Superior Hypogastric Plexus Block: Anatomical Considerations

The superior hypogastric plexus (SHP) block has been shown to provide benefit in treating visceral pelvic pain in malignant and non-malignant conditions.1,2 The block is classically performed by targeting the anterior portion of the L5 vertebral body using fluoroscopy or computed tomography (CT) guidance.1 These images portray common iliac vein contrast uptake, a known complication of the procedure.3 Figure 1 demonstrates the initial trajectory in the ipsilateral oblique (A) and lateral views (B). Vascular spread into the common iliac vein is identified (C), with washout seen on subsequent imaging (D). The needle was repositioned caudally at the inferior border of the L5 vertebral body with appropriate spread of contrast identified (E and F). When performing the SHP block, an effort is made to maintain contact with the vertebral body while advancing to the presacral space. This may be facilitated with a distal bend in the needle and a lateral-to-medial approach. Although effort may be undertaken to maintain contact with the vertebral body, practitioners may drift away from the bone along the anterior aspect due to the vertebral body’s circular shape and variable anatomy. In this case, a distal bend of the needle was utilized, but a more lateral approach was limited due to the patient’s iliac crest. These images demonstrate the importance of maintaining contact with the vertebral body, as the common iliac vein may lie millimeters away, demonstrated in Figure 2(A) of a CT scan of the abdomen and pelvis of the same patient.