Transarticular fixation of C1 and C2 according to the Magerl-technique is a delicate operation, with some risks for the vertebral artery. In the context of the Brite-Euram project PISA, a clinical trial with a medical image (high precision 3D-CT scan) based, personalized template with drill guide was carried out. The template is placed on the spinous process and lamina of C2 as well as on the posterior arch of C1, and the drill guide indicates the correct orientation of the drill holes at both sides. The results suggest that the template with drill guide may provide an accurate. per-operative indication of the drill holes into the cervical vertebrae as well as a cost effective alternative to the use of frameless stereotactic image guided surgery for this type of applications. During a pilot study with this kind of surgery on 2 patients some minor problems were encountered with the application of the template at C1 and C2 in the second case. Some adaptations to the technique will be tried out in the future.