System for Reading Ankle Xrays

There are many ways to do this. If it doesn’t work for you. That’s fine! Develop a system that does work. Take this one and make it better. Always be on the look out for being more efficient and making things better.

System for Reading Ankle Xrays

  • Verify correct patient and image date

    • I’ve seen scenarios where it would have saved hours of time to just look for old images in the medical record to see if a problem was chronic before just jumping in and trying to fix something that is chronic and can’t really be fixed with a reduction.

  • Say what views your are looking at (AP, Lateral, Oblique)

    • If you aren’t sure, just say 3 views of a Left vs. Right ankle… for example

  • Skeletally mature or immature?

  • Look for obvious injuries and comment on them. Use the most straightforward and correct answer.

    • Don’t jump into the details right away

  • Example: AP, lateral and mortise view of a right ankle in a skeletally mature individual with an ankle fracture dislocation…

  • After you have established the obvious. Go back and systematically go through the images in each view

  • As always, it is helpful to start looking proximally and work your way distal

  • AP view

    • Outline the tibia and fibula looking for fracture lines

    • Look in medullary canals

    • Overlap of fibula and tibia is >6mm

    • Visualize ankle joint space and that there is equal clear space across the ankle joint on all sides, the medial, lateral and plafond.

    • Look at the length of the fibula, check “Dime sign” 

      • In the image below there is medial clear space widening, the dime sign is off slightly, but is relatively close to where the tip of the lateral malleolus lines up with the talus. If the fibula was short, it would not touch the top of the dime.

    • Soft tissue review proximal to distal

The picture above shows what a short fibula would look like, the dime sign would be abnormal.

Source: Journal of Foot and Ankle Surgery

  • Lateral View

    • Check image quality

      • Posterior fibula border is overlapping within a ⅓ of the posterior tibial border

        • In the image below, the posterior fibula border is almost perfectly lined up

    • Medial and lateral talar dome lines are lined up to create a perfect semicircle at the tibiofibular joint


    • Outline tibia, fibula, and medullary canals 

    • Review tibiotalar joint space, talus centered on tibia

    • Review talus body and outline

    • Talar-navicular joint

    • Subtalar-joint

    • Calcaneus body and outline

    • Cuboid outline

    • Soft tissue

  • Mortise View

    • Check quality: Medial and lateral malleoli are in profile, which means the anterior edge is perfectly lined up with the posterior edge

      • Best seen on the medial malleolus

    • Proximal to distal bone outline and medullary canals

    • Check syndesmosis

      • Tibia / fibula overlap >1mm on mortise view

    • Review Soft Tissue


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