Fig. 6

Positional consistency between planning and guidewire/screw. The planning is demonstrated as two red dots indicating the entry point and the end point of the screw. The diameter of the dots is 2.5 mm. The positions of the guidewires could be accurate (A) or deviated (B, C). A deviated guidewire can result in an accurate screw when compared to the planning, under the positive guide effect from the pedicle wall (D)