Editorial Comment on: The Contribution of the Levator Ani Nerve and the Pudendal Nerve to the Innervation of the Levator Ani Muscles:.A Study in Human Fetuses

摘要

As a brief introduction about pelvic neuroanatomy, the somatic nerve supply to the pelvis comes from the lumbosacral plexus, which has two main origins: lumbar level and sacral level. Iliohypogastric, ilioinguinal, genitofemoral, femoral, and obturator nerves arise above from lumbar level L5. However, the lumbosacral trunk consists of the nerves from the L4-5 and S2-4 levels. Pelvic branches from the sacral nerve include (1) the posterior femoral cutaneous nerve, (2) the pudendal nerve (S2-4), (3) the nervi erigentes (pelvic splanchnic nerve) (S2-4) to the autonomic plexus, and (4) the pelvic somatic efferent nerves, which give branches to the levator ani. The parasympathetic autonomic nerve supply is given by nervi erigentes (S2-4) with a contribution from the hypogastric nerves arising from the sympathetic superior hypogastric plexus and branches of the sacral sympathetic ganglia from the inferior hypogastric (pelvic) plexus . Classically, somatic nerves are below the endopelvic fascia (extrapel-vic)and autonomic nerves are above the fascia (intrapelvic). There have been many issues about urethral sphincteric control and its possible dual innervation. It was suggested that there was an intrapelvic somatic nerve originating from S2-4 , or a fascia traversing branch from the dorsal nerve of penis/clitoris . Recently, it was shown that a traversing branch of the pudendal nerve innervates the urethral sphincter at a different level than the autonomic nerve innervation point .