Ventral ramus of spinal nerve
In the thoracic region they remain distinct from each other and each innervates a narrow strip of muscle and skin along the sides, chest, ribs, and abdominal wall.One advantage to having plexes is that damage to a single spinal nerve will not completely paralyze a limb.The lumbar and sacral plexuses innervate the pelvic girdle and lower limbs.Ventral rami, including the sinuvertebral nerve branches, also supply structures anterior to the facet joint, including the vertebral bodies, the discs and their ligaments, and joins other spinal nerves to form the lumbosacral plexus.This article incorporates text in the public domain from page 925 of the 20th edition of Gray's Anatomy (1918)