Os trigonum

Case contributed by Dr Bruno Di Muzio


Trauma history.

Patient Data

Age: 19
Gender: Female

Left ankle X-ray

Os trigonum is present. Signs of posterior joint effusion are also noted. 

Annotated image

Os trigonum is delineated. 

Case Discussion

Os trigonum is one of the bony ossicles of the foot and can be mistaken for a fracture. It sits posterior to the talus on the lateral foot radiograph and represents failure of fusion of the lateral tubercle.

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Case information

rID: 39455
Published: 5th Sep 2015
Last edited: 14th Aug 2019
Inclusion in quiz mode: Included

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