Atlanto-occipital dislocation

There is a dislocation of the occipital condyles (left(left and right) ventrally on the C1 lateral masses. There is significant prevertebral oedema from the skull base through C4. Additional soft tissue stranding and oedema are seen in the right lateral neck and along the left scalene musculature, which is also concerning for sequelae of trauma and soft tissue injury.There is soft tissue density dorsal to the thecal sac at the C1-C2 level concerning oedema and/or epidural haematoma with possible ligamentous injury. There is a widening of the dorsal interspace between C1 and C2.There is congenital nonunion of the posterior arch of C1.There are mild to moderate degenerative changes of the cervical spine, most pronounced at C4-C5 and C5-C6. No significant osseous canal stenosis is evident on non-contrast CT, but further assessment is recommended given the injury noted above.There is a minimally displaced fracture of the posterior aspect of the medial left T1 rib.