For an AP projection of the hip with accurate positioning,
1)the ASISs are positioned at equal distances from the IR.
2)the patient’s legs are externally rotated until the epicondyles are at a 45-degree angle with the imaging table.
3)gonadal shielding should not be used.
4)the central ray is centered 1.5 inches (4 cm) distal to the midpoint between the ASIS and symphysis pubis to center the hip joint in the field.