Unilateral thoracic facet dislocation.

A unilateral facet dislocation is an injury classically localized to the cervical spine. A series of 3 unilateral thoracic facet dislocations are reported in 2 adults and 1 child. Each had severe concomitant injuries to the thorax, which caused respiratory compromise. On lateral radiographs, all had anterior vertebral body translation of less than 20% of the vertebral body width with minor degrees of kyphosis. Axial computed tomographic images showed a unilateral empty facet sign. All patients were neurologically intact and none had any mechanical pain at last followup. The mechanism of injury is flexion distraction with rotational force that disrupts the rib cage.