Presentation
Incidental finding
From the case:
Accessory ossicle of the anterior arch of the atlas
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The abnormality depicted is well corticated and appears to articulate with the inferior aspect of the anterior arch of the atlas.
From the case:
Accessory ossicle of the anterior arch of the atlas
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Accessory ossicle of the anterior arch of the atlas.
Case Discussion
Features compatible with accessory ossicle of the anterior arch of the atlas. This is a rare normal variant and should be DDXed with calcific tendinitis of the longus colli muscles.