J Korean Orthop Assoc.  2010 Jun;45(3):234-237. 10.4055/jkoa.2010.45.3.234.

Inferior Accessory Ossicle of the Anterior Arch of the Atlas

• Whang CS
• Chung PH
• Suh KJ
• Kang S
• Kim JP
• Kim YS
• Cho JW

• KMID: 2185524
• DOI: http://doi.org/10.4055/jkoa.2010.45.3.234

Abstract

An inferior accessory ossicle of the anterior arch of the atlas is quite rare and should not be confused with other pathological conditions such as a fracture. Here we report a case of an inferior accessory ossicle of the anterior arch of the atlas in a 29-year-old male and a review of literature.

Keyword

atlas; accessory ossicle

MeSH Terms

Adult
Humans
Male

Figure

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  Figure 1 Lateral cervical radiograph shows loss of cervical lordotic curvature and bone fragment inferior to the anterior arch of the atlas. There is no prevertebral soft tissue swelling.

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  Figure 2 Magnified image of the upper cervical spine shows a well corticated inferior accessory ossicle of the anterior arch of the atlas (arrow).

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  Figure 3 Sagittal CT image shows marginal sclerotic elliptical ossicle inferior to the anterior arch of the atlas.

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  Figure 4 Axial CT image shows the midline location of the inferior accessory ossicle of the anterior arch of the atlas.

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  Figure 5 3D CT image viewed from anterior aspect of the upper cervical spine shows the inferior accessory ossicle of the anterior arch of the atlas.

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  Figure 6 (A) Flexion and (B) extension lateral cervical radiographs show no motion of the inferior accessory ossicle of the anterior arch of the atlas.

Reference

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