Peg Fractures

Peg fractures are classified according to the Anderson and D’Alonzo system [16].

Type I Fractures involve the upper portion of the odontoid process only. These are stable injuries, but there is a risk of avascular necrosis.
Type II Fractures involve the base of the odontoid process. These are unstable injuries and usually require operative intervention.
Type III Injuries extend into the body of C2. These are stable injuries.