Lateral Proximal Femur is a radiography positioning projection of the Lower Extremity. Lateral recumbent on affected side. Hip joint included. The centering point is located midpoint of the IR (Bontrager); midfemur and center of the IR (Merrill's). Hip joint must be included. The central ray is perpendicular to the femur, to the midpoint of the IR; adjust the IR to include the hip joint. Image-quality criteria include proximal two-thirds of femur including hip joint visible, most of the greater trochanter superimposed by the femoral neck. A sample technique is 87.5 kVp with DR 7.1 or CR 14 mAs, at an SID of 40 inches (102 cm).
Anatomy demonstrated
- Femoral head and neck in lateral profile.
- Greater trochanter superimposed over femoral neck.
- Lesser trochanter, mostly superimposed by the femur.
- Proximal two-thirds of the femoral shaft.
- Acetabulum and hip joint.
Patient preparation
- Verify patient identity using two identifiers.
- Remove radiopaque items from the pelvic and femur region.
- Position patient in lateral recumbent on the affected side.
- WARNING: do not use this position if a hip or proximal femur fracture is possible (Bontrager), or with any femoral fracture or possible destructive disease (Merrill's). Use the trauma lateral hip routine or a horizontal-beam lateral.
- Flex the affected knee about 45 degrees and center the femur to the table.
- Extend the unaffected leg behind the affected knee, support it, and roll the patient back about 15 degrees.
- Place the upper IR margin at the level of the ASIS.
- Confirm pregnancy status when applicable.
- Collimate closely. Bontrager still says to shield outside the region of interest; Merrill's reports that NCRP Statement No. 13 recommends ending routine gonadal shielding in abdominal and pelvic radiography, and AAPM also limits routine shielding. Follow your department's policy.
Position & centering point
Midpoint of the IR (Bontrager); midfemur and center of the IR (Merrill's). Hip joint must be included.
Central ray
Perpendicular to the femur, to the midpoint of the IR; adjust the IR to include the hip joint.
Exposure / technique
- kVp
- 87.5
- mAs
- DR 7.1 / CR 14
- SID
- 40" (102 cm)
- Notes
- Grid required. 14"x17" lengthwise IR. Trauma patients may need cross-table lateral. Bontrager prints digital 80 +/- 5 kV; the sample is Merrill's chart. Sample technique: DR 7.1 / CR 14 mAs at 87.5 kVp, 40 in SID, for a 19 cm part. Adjust for your equipment.
kVp and mAs are sample values. Use caution when applying them in your department.
Image-quality criteria
- Proximal two-thirds of femur including hip joint visible.
- Most of the greater trochanter superimposed by the femoral neck.
- Trochanters largely superimposed by the femur; only a small part shows medially.
- Soft tissues and trabecular pattern clearly demonstrated.
- No superimposition of unaffected leg over the proximal femur.
Common errors
- 1 Unaffected leg superimposed over the proximal femur.
- 2 Failure to include the hip joint on the receptor.
- 3 Patient not rolled back about 15 degrees, superimposing the proximal femur and hip joint.
Clinical indications
- Mid- and proximal femur including lateral hip, for fractures and bone lesions.
- Not for a possible hip or proximal femur fracture (Bontrager), or any femoral fracture or destructive disease (Merrill's): use the trauma lateral hip routine or a horizontal-beam lateral.