on the table.

Elevate the side being examined about 25-30°.

Direct the CR 1 inch medial to the elevated ASIS.

Use the LPO position to demonstrate the right joint, and the RPO position to demonstrate the left joint (side up is side demonstrated).

Respiration is suspended for exposure.

Both sides are examined for comparison.