© 2012 Must See Radiology

• History
• View Case
• Findings
• Diagnosis
• Check Out

• History
• View Case
• Findings
• Diagnosis
• Check Out

Key Image

CTA of the neck, sagittal and coronal bone level imaging centered over the cervical spine

Key Findings

Finding 1 demonstrates a unilateral dislocation of the C6 facet (red arrow). There is a fracture of the superior facet articulation of the C7 vertebral body as well (yellow arrow). Note normal facet articulation (white arrow).
Finding 2 demonstrates a fracture through the left occipital condyle (yellow circle). The fracture is anterior to the left jugular foramen and hypoglossal canal (not pictured).

• History
• View Case
• Findings
• Diagnosis
• Check Out

Diagnosis

Unilateral Facet Dislocation / Fracture
& Occipital Condyle Fracture

Discussion

Method of injury is forced flexion and rotation. Unilateral dislocations are stable, but bilateral dislocations are unstable. These are best demonstrated on the lateral and oblique radiograph / CT views. Anterior dislocation of the affected ody is usually less than half of the AP diameter of the vertebral body. See Primer of Diagnostic Imaging, 5th ed, page 274-275

Occipital Condyle Fractures:
These fractures are best viewed on coronal CT images. They can be subtle and overlooked. If large enough, they can involve the jugular foramen or hypoglossal canal. The jugular foramen contains the inferior petrosal sinus, sigmoid sinus, posterior meningeal artery and cranial nerves #9,10,11. The hypoglossal canal contains cranial nerves #12.

Remember... satisfaction of search is a thing. Don't do it. Learn a search pattern and stick with it, no matter what you find along the way!

References / Resources

Additional Information:

1. Dahnert*: 215
2. Primer*: #
3. Related Article:

   Scher AT "Unilateral Locked Facet in Cervical Spine Injuries." AJR 1977: 129 45-49.

• History
• View Case
• Findings
• Diagnosis
• Check Out

Feedback

Any feedback regarding this case can be emailed to Tony@mustseeradiology.com