AP Proximal Femur is a radiography positioning projection of the Lower Extremity. Supine, leg internally rotated 15-20 degrees. Hip joint included. The centering point is located midway between hip and knee on the affected femur. include the hip joint on the ir.. The central ray is perpendicular to mid femur, centered to include hip joint and a portion of distal femur.. Image-quality criteria include proximal two-thirds of femur including hip joint visible., femoral neck shown in profile without foreshortening.. Standard exposure ranges from 75 to 85 kVp, 12 to 20 mAs, at an SID of 40 inches (102 cm).
Anatomy demonstrated
- Femoral head and neck in profile.
- Greater and lesser trochanters.
- Proximal two-thirds of the femoral shaft.
- Acetabulum and hip joint space.
- Intertrochanteric crest and line.
Patient preparation
- Verify patient identity using two identifiers.
- Remove radiopaque items from the pelvic and femur region.
- Position patient supine with both legs extended.
- Internally rotate the affected leg 15-20 degrees.
- Place a sandbag against the foot to prevent rotation.
- Confirm pregnancy status when applicable.
Position & centering point
Midway between hip and knee on the affected femur. Include the hip joint on the IR.
Central ray
Perpendicular to mid femur, centered to include hip joint and a portion of distal femur.
Exposure / technique
- kVp
- 75–85
- mAs
- 12–20
- SID
- 40" (102 cm)
- Notes
- Grid required. 14"x17" lengthwise IR.
Image-quality criteria
- Proximal two-thirds of femur including hip joint visible.
- Femoral neck shown in profile without foreshortening.
- Greater trochanter seen in profile lateral to the femoral neck.
- Lesser trochanter not seen or seen only slightly.
- No rotation of the proximal femur or pelvis.
- Soft tissues and trabecular pattern clearly demonstrated.
Common errors / ARRT traps
- 1 External rotation of the leg foreshortens the femoral neck.
- 2 Failure to include the hip joint on the receptor.
- 3 Insufficient internal rotation hides the greater trochanter.
- 4 Improper centering clips the proximal femur.
Clinical indications
- Suspected proximal femur or hip fracture.
- Evaluation of femoral neck pathology or stress reaction.
- Post-surgical follow-up of hip hardware.
- Assessment of bone lesions in the proximal femur.
Aligned to the 2025 ARRT Content Specifications.