To rule out a fracture of the dens, which X-ray view must be performed?

• A. Flexion-Extension
• B. Anterior-Posterior
• C. Lateral View
• D. Open Mouth

Answer: (D)

The open-mouth odontoid view is used to rule out a fracture of the dens. This view is specifically chosen because turning the mouth open moves the mandible out of the way and provides a direct projection of the odontoid process and the C1–C2 joint. It lets you clearly assess the alignment of the dens with the atlas and identify any fracture displacement that might be hidden on other views. Other views, like the lateral, anterior-posterior, or flexion-extension, can miss or be less reliable for visualizing the dens, or are more suited to assessing instability rather than a ductal fracture. If suspicion remains after radiographs, CT confirms the diagnosis with greater detail.