On the basis of a computed tomography, the surgeon plans the entry points, the screw size and length, as well as the angle of the screws in two planes (sagittal and axial) on the computer. In the MySpine group, a three-dimensional, digital reconstruction of the spine is made using Medacta International SA software. On the basis of these planning files, three-dimensional templates with guide channels (guides) are produced for each individual vertebra. These guides can be applied dorsally to the bony anatomy and thus specify the entry points as well as the direction of the screw. Also, replicas of the individual vertebra are produced in the 3D printer.