Fig. 3.

(A) C-arm oblique orientation using a coaxial method for needle placement. The oblique angle can be obtained according to the preoperative planning. (B) Zoomed image of oblique projection and its relationship with the rib head (blue dotted circle) and the pedicle (white dotted circle). The zone marked in yellow is the safest zone for docking the needle and always has to be centered in the disc complex. (C) C-arm oblique projection of the previous image. Note the safety point in between the rib head and the shadow of the pedicle, as described in panel B.