Anatomical Location of the Common Iliac Veins at the Level of the Sacrum: Relationship between Perforation Risk and the Trajectory Angle of the Screw

Figure 4

(a) Locations of the common iliac veins (CIVs) and inferior vena cava (IVC). The pin indicates the center of the promontorium. (b) The vertical arrow indicates the distance between the level of the IVC formation and tip of the promontorium. The horizontal arrow indicates the distance between the right and left CIVs. (c) The white arrow indicates the distance between the center of the promontorium and the medial wall of the right CIV (R-CIV), and the black arrow indicates the distance between the center of the promontorium and the medial wall of the left CIV (L-CIV).

(a)

(b)

(c)