In the year 1981, J. Böhler completed for the first time a screw fixation for unstable fractures of the odontoid process of the axis. This surgical technique preserves the anatomy and the physiology of the articulation between the atlas and the axis, as a guarantee for a good functional recovery. It is not a very difficult technique when performed by a trained surgeon with a very good X-ray image intensification for the per-operative control. We have treated 32 unstable fractures of the odontoid process without any neurological complication per- or post-operatively. We had a follow-up on only 29 cases. In 19 cases the fracture healed in leading to a good bone union, complete mobility and no residual pain. Seven patients complained of residual pain or a limitation in cervical movement, because of the association with other cervical fractures, an age superior of 70 years, or a major initial instability. In 2 cases the authors noted a non-union and a secondary displacement because of technical faults at the beginning of their experience. These good results determined the authors to prefer the direct screw fixation for the unstable fractures of the odontoid process, to the posterior arthrodesis which leads to functional limitations.