Which position is best for visualizing the entire ankle mortise?

Which position is best for visualizing the entire ankle mortise?

• A. 15° internal oblique ankle
• B. Lateral ankle projection
• C. AP ankle projection
• D. 30° external oblique ankle

Answer: (A)

The best position for visualizing the entire ankle mortise is the 15° internal oblique ankle projection. This specific oblique position allows for optimal visualization of the ankle joint, particularly the mortise area, which includes the joint space between the distal ends of the tibia and fibula and the talus.

In this position, the internal rotation opens up the mortise joint clearly, reducing superimposition over this crucial articulation. This is particularly important in radiological assessments for detecting fractures or other issues within the mortise area.

In contrast, the other projections do not provide the same level of clarity for the mortise view. The lateral ankle projection primarily shows the side profile of the ankle and may obscure the mortise joint. An AP ankle projection offers a frontal view but lacks the necessary obliquity to visualize the joint space effectively. Similarly, a 30° external oblique may rotate the ankle, but it does not adequately display the mortise in the same way an internal oblique does. Thus, the 15° internal oblique position is critical for a thorough examination of the entire ankle mortise.