Accessory Ossicle of the Anterior Arch of the Atlas

Description

Lateral CT at the level of C1 showing inferior accessory ossicle of the anterior arch of atlas (white arrow). Fig.3. T1 GD enhance MR image showing no definite evidence of hematoma and soft tissue swelling at the level of C1

Name

• Accessory Ossicle of the Anterior Arch of the Atlas
• Os avis
• Accessory ossicle of C1 anterior arch
• Anterior atlas ossicle
• Anterior arch ossicle of C1
• C1 accessory bone

General

• Normal variant of the anterior arch of Atlas
• Best appreciated on lateral cervical or sagittal study
• Appears as a circular and corticated osseous density
• Articulates with inferior aspect of the anterior arch
• Generally asymptomatic and incidental finding
• One of the accessory bones of the spine

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Clinical Significance

• Needs to be updated

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See Also

• Accessory Bones Main
• Radiology Main
• Cervical Spine Anatomy

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