Femur & Pelvis. Flashcards
AP Femur. Clinical Indications:
Evaluates fractures and/or bone lesions
AP Femur. Minimum SID:
40” (102cm)
AP Femur. IR size:
14x17” (35x43cm) lengthwise
AP Femur. Grid?
Yes
AP Femur. kV range:
Analog: 75 +/- 5 kV.
DIgital: 75 - 85 kV.
AP Femur. Pt position:
Patient is in supine postion, Femur centered to midline of table.
AP Femur. Part position:
- Femur aligned to CR and midline of table or IR.
- With knee included: Rotate leg internally about 5 degrees.
- With hip included: Rotate leg, internally 15-20 degrees as for AP projection of the hip.
- To ensure knee joint is included on IR - lower IR margin should be about 2” (5cm) below knee joint.
- To ensure hip joint is included on the IR - Top of IR placed at the level of the ASIS.
AP Femur. Central Ray:
Perpendicular to femur and IR.
AP Femur. Recommended Collimation:
Closely on both side to femur.
End collimation to film borders.
AP Femur. Evaluation Criteria:
With knee included:
Distal 2/3rds of distal femur including knee joint.
Knee joint not fully open.
With hip included:
At least the proximal 1/3rd of femur along with the acetabulum and adjacent parts of pubis, ilium, and ischium.
AP Femur. Evaluation Criteria: Postion with knee included:
No rotation:
Femoral and tibial condyles appear symmetric.
Patella slightly toward medial femur.
Approximate half of fibular head superimposed by tibia.
Femur centered to collimated field and aligned with long axis of IR.
Knee joint space a minimum of 1” from distal IR margin.
Collimation to area of interest.
AP Femur. Evaluation Criteria: Position with hip included:
-Greater trochanter and femoral head and neck
in full profile without foreshortening.
-Lesser trochanter should not project beyond the medial border of the femur.
-Collimated field demonstrates entire hip joint and at least proximal third of femur.
Lateral projections of Femur. Mid and distal. Clinical Indications:
Mid and distal femur to include knee joint for detection and evaluation of fractures and /or bone lesions.
Lateral projections of Femur. Mid and distal. Minimum SID:
40” (102cm)
Lateral projections of Femur. Mid and distal. IR size:
14x17” (35x43cm) lengthwise.
Lateral projections of Femur. Mid and distal. Grid?
Yes
Lateral projections of Femur. Mid and distal. kV range:
Analog - 75 +/- 5 kV
Digital - 75-85 kV
Lateral projections of Femur. Mid and distal. Patient position:
Lateral recumbent.
Or supine for trauma.
Lateral projections of Femur. Mid and distal. Lateral recumbent:
- Not for trauma
- Knee is flexed about 45 degrees on affected side
- Femur aligned to midline of table
- Unaffected leg behind to prevent over rotation
- Include knee joint
- Second IR needed to include proximal femur and hip.
Lateral projections of Femur. Mid and distal. Trauma Lateromedial:
- Support placed under leg and knee and leg placed in true AP position.
- IR placed on edge against medial aspect of femur to include knee joint.
- Horizontal xray beam directed from lateral side.
Lateral projections of Femur. Mid and distal. Central Ray:
Perpendicular to femur and IR.
To midpoint of IR
MInimum 40” SID.
Lateral projections of Femur. Mid and distal. Collimation:
On both sides to femur with end collimation to IR borders.
Lateral projections of Femur. Mid and distal. Evaluation Criteria:
Distal 2/3rds of distal femur including knee joint.
Because of divergent X-ray beam knee joint will not appear open and distal margins of femoral condyles are not superimposed.
Lateral projections of Femur. Mid and distal. Evaluation Criteria: Position:
True lateral:
- Anterior and posterior margins of condyles superimposed.
- Femur centered to collimated field.
- Open patellofemoral joint space.
- Knee joint space on distal IR margin and a minimum of 1” from distal IR margin
- Collimation to area of interest.
Lateral projections of Femur. Mid and distal. Exposure:
- Correct use of anode heel effect results in near uniform density of femur.
- Use of compensating filter results in near uniform density (brightness)
- No motion: Clear sharp bony trabecular markings.
Mediolateral projection of Femur. Mid and PROXIMAL.
Do not attempt this position for patients with possible fracture of the hip or proximal femur.
Trauma projection: Trauma lateral hip.
Mediolateral projection of Femur. Mid and PROXIMAL. Clinical Indications:
Mid and proximal femur for evaluation of fractures and bone lesions.
Mediolateral projection of Femur. Mid and PROXIMAL. Minimum SID:
40” (102cm)
Mediolateral projection of Femur. Mid and PROXIMAL.
IR size:
14x17” (35x43cm) lengthwise.
Mediolateral projection of Femur. Mid and PROXIMAL.
Grid?
Yes
Mediolateral projection of Femur. Mid and PROXIMAL.
kV range:
Analog: 75 +/- kV
Digital: 80 - 85 kV
Mediolateral projection of Femur. Mid and PROXIMAL. Patient position:
Lateral recumbent affected side down.
Mediolateral projection of Femur. Mid and PROXIMAL.
Part position:
- Knee flexed about 45 degrees and femur aligned to midline of table.
- Unaffected leg is extended and supported behind affected knee.
- Patient rolls back posteriorly 15 degrees to prevent superimposition of proximal femur.
- Upper margin of IR placed at level of ASIS.
Mediolateral projection of Femur. Mid and PROXIMAL.
Central Ray:
Perpendicular to femur and IR, directed to midpoint of IR.
Mediolateral projection of Femur. Mid and PROXIMAL. Recommended collimation:
Closely on all four sides.
Mediolateral projection of Femur. Mid and PROXIMAL. Evaluation Criteria:
Proximal one-half to two-thirds of proximal femur including hip joint.
Proximal femur is not superimposed by opposite limb.
Mediolateral projection of Femur. Mid and PROXIMAL. Position:
True lateral:
Superimposition of greater and lesser trochanters.
Small part of lesser trochanter seen on medial side.
Most of greater trochanter superimposed by femoral neck.
Femur centered to collimated field.
Hip joint included and a minimum of 1” from proximal margin of IR
Collimated to area of interest.
AP Pelvis. Clinical Indications:
Fractures, joint dislocation, degenerative disease and bone lesions.
AP Pelvis. Minimum SID:
40” (102cm)
AP Pelvis. IR size:
14x17” (35x43cm) crosswise.
AP Pelvis. Grid?
Yes
AP Pelvis. kV range:
Analog: 80 +/- 5 kV
Digital:
AP Pelvis. Pt position:
Supine with arms at sides or across superior chest.
May be performed erect.
AP Pelvis. Part position:
- MSP of pt aligned to centerline of IR and CR.
- Pelvis not rotated - ASIS equidistant.
- Separate legs and internally rotate long axis of feet and lower limbs 15-20 degrees (if no fracture is suspected.)
- Sandbags/tape.
AP Pelvis. Central Ray:
- Perpendicular to IR.
- Enters midway between level of ASIS and pubic symphysis.
- IR centered to CR
- NOTE* IF performed as part of hip routine, centering is about 2 inches lower to level of mid femoral heads or necks to include more of the proximal femora.
AP Pelvis. REcommended Collimation:
On all four sides to the anatomy of interest.
AP Pelvis. Respiration:
Suspended during exposure.
AP Pelvis. Evaluation Criteria:
Pelvic girdle.
L5, sacrum & coccyx
Femoral heads, necks and greater trochanter.
AP Pelvis. Position:
Lesser trochanters not visible or just tips visible.
Greater trochanters equal in size and shape.
AP Pelvis. Signs of no rotation include:
- Symmetric wings, ischial spines and obturator foramen.
- Foreshortened or closed obturator foramen indicates rotation in that direction.
- Entire pelvis and superior femora without foreshortening and in collimated field.
- Collimation to area of interest.
AP Pelvis. Exposure:
Optimal exposure visualizes L5, sacrum, femoral heads, acetabula without overexposing ischium and pubic bones.
AP Bilateral “Frog-leg” (Modified Cleaves method).
This position is not attempted on patients with destructive hip disease, or with potential hip fracture.
AP Bilateral “Frog-leg” (Modified Cleaves method). Clinical Indications:
Non trauma hip or development dysplasia of hip (DDH) also known as congenital hip dislocation (CHD).
AP Bilateral “Frog-leg” (Modified Cleaves method). Minimum SID:
40” (102cm)
AP Bilateral “Frog-leg” (Modified Cleaves method). IR size:
14x17” (35x43cm) crosswise
AP Bilateral “Frog-leg” (Modified Cleaves method). Grid?
yes
AP Bilateral “Frog-leg” (Modified Cleaves method). kV range:
Analog: 80 ± 5 kV
Grid systems 80-85 kV range
AP Bilateral “Frog-leg” (Modified Cleaves method). Pt position:
Supine with arms across chest.
AP Bilateral “Frog-leg” (Modified Cleaves method). Part position:
- Patient aligned to midline of table and/or IR and CR.
- Equal distance of ASIS - no rotation
- IR centered to CR at level of femoral necks.
- Top of IR approximately at level of crests
- Knees flexed about 90º.
- Both femora abducted 40º to 45º from vertical.
- Ensure both femora are abducted equal amount with no rotation of pelvis
AP Bilateral “Frog-leg” (Modified Cleaves method). Note concerning less abduction of femora:
20º to 30º from vertical provides for least foreshortening of femoral necks, however, this foreshortens the entire proximal femora.
AP Bilateral “Frog-leg” (Modified Cleaves method). Central Ray:
Perpendicular to IR to a point 3 inches below level of ASIS (1” superior to pubic symphysis.)
AP Bilateral “Frog-leg” (Modified Cleaves method). Recommended collimation:
To IR borders on 4 sides.
AP Bilateral “Frog-leg” (Modified Cleaves method). Respiration:
Suspend during exposure.
AP Bilateral “Frog-leg” (Modified Cleaves method). Evaluation Criteria:
Femoral heads, necks, acetabulum and trochanteric area.
AP Bilateral “Frog-leg” (Modified Cleaves method). Position:
No rotation:
- Symmetric pelvic bones, wings, obrurator foramina and ischial spines if present. - Heads, neck and greater and lesser trochanters symmetric. - Lesser trochanters projected beyond medial margin of femora. - Greater trochanters superimposed over femoral necks which appear foreshortened.
AP Bilateral “Frog-leg” (Modified Cleaves method). Exposure:
Margin of femoral head and acetabulum through pelvis structures. Proximal femora not overexposed.