A 20-year-old man was returning from a “night on the
town” when he drove his car into a garbage truck.
On arrival in the ED, the patient appeared intoxicated. He was
hemodynamically stable. He had a forehead contusion. The neurological
examination was normal, as was examination of the chest, abdomen
His lateral cervical spine radiograph is shown in Figure 1.
- Are there any abnormalities?
The initial lateral view was interpreted as negative for an acute
injury. However, the inferior portion of C7 was not seen. In addition,
the patient’s positioning was rotated; the left and right
lateral masses are widely separated.
The patient was maintained in spinal immobilization and the lateral
view was repeated with greater traction on the patient’s
arms (Figure 2).
Although this second view did not show C7, the injury is now
more easily seen. The injury, however, was visible on the initial
The second lateral radiograph more clearly reveals the patient’s
injury, although the injury was, in fact, visible on the first lateral
Although a definite fracture is difficult to detect, there is
indirect evidence that a fracture is present, i.e., malalignment of the upper cervical
spine. The C2 vertebral body shows
slight anterior displacement (anterolisthesis)
relative to C3 (asterisk in Figures 3 and 4). This displacement is easier to see in the second radiograph
Slight anterior displacement of the C2 vertebral body relative
to C3 may be normal, especially with supine cross-table lateral
radiographs in which the neck is slightly flexed. However, a second radiographic finding indicates
that this C2 anterolisthesis is abnormal.
The spinous process of C2 is displaced slightly posteriorly.
This is determined by drawing a line through the C1–C3
spinolaminar junctions: the posterior cervical
line (PCL) (lines in Figures 3, 4, and 5). Normally, the C1, C2, C3 spinolaminar junctions are within
2 mm of a straight line. In this patient, the C2 spinolaminar junction
is displaced 3 mm posterior to the PCL (arrowheads in Figures 3 and 4). Because the anterior
part of C2 is displaced anteriorly, and the posterior part of C2
is displaced posteriorly, the neural arch of C2 must be fractured.