Hip and PelvisHip and Pelvis

Chapter 6Chapter 6

Hip APHip AP

• Facility IdentificationFacility Identification• Correct Marker PlacementCorrect Marker Placement• No Preventable ArtifactsNo Preventable Artifacts• Correct Film Size Correct Film Size (10 x 12 lw unless (10 x 12 lw unless

indicated)indicated)

Hip APHip AP

• DensityDensity– Controlled by mAsControlled by mAs– Overall the density is not too dark or too Overall the density is not too dark or too

lightlight

• ContrastContrast– Optimal kVp 75-85Optimal kVp 75-85– Bony trabecular patters and cortical Bony trabecular patters and cortical

outlines visualized as well as soft tissues outlines visualized as well as soft tissues (fat pads) of the hip are demonstrated(fat pads) of the hip are demonstrated

Hip APHip AP

• Pelvis is in true AP projectionPelvis is in true AP projection– The ischial spine is aligned with the The ischial spine is aligned with the

pelvic brimpelvic brim– The sacrum and coccyx are aligned with The sacrum and coccyx are aligned with

the symphysis pubis the symphysis pubis – The obturator foramen is openThe obturator foramen is open

Hip APHip AP

• Detecting rotation toward the Detecting rotation toward the affected hipaffected hip

• If the ischial spine is demonstrated If the ischial spine is demonstrated without pelvic brim superimpositionwithout pelvic brim superimposition

• The sacrum and coccyx are rotated The sacrum and coccyx are rotated away from the affected hipaway from the affected hip

• The obturator foramen is narrowedThe obturator foramen is narrowed

Hip APHip AP

• Detecting rotation away from the Detecting rotation away from the affected hipaffected hip

• The sacrum and coccyx are rotated The sacrum and coccyx are rotated toward the affected hiptoward the affected hip

• The ischial spine is closer to the The ischial spine is closer to the acetabulumacetabulum

• The obturator foramen is widenedThe obturator foramen is widened

Hip APHip AP

• The femoral neck is demonstrated The femoral neck is demonstrated without foreshorteningwithout foreshortening– The greater trochanter is demonstrated The greater trochanter is demonstrated

in profile laterallyin profile laterally– The lesser trochanter is superimposed The lesser trochanter is superimposed

by the femoral neckby the femoral neck

Hip APHip AP

• The femoral head and acetabulum The femoral head and acetabulum are in the center of the collimated are in the center of the collimated fieldfield

• Any orthopedic appliance are Any orthopedic appliance are located at the hip are included in located at the hip are included in their entirety.their entirety.

Hip APHip AP

• Gonadal shielding Gonadal shielding should be used on should be used on all males and all males and females if it may females if it may be placed so that be placed so that anatomy is not anatomy is not obstructedobstructed

Hip Frog leg LateralHip Frog leg Lateral

• The pelvis is in a true AP positionThe pelvis is in a true AP position– The ischial spine is aligned with the The ischial spine is aligned with the

pelvic brimpelvic brim– The sacrum and coccyx are aligned with The sacrum and coccyx are aligned with

the symphysisthe symphysis– The obturator foramen is openThe obturator foramen is open

Hip Frog leg LateralHip Frog leg Lateral

• The lesser trochanter is The lesser trochanter is demonstrated in profile mediallydemonstrated in profile medially

• The femoral neck superimposes the The femoral neck superimposes the greater trochantergreater trochanter– The neck if foreshortened and is ½ way The neck if foreshortened and is ½ way

between the femoral head and the between the femoral head and the lesser torchanterlesser torchanter

Hip AxiolateralHip AxiolateralDanielus MillerDanielus Miller

• Placing lead flat contact shields over Placing lead flat contact shields over the unused portion of the cassette the unused portion of the cassette will reduce scatter and help improve will reduce scatter and help improve contrastcontrast

Hip AxiolateralHip AxiolateralDanielus MillerDanielus Miller

• The femoral neck is demonstrated The femoral neck is demonstrated without foreshortening without foreshortening

• The greater and lesser trochanters The greater and lesser trochanters are about the same transverse levelare about the same transverse level

Hip AxiolateralHip AxiolateralDanulus MillerDanulus Miller

• If the angle formed between the femur If the angle formed between the femur and the central ray is too large, the and the central ray is too large, the trochanter is demonstrated proximal to trochanter is demonstrated proximal to the lesser trochanter and is the lesser trochanter and is superimposed by a portion of the superimposed by a portion of the femoral neckfemoral neck

• If the angle is too small, the greater If the angle is too small, the greater trochanter is demonstrated distal to the trochanter is demonstrated distal to the lesser trochanter. (this seldom occurs lesser trochanter. (this seldom occurs due to table top)due to table top)

Pelvis APPelvis AP

• Pelvis is demonstrated without Pelvis is demonstrated without rotationrotation– The ischial spines are aligned with the The ischial spines are aligned with the

pelvic brimpelvic brim– The sacrum and coccyx are aligned with The sacrum and coccyx are aligned with

the symphysisthe symphysis– The ilia and the obturator foramina are The ilia and the obturator foramina are

uniform in size and shapeuniform in size and shape

Pelvis APPelvis AP

• Male –vs- Female PelvisMale –vs- Female Pelvis– Male pelvis is more heart shapedMale pelvis is more heart shaped

• The obturator foramina and acetabula are The obturator foramina and acetabula are larger and more bulkylarger and more bulky

– Female pelvis is more ovalFemale pelvis is more oval

Pelvis APPelvis AP

• The femoral neck is demonstrated The femoral neck is demonstrated without foreshorteningwithout foreshortening– The greater trochanter is demonstrated The greater trochanter is demonstrated

in profile laterallyin profile laterally– The lesser trochanter is superimposed The lesser trochanter is superimposed

by the femoral neckby the femoral neck

Pelvis APPelvis AP

• Detecting rotation toward the Detecting rotation toward the affected hipaffected hip

• If the ischial spine is demonstrated If the ischial spine is demonstrated without pelvic brim superimpositionwithout pelvic brim superimposition

• The sacrum and coccyx are rotated The sacrum and coccyx are rotated away from the affected hipaway from the affected hip

• The obturator foramen is narrowedThe obturator foramen is narrowed

Pelvis APPelvis AP

• Detecting rotation away from the Detecting rotation away from the affected hipaffected hip

• The sacrum and coccyx are rotated The sacrum and coccyx are rotated toward the affected hiptoward the affected hip

• The ischial spine is closer to the The ischial spine is closer to the acetabulumacetabulum

• The obturator foramen is widenedThe obturator foramen is widened

Pelvis APPelvis AP

• All anatomy is included on the filmAll anatomy is included on the film– Inferior sacrum is in the center of the Inferior sacrum is in the center of the

filmfilm– The ilia, symphysis ischia acetabulum, The ilia, symphysis ischia acetabulum,

femoral necks and heads, greater and femoral necks and heads, greater and lesser trochanter are included on filmlesser trochanter are included on film

THE ENDTHE END