Hangman fracture involves fracture of which part of C2 with anterior displacement of C2?

• A. Pars interarticularis of C2 with anterior displacement of C2
• B. Dens of C2
• C. Body of C2
• D. Spinous process of C2

Answer: (A)

Hangman fracture is defined by a bilateral fracture through the pars interarticularis of the C2 vertebra (axis), which allows the vertebral body of C2 to slip forward on C3, producing anterior displacement. This pattern results from a hyperextension mechanism with axial loading in high-energy trauma. Fractures of the dens (odontoid) involve the tooth-like projection of C2 and are a different injury, not characteristically associated with forward slip of C2 on C3. A fracture of the body or a spinous process involves different structures and would not regularly cause the same anterior translation of C2 on C3. Thus, the hallmark of a Hangman fracture is a pars interarticularis fracture of C2 with anterior displacement of C2 relative to C3.