Talocalcaneal coalition

Case contributed by Dr Jeremy Jones


Left ankle pain following sport and general activity.

Patient Data

Age: 12 years
Gender: Male

On the lateral view of the left ankle, there is a complete C sign between the posterior calcaneus and sustentaculum tali consistent with coalition.


There is irregularity of the talocalcaneal joint on the left suggestive of fibrous coalition.  No bony bar.

Annotated image

The normal right sustentaculum tali and left with its osseuous continuity with the talus demonstrated.

Case Discussion

The commonest of the tarsal coalitions is talocalcaneal coalition and is demonstrated by the continuous C sign on a lateral ankle radiograph.  They may be bony, cartilagenous or fibrous.

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Case information

rID: 23621
Published: 28th Jun 2013
Last edited: 14th Aug 2019
Inclusion in quiz mode: Included

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