When performing a calcaneus exam in the plantodorsal (axial) position, the foot is positioned how?

When performing a calcaneus exam in the plantodorsal (axial) position, the foot is positioned how?

• A. Flexed at a 90 angle to the tibia/fibula with toes pointing up
• B. Placed in the lateral position with the foot flexed at 90 to the tibia/fibula
• C. Placed in the AP position with the plantar portion of the foot against the film
• D. Extended at an angle of 30 to the tibia/fibula

Answer: (A)

In the plantodorsal axial calcaneus view, you want the foot to be dorsiflexed so the plantar surface forms about a right angle with the tibia. This positions the calcaneus along its long axis and allows the beam to pass axially through the calcaneus when you angle the tube cephalad (typically about 40 degrees). The toes pointing upward indicate this dorsiflexed position, which helps prevent foreshortening and overlapping of structures so the calcaneal body and tuberosity are seen clearly. If the foot were in a lateral or standard AP position, or if the ankle weren’t at roughly 90 degrees to the leg, the axial projection wouldn’t align properly and the image would be less diagnostic.

In the plantodorsal axial calcaneus view, you want the foot to be dorsiflexed so the plantar surface forms about a right angle with the tibia. This positions the calcaneus along its long axis and allows the beam to pass axially through the calcaneus when you angle the tube cephalad (typically about 40 degrees). The toes pointing upward indicate this dorsiflexed position, which helps prevent foreshortening and overlapping of structures so the calcaneal body and tuberosity are seen clearly. If the foot were in a lateral or standard AP position, or if the ankle weren’t at roughly 90 degrees to the leg, the axial projection wouldn’t align properly and the image would be less diagnostic.