How much should the patient's foot be rotated for an anteroposterior (AP) mortise ankle radiograph?

For an anteroposterior (AP) mortise ankle radiograph, the foot should be rotated approximately 15-20 degrees internally. This positioning is crucial because it allows for optimal visualization of the mortise joint, which is the area where the talus articulates with the tibia and fibula. The internal rotation opens up the joint space between the tibia and fibula, enabling assessment of potential fractures or other abnormalities that may not be visible without this angled view. By achieving this degree of rotation, healthcare professionals can obtain a clear and detailed image of the ankle's anatomy, which is essential for accurate diagnosis and treatment planning.