L4 L5 L4 and L5 merge to form the lumbosacral trunk S1 S2 S3 L4, L5, S1, S2, S3 forms the sciatic nerve and other combinations form the superior and inferior gluteal S4 S2, S3, S4 join to form the pudendal nerve that supplies structures in the perineum. The inferior mesenteric plexus starts out in the abdomen at the point of origin of the inferior mesenteric artery and passes along the aorta to the presacral region. As the plexus drops into the pelvis, it usually splits up into a right and left hypogastric plexus that lies behind the rectum. The sacral sympathetic chain is the continuation of the lumbar chain. The sacral part of the parasympathetic nervous system arises from S2, S3, S4 and supplies the pelvic structures as well as the left colic flexure, descending colon and sigmoid colon.
Urinary bladder Compare the male and female bladders.
The prostate gland is a cone-shaped gland about the size of a chestnut and is made up of connective tissue and smooth muscle. Adenomas are frequent in this lobe and they encroach into the urethra, blocking the internal urethral orifice. The uterus is a midline organ and is held to the lateral walls of the true pelvis by a double layer of peritoneum, called the broad ligament . The broad ligament also encloses the uterine tube in its upper free border, the ovarian artery, the round ligament of the uterus, uterine artery, ovary, and the ovarian ligament. A better understanding of the relationships to the broad ligament can be gained if you also look at a section through the broad ligament.