Anatomic and Biomechanical Study to Guide in the Choice of Atlantoaxial Fixation Pattern

Placing posterior atlas screws is technically demanding, and a misplaced screw can result in serious medical consequences. However, the current surgical approach and choice of internal fixation technique are usually decided according to the doctor’s personal experience and preferences. The purpose of this paper was to set up an integrated solution for screw placement of posterior atlas fixation, using 3D interactive visualization anatomic measurement and biomechanical simulation analysis. The atlas posterior arch screw demonstrated the lowest risk factor for damaging nearby tissues. The three mainstream posterior internal fixations can provide similar stability for the odontoid fractures. Atlas pedicle screw generated the lowest stresses on screws showing it stabilizing capability. The three fixations have the ability to offer enough stability for atlantoaxial instability caused by odontoid fractures, and each with its own set of merits and demerits. The results of this study can serve as process for customized surgical planning.