AP pelvis

Patient position

• Supine, MSP centred to the table; arms away from the pelvis.
• ASISs equidistant from the tabletop (no rotation).
• Both legs internally rotated 15–20° (feet together at the toes, heels apart) — unless a hip fracture is suspected.

Centering

MSP, midway between the level of the ASISs and the symphysis pubis — about 5 cm (2″) below the ASIS level.

Central ray

Perpendicular to the IR.

Source-to-image distance

100 cm (40″).

Image evaluation

• Lesser trochanters not (or only just) visible
• Femoral necks in full length, greater trochanters in profile
• Symmetric iliac wings and obturator foramina
• Coccyx in line with the symphysis