Classification Description Notes
Type I <3mm anterolisthesis, no angulation Axial load, hyperextension
Type II >3mm anterolisthesis, angulation; disruption of posterior longitudinal ligament Hyperextension-axial loading force associated with severe flexion
Type IIa Horizontal fracture line; angulation without anterolithesis Flexion, distraction; mild or no displacement but very severe angulation
Type III Type I with bilateral facet joint dislocation Flexion, compression



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