Bilateral facet dislocation

A bilateral facet dislocation is an unstable flexion distraction type of dislocation of the cervical spine, often a result of buckling force. Occasionally, the bilateral facet dislocation has been named a 'doubly-locked' vertebral injury giving the impression of stability. However, due to complete ligamentous disruption, this is, in fact, an unstable injury .

Pathology

Mechanism

It has been thought to result from hyperflexion, however, recent studies suggest a buckling force to be the cause .

Radiographic features

• loss of apposition at facet joint: bilateral facet joints may be perched or locked
• anterolisthesis can be more than 50%
  • if there is a lesser amount of displacement one of the facet joints may be intact (unilateral facet joint dislocation)
• increased interspinous distance