Ankle X-Ray AP

Lower Limbs Anteroposterior STD
Objective

Malleoli and tibiotalar mortise.

Positioning

Patient supine with ankle on the detector.
Foot in slight internal rotation of 10–15° to bring the tibiotalar mortise into true AP projection (malleoli equidistant from the detector).
Central ray: perpendicular to the IR.

Centering

Tibiotalar joint

DR Parameters

60–70 kV · 5–8 mAs
SID ~100–115 cm · no grid

CR Parameters

60–70 kV · 8–12 mAs · SID ~100–115 cm

Quality criteria

Malleoli visible.
Tibiotalar mortise visible.
No rotation.

Common errors

Ankle rotation.
Incorrect centring.
Movement.

Practical notes

Check for metallic objects.
Always mark the examined side (R/L) before exposure.