Sacrum, Coccyx, SI Joints, and Scoliosis Flashcards
SACRUM
-Five sacral segments fused together
• Base: superior border
• Articulates with the lumbar vertebra
• Sacral Promontory
• Sacral canal: continuation of the vertebral column
• Transmits sacral nerves
• 4 pairs of sacral foramina
• Apex: most inferior portion
• Articulates with the sacral cornua, and the coccyx
Sacrum: The auricular surfaces articulate with the _______
ilia
SACRUM/COCCYX: The ______ of the coccyx articulates with the ______ of the sacrum
Base, Apex
Coccygeal cornua projects superiorly and joins the ________ _________
sacral cornua
T or F: SACROILIAC JOINTS: The auricular surfaces of the wings of the sacrum articulate with the auricular surfaces of the wings of the ilia
True
The SI joints are functionally _____________
The SI joints are structurally ____________________________
-amphiarthroses (movement is limited)
-synovial, irregular gliding joints
AP and PA AXIAL SACRUM Positioning
AP:
-SID: 40
• 10 X 12 IR LW in bucky.
• Patient supine
• Adjust pelvis so both ASIS are equidistance to table top
• CR 15 degrees cephalic entering to 2 inches superior to the pubic symphysis at the MSP
• Suspend respiration
PA:
• Patient prone
• CR 15 degrees caudal centered to sacral curve, exiting at a point 2 inches superior to level of the pubic symphysis
• All else the same as AP
AP/ PA AXIAL SACRUM Evaluation Criteria
• Sacrum seen in its entirety
• Sacral curvature straightened by angled CR
• Pubic bones not overlapping sacrum
• Bony Trabeculae
AP and PA AXIAL COCCYX Positioning
-SID: 40 inches
AP:
• 10 X 12 IR LW in bucky
• Collimate to 8” x 10” (18 cm x 24 cm)
• Patient supine
• Adjust pelvis so both ASIS are equidistance to Table Top
• CR is 10 degrees caudal entering 2 inches superior to Pubic Symphysis at the MSP
• Suspend breathing
PA:
• Patient Prone
• CR 10 degrees cephalic for centered to the coccyx exiting at a point 2 inches superior to the level of the pubic symphysis
• All else the same as AP
AP/PA AXIAL COCCYX Evaluation Criteria
• Соссух centered to radiograph
• No superimposition from the pubic symphysis
• Distal segment in line with pubic symphysis
• Bony Trabeculae
LATERAL SACRUM/COCCYX Positioning
• 10 X 12 IR LW in bucky
•SID: 40 inches
• Patient in lateral recumbent position on affected side (left if no side indicated)
• Flex hips and knees and superimpose the knees
• Arms at right angles to the body
• Patient in true lateral
• CR perpendicular to 3.5 inches posterior to the elevated ASIS
• For coccyx only: center 3.5 inches posterior AND 2 inches distal to ASIS
• Collimate
• Place lead strip posterior to the patient at the collimation line
• Suspend respiration
LATERAL SACRUM/COCCYX Evaluation Criteria
• Lateral projection of the sacrum and coccyx
• Superimposed posterior margins of the ischia and ilia
• Soft tissue and bony trabeculae
AP AXIAL SI JOINTS (Ferguson Method) Positioning
• 10 X 12 IR LW in
•SID: 40 inches
• Patient supine
• Extend lower limbs
• CR Cephalic: 30 degrees for males and 35 degrees for females
• Center 1.5 inches superior to the Pubic Symphysis at the MSP
• Collimate to 8 x 10
• Suspend Respiration
AP AXIAL SI JOINTS Evaluation Criteria
• Symmetrical view of both SI joints
• Lumbosacral junction
• Open disk space L5- S1
• Bony trabeculae
AP OBLIQUE SI JOINTS Positioning
• 10 X 12 LW in bucky
•SID: 40 inches
• Patient Supine
• Elevate side of interest to 25 to 30 degree oblique
• Support lower thorax and upper thigh using positioning sponge
• Long axis of body parallel with long axis of Radiographic table
• CR perpendicular to 1 inch medial to the elevated ASIS
• Collimate to 6 X 10
• Suspend respiration
• Both sides are done for comparison
AP OBLIQUE SI JOINTS Evaluation Criteria
• SI Joint farthest from the IR demonstrated
• Joint space open with minimal superimposition
• Bony Trabeculae
