Fig. 3

Relationship of position between the most secure operating center point and the osseous anatomical landmarks at L1-L5. (A. Central point of the ipsilateral pedicle of the superior vertebral body at intervertebral space; B. central point of the ipsilateral pedicle of the inferior vertebral body at intervertebral space; C. the intersection of the horizontal line of the point “O” and the line segment “AB”; O. the most secure operating center point during the PETLIF procedures.)