Hangman's fracture is a fracture of which cervical veebra?

Traditionally considered a hyperextension/distraction injury from placement of the noose under the angle of the jaw, hangman's fractures also may occur with hyperextension/ compression, as with diving accidents, or hyperflexion. The injury is defined by bilateral C2 pars interaicularis fractures. The pars interaicularis is the bone between superior and inferior facet joints. Thus, the posterior bony connection between C1 and C3 is lost. Ref: Schwaz's principle of surgery 9th edition, chapter 42.