The Relationship between the Superior Gluteal Artery and Lumbosacral Plexus

Background: The internal iliac artery has been shown to branch with great variability. As the superior gluteal artery leaves the pelvic cavity through the greater sciatic foramen it travels around the roots of the lumbosacral plexus, often compressing underlying nerves. Knowledge of the variability with which the superior gluteal artery passes around the roots of the lumbosacral plexus is clinically important. The information may help physicians better understand how the superior gluteal artery can compress roots of the lumbosacral plexus. Methods: 112 adult human pelvic halves were procured from cadavers for this study. Results: The Superior Gluteal Artery (SGA) was found to take four different pathways through the lumbosacral plexus. The most common path taken by the SGA was between the Lumbosacral Trunk (LST) and anterior ramus of spinal nerve S1. This occurred in 76 of the 112 specimens (67.9%). The second most common path taken by the SGA was lateral to (outside of) the LST. This occurred in 23 of the 112 specimens (20.5%). The third most common route taken by the SGA was between the L4 and L5 part of the LST. This occurred in 11 of the 112 specimens (9.8%). The least common course of the SGA was between the anterior rami of spinal nerves S1 and S2. This was observed in 2 of the 112 specimens (1.8%). In most cases, either the superior gluteal artery or posterior division of the internal iliac artery passes firmly over the surface of one of the nerve roots of the lumbosacral plexus.