Sacrum & Coccyx

							          Sacrum & Coccyx
• The primary beam will pass through the
  general location of the ovaries. Unless the
  female patient of child bearing age is
  large, P-A views are taken.
• The bell will be used for male patients
  needing Sacrum or Coccyx views.
• Measurements are at the trochanters.


                                                1
            7.14 A-P Sacrum
• Measure: A-P at
  trochanters
• Protection: Bell for
  males, none for females
• SID: 40” Bucky
• Tube angle: 15 degrees
  cephalad
• Film: 8” x 10” I.D. up
  Portrait



                              2
               A-P Sacrum
• Patient stands facing
  the tube with back
  touching Bucky.
• Patient may hold onto
  the Bucky.
• Locate the ASIS and
  the symphysis pubis



                            3
               A-P Sacrum
• Horizontal CR:
  midway between the
  ASIS and pubis or 1.5
  inches below the
  ASIS.
• Vertical CR: mid
  sagittal plane
• Center film to
  horizontal CR

                            4
                  A-P Sacrum
• Collimation: slightly less
  than film size
• Breathing Instructions:
  Full Expiration
• Make exposure and let
  patient breathe and
  relax




                               5
            A-P Sacrum Film
• There should be no
  rotation.
• The entire sacrum
  should be seen.
• The S.I. Joints should
  be well visualized.
• The Bell should not
  obstruct the view.


                              6
           7.15 P-A Sacrum
• Measure: A-P at
  trochanters
• Protection:
  positioning
• SID: 40” Bucky
• Tube angle: 15°
  caudal
• Film: 8” x 10” Regular
  I.D. up Portrait

                             7
                  P-A Sacrum
• Patient stands facing the
  Bucky. Get the patient as
  close to the Bucky as
  possible.
• Check feet and torso for
  rotation.
• Locate the PSIS
• Horizontal CR: 1” to 2”
  below the PSIS or mid
  sacrum


                               8
                  P-A Sacrum
• Vertical CR: mid sagittal
• Collimation: slightly less
  than film size.
• Breathing Instructions:
  Full expiration
• Make exposure and let
  patient breathe and
  relax




                               9
             P-A Sacrum Film
• There should be no
  rotation.
• Sacrum and Sacroiliac
  Joints should be well
  visualized.
• Taken only on females
  of childbearing age that
  are not too large.




                               10
              7.16 A-P Coccyx
• Measure: A-P at
  trochanters
• Protection: Bell for
  males, none for females
• SID: 40” Bucky
• Tube Angle: 10 degrees
  caudal
• Film: 8” X 10” regular I.D.
  up portrait



                                11
                  A-P Coccyx
• Patient stands facing the
  tube with feet shoulders
  width apart.
• Make sure patient is as
  close to Bucky as
  possible.
• Locate the ASIS and
  symphysis pubis




                               12
                  A-P Coccyx
• Horizontal CR: 2” above
  the symphysis pubis or
  midway between the
  ASIS and symphysis
  pubis
• Vertical CR: mid sagittal
• Center film to horizontal
  CR
• Collimation: slightly less
  than film size


                               13
                 A-P Coccyx
• Breathing Instructions:
  Full Expiration
• Make exposure and let
  patient relax.




                              14
            A-P Coccyx Film
• Should see distal
  sacrum and coccyx
• No evidence of rotation
• Bell should not obscure
  view of coccyx
• This view can also be
  used to evaluate pubic
  fractures.




                              15
7.17 P-A Coccyx
        • Measure: A-P at
          trochanters
        • Protection: position
        • SID: 40” Bucky
        • Tube Angle: 10 degrees
          cephalad
        • Film: 8” x 10” regular I.D.
          up Portrait




                                    16
P-A Coccyx
     • Patient stands facing
       the Bucky with feet
       shoulders width apart.
     • Make sure the patient
       is not rotated.
     • Patient should be as
       close to Bucky as
       possible.


                           17
P-A Coccyx
     • Horizontal CR: 2” above the
       level of the trochanters
     • Vertical CR: mid sagittal
     • Center film to horizontal
       CR.
     • Collimation: slightly less
       than film size.
     • Breathing Instructions:
       Full Expiration
     • Make exposure and let
       patient relax




                                     18
P-A Coccyx Film
        • Should see the distal
          sacrum and entire
          coccyx.
        • There should be no
          rotation
        • Gas in the bowel may
          reduce image quality




                                  19
 7.18 Lateral Sacrum & Coccyx
• Measure: Lateral at
  trochanters
• Protection: Lateral
  gonad shield
• SID: 40” Bucky
• No tube angle
• Film: 10” x 12” regular
  I.D. Up Portrait




                                20
      Lateral Sacrum & Coccyx
• Patient stands in lateral
  position with feet
  shoulders width apart.
• Have patient cross arms
  at shoulder level.
• Locate the Iliac Crest and
  Symphysis Pubis
• Horizontal CR: midway
  between Iliac Crest and
  Symphysis Pubis


                                21
      Lateral Sacrum & Coccyx
• Vertical CR: 2” to 3”
  posterior to mid coronal
  plane.
• Center film to Horizontal
  CR.
• Collimation Top to
  Bottom: slightly less than
  film size
• Collimation Side to Side:
  slightly less than film size or
  posterior skin

                                    22
     Lateral Sacrum & Coccyx
• Place Lateral Gonad
  Shield with curve
  following curve of sacrum
  to level of ASIS on females
  and above pubis on males.
• Breathing Instructions:
  Full Expiration
• Make exposure and let
  patient breathe and relax.



                                23
 Lateral Sacrum & Coccyx Film
• Should visualize from
  L5 to tip of coccyx.
• No evidence of patient
  rotation.
• Collimation will reduce
  scatter and improve
  detail.




                                24
  Lumbar Region Radiography
• Accurate positioning requires the doctor to
  locate the positioning landmarks.
  – Lumbar Spine: Iliac Crest, ASIS or PSIS
  – Sacrum or Coccyx: Symphysis Pubis, ASIS or
    Iliac Crest
• Gonad Shielding placement is critical.
  Improperly positioned shield will block
  view.

                                             25
      Full Spine Radiography
• Full spine views will require proper use of :
  – Accurate placement of filtration
  – Higher technical factors and complete
    exposures
  – Relatively high speed film
  – Modern x-ray generators
  – Accurate placement of gonad shielding.



                                              26
      Full Spine Radiography
• Follow up exams on young females can be
  done P-A to further reduce radiation
  exposure to breast tissue and ovaries.
• Some facilities will lower Para spinal shield
  to level just above the iliac crest.




                                             27
  Lumbar Region Radiography
• Because recumbent radiography
  straightens the lumbar spine, posterior
  oblique views are best taken recumbent.
• Horizontal Central Ray Placement:
  – A-P Lumbopelvic: 1” to 1.5 “ below iliac crest
  – Lateral & Oblique Views: 1” above iliac crest




                                                 28
  Lumbar Region Radiography
• Accurate positioning requires attention to
  the placement of the feet.
  – Shoulders width apart
  – Parallel to each other
  – Knees locked to check impact of leg length
    problems
• Back and buttocks should be touching
  Bucky

                                                 29
Sacrum & Coccyx Radiography
• Horizontal Central Ray:
  – Sacrum A-P : Midway between ASIS and
    Symphysis
  – Sacrum P-A: Two inches below PSIS
  – Coccyx A-P: Midway between ASIS and
    Symphysis or 2” above symphysis
  – Coccyx P-A: Midway between trochanters and
    PSIS


                                            30
Sacrum & Coccyx Radiography
• Horizontal Central Ray:
  – Lateral: Midway between Iliac Crest and
    Symphysis
• Proper collimation will reduce scatter and
  improve image quality




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