A lateral cervical spine radiograph shows grade I anterolisthesis of C2 on C3 (arrow) with fractures of the C2 pars interarticulares (arrowheads).
- Traumatic spondylolisthesis of C2
- Combination of soft tissue and bony injuries believed to start from anterior longitudinal ligament (ALL) tear, avulsion of C2/3 disc from either inferior or superior endplate - then bony malignment and posterior element fractures.
- Posterior element fractures are often extra-articular, involving the pars interarticulares (pedicles)
- Named "hangman" because of mechanism of injuries mimic that of hanging (neck hyperextension with compression of posterior elements)
- Displaced fractures often are associated with neurologic injuries (apnea, complete paralysis, sensory loss distal to lesion)
Mandavia DP, Newton EJ, Demetriades D. Color Atlas of Emergency Trauma, 2003.