Where is the CR directed when performing an AP projection of the ankle joint?

When performing an AP projection of the ankle joint, the central ray (CR) is directed perpendicular to a point midway between the malleoli, which are the two bony protrusions on either side of the ankle. Positioning the CR in this way ensures that the image captures the joint space accurately and that the entire anatomy is included in the radiograph without distortion. By targeting this midpoint, the radiograph effectively visualizes the ankle joint and facilitates assessment of any potential pathologies or fractures in a well-centered manner.

This method is important for obtaining a clear and diagnostic image of the ankle, as the midpoint between the malleoli represents the center of the ankle joint, allowing for proper alignment and exposure of the relevant structures. Inaccurate CR positioning could lead to poor image quality and could obscure important anatomical details necessary for diagnosis.