Atlantoaxial Subluxation due to an Os Odontoideum in an Achondroplastic Adult: Report of a Case and Review of the Literature

Figure 7

Sagittal reconstructed CT plus angiography, showing optimal alignment, and decompression of cervicomedullary junction achieved with C1 arch laminectomy and limited occipital laminectomy. Note shortness of clivus, low Trochlor Herophili, and low external occipital protuberance and integrity of the basilar artery.

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