Aim:The atlanto-axial complex is usually stabilized by a posterior transarticular screw placement (Magerl) or thru a posterior internal fixator according to Goel/Harms. For atypical anatomy there are possible alternative screw pathways in C2. These alternatives include the use of intralaminar screws, pars interarticularis screws or anterior transarticular screws.Material and Methods:Eight human cervical spines (segments C0-C3) were tested in flexion/extension, lateral bending and axial rotation. Range of Motion (ROM) at a 1.5 Nm load was recorded. After native testing, the Harms (HARMS), pars screw (PARS), intralaminar screw (INTRA) and anterior transarticular screw (ATA) constructs were applied in a random order. Results:All instrumentation techniques were able to reduce ROM for most of the motions. The differences between the techniques were small. Nevertheless, the intralaminar screw showed deficits in lateral bending. Conclusion:Screw positioning seems to be of minor influence on stability in atlantoaxial stabilization. Therefore, the pars screw is a sound alternative to the established techniques from a biomechanical point of view. Anatomical considerations for screw placement should be kept in mind as a superior priority.