Benzel Classification:

Fractures of Axis-

- 1) odontoid fracture (55%)

- 2) Hangman's fracture (23%)

- 3) other C2 fractures - nonodontoid/nonhangman's fractures (22%)

Benzel Classification-

fractures of the C2 body between the base of the odontoid and the pars interarticularis-

- Type I: coronally oriented vertical fracture of the C2 body

- Type II: sagittally oriented vertical fracture of the C2 body - from axial loading

- Type III: horizontal rostral fracture of the C2 body - similar as type III odontoid fracture

Management-
External immobilization in the uncomplicated cases. Certain fractures with facet involvement or posterior element involvementare more unstable and need internal fixation with or without halo.

Anterior plate ascrew fixation is an option for type I Benzel fracture, Type II and III needs posterior approach. Due to disruption of the anterior versus posterior elements, a two-level fusion is indicated ( C1 through C3). If arch of C1 is not competent consider occiput to C3 fusion.