Bilateral facet dislocations in the thoracolumbar spine.

Bilateral facet dislocation represents approximately 11% of all thoracolumbar spine injuries requiring surgical stabilization. The injury can be caused by either flexion distraction (29/30 cases) or by pure distraction (1/30). Recognition of the injury is possible on plain radiographs, and confirmed by the empty facet sign on the computed tomography (CT) scan. In contradistinction to other major spine injuries, the majority of patients present with complete neurologic lesions (21/30). Recovery of patients with incomplete lesions is frequent (5/6); however, recovery from complete lesions did not occur. Compression instrumentation is recommended for patients with complete lesions because it is stable and requires no external immobilization. Distraction instrumentation that imparts significant extension is advised for patients with incomplete lesions. It is safe and reliable, and eliminates the posterior bulging of the injured disc that can occur with compression. For low lumbar injuries where compression is desirable in order to achieve the shortest possible instrumentation, a discectomy is recommended.