Table 1.

Denis Classification (modified) used for categorization of thoracolumbar spine injury

Minor Injuries Isolated fractures of transverse process/facet/pars/spinous process

Major Injuries Compression Fractures: Compression injury involving anterior column Burst Fractures: Compression injury involving anterior and middle columns ◦ Stable burst fractures: Posterior ligamentous complex intact ◦ Unstable burst fractures: Posterior ligamentous complex injured/disrupted Flexion-Distraction Injuries: Distraction injury of posterior and middle columns; Anterior column may fail in compression or distraction ◦ Chance fracture (bony) or variant (ligamentous): Anterior column fails in distraction ◦ Flexion-distraction with anterior column compression: Posterior and middle columns distract, while the anterior column fails in compression Fracture-Dislocations: All three columns injured ◦ Flexion-rotation, ◦ Shear, and ◦ Flexion-Distraction mechanisms Extension injuries: Distraction injury of Anterior Column; Middle Column may or may not have distraction failure ◦ Extension-distraction: Anterior column opening through disc, vertebral body, or combination thereof; Middle column intact (no posterior annular disruption, no retrolisthesis) ◦ Extension injury with middle column injury Middle column disrupted in extension with angulation alone Middle column disrupted in extension with angulation and / or translation