Absence of the Lumbosacral Trunk.

The lumbosacral trunk, typically comprised of part of the fourth lumbar ventral rami and the entirety of the fifth lumbar ventral rami, serves as a connection between the lumbar and sacral plexuses. Developmental differences underlie the variable relative contributions of L4 and L5 to the lumbosacral trunk. Herein, we report a rare case in which dissection of an adult male cadaver revealed no L4 contribution to the lumbosacral plexus. We discuss the surgical and clinical implications of such an anatomic variation.
Competing Interests: The authors have declared that no competing interests exist.