BIOMECHANICS OF ODONTOID FRACTURE FIXATION - COMPARISON OF THE ONE-SCREW AND 2-SCREW TECHNIQUE

Direct anterior screw fixation of odontoid fractures has become more p revalent clinically. No biomechanical study, however, has determined w hether one or two screws should be used. This study measured the stabi lity of the odontoid process after fracture and internal fixation with one or two screws. Internal fixation of Type II odontoid fractures di d not restore the original stability of the intact specimen, direct in ternal fixation with one or two screws provided 50% of the stability o f the unfractured odontoid, and no significant differences between the one- and two-screw technique was found under loading to failure, alth ough the two-screw technique provided increased stiffness in extension loading.