Imaging Case of the Week 52

The following ankle x-rays are from a 62 year old male who was involved in a high speed MVA. His ankle is quite swollen. What can you see?


Ankle AP

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Ankle mortise

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Ankle lateral

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Here are the magnified views:

Ankle magnified

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Magnified lateral

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The AP view of the ankle shows a bony fragment with irregular edges medial to the talus.

The mortise view shows talar neck fracture. There is a cortical break involving the medial margin of the talar neck along with sclerosis, which indicates a degree of impaction.

The lateral view shows small fracture fragments posterior to the talus.

Here’s the ankle CT slice:

Ankle CT

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The Hawkin’s classification of talar neck fractures:

  • Type I – non displaced fracture of talar neck without dislocation.
  • Type II – displaced fracture of the talar neck with subluxation or dislocation of the subtalar joint.
  • Type III – displaced fracture of the talar neck, with the dislocation of the body of the talus from the subtalar and ankle joints.

This patient has a type II injury.

Undisplaced talar neck fractures are easy to miss and the main complication of such a fracture is avascular necrosis.

Thanks to Dr. Rafal Francikiewicz for the images.