Two patients present to the ER after MVA's in which they suffered multiple injuries. Both patients were reported to have struck the windshield and suffered LOC with scalp lacerations. Both patients received C-spine evaluation for injuries prior to removal of C-spine collars.

Radiologic Findings:
Patient A:
Lateral C-spine shows anterior displacement of C-1 anterior vertebral body line, posterior vert body line, spinolaminal line, and spinous process line. There is also a comminuted fracture visible in the anterior aspect of C-1.

Odontoid view shows lateral displacement of both C-1 lateral masses.

Patient B:
Lateral C-spine shows posterior shift of ant and post vertebral body lines and fracture through lamina and pedicles of C-2. Anterior view shows lateral deviation of atlantoaxial line.

CT shows fracture of post arch of C-2.

Discussion:

In 1920 Sir Geoffrey Jefferson described the mechanism for fracture of C-1. This fracture is a burst type fracture produced by a severe compressive force transmitted directly through the lines of the vertebral body while the C-spine is held straight. Under these circumstances, both the ant and post bony elements of the vertebrae are crushed. This force is sufficient to crush the bony elements while the ant and post ligamentous structures remain intact. As long as the transverse ligament remains intact, the spinal cord may not be damaged. However, remember that all of these fractures are unstable and must be treated with immobilization.