Sacrum and Coccyx

Question 1

• CR: supine, direct the CR 15 degrees cephalad and center it to a point 2 inches superior to the pubic symphysis.
• With the patient prone, angle the CR 15 degrees caudad and center it to the clearly visible sacral curve
• demonstrates the sacrum free of superimposition

Answer 1

AP / PA AXIAL PROJECTIONS
(SACRUM)

Question 2

• CR: Patient supine, direct the CR 10 degrees caudad and center it to a point about 2 inches superior to the pubic symphysis.
• With the patient prone, angle the central ray 10 degree cephalad and center it to the easily palpable coccyx.
• demonstrates the coccyx free of superimposition

Answer 2

AP / PA AXIAL PROJECTIONS
(COCCYX)

Question 3

Perpendicular and directed to the level of the ASIS and to a point 3.5 inches posterior.
- shows a lateral projection of the sacrum or coccyx

Answer 3

LATERAL PROJECTIONS
R or L position
Sacrum

Question 4

Perpendicular and directed toward a point 3.5 inches posterior to the ASIS and 2 inches inferior.
- shows a lateral projection of the sacrum or coccyx

Answer 4

LATERAL PROJECTIONS
R or L position
Coccyx

Question 5

• Seat the patient on the end of the radiographic table.
• Patient lean forward then grasp the legs or ankles to maintain the position.
• Center the IR to the vertically placed portion of the sacrum.
• CR: Perpendicular to the IR and the long axis of the sacrum.

Answer 5

AXIAL PROJECTION / NOLKE METHOD
(Sacral Vertebral Canal and Sacroiliac Joints)

Question 6

• shows the lower sacral vertebral canal, the junction of the sacrum and coccyx, and the last lumbar vertebra

Answer 6

slight flexion

Question 7

• shows a cross section of the upper and lower sacral vertebral canal. The sacroiliac joints are also demonstrated.

Answer 7

moderate flexion

Question 8

• shows the upper sacral vertebral canal projected into the angle formed by the ascending rami of the ischial bones just posterior to the pubic symphysis. The spinous process of the last lumbar segment is projected across the shadow of the canal.

Answer 8

hyperflexion

Question 9

CR OF AP AXIAL SACRUM

Answer 9

15 cephalad center 2 inches superior to the pubic symphysis

Question 10

CR OF PA AXIAL SACRUM

Answer 10

15 caudad, center to sacral curve

Question 11

CR OF AP AXIAL COCCYX

Answer 11

10 caudad, center 2 inches superior to pubic symphysis

Question 12

CR OF PA AXIAL coccyx

Answer 12

10 cephalad, center palpable coccyx