Anterior Screw Fixation of Dens Fracutre

Chung, Jae Yoon; Jung, Sung Taek

Abstract

The treatment of fractures of the dens is controversial and the major controversy has centered on type II fracture of Anderson and D'Alonzo classification because of its high incidence of nonunion when they were treated by external immobilization like halo apparatus. The posterior arthrodesis of atlas and axis which has been recommended by many authors results in the limitation of rotation of neck. In an attempt to promote bone union and to eliminate functional impairment, the authors have treated 7 consecutive cases of type II dens fracture by direct screw fixation with one or two screws. Minimum follow up period was 15 months(Av. 20mos.). Ages were varied between 23 to 68 years. Amounts of displacement on arrival were more than 4mm in all. Ambulation was started from the day after operation with the external support. Bone union was observed in 6 cases within 3 months without limitation of rotation. One nonunion with losening of screw and one transient dysphagia were observed. The authors believe that the procedure has the advantages in bone union and neck motion, but it requires surgeon's experience and the modification of implant for secure fixation.