Description of the perineal pelvic innervation

Perineal pelvic innervation by somatic nerves includes:

• The genitocrural nerve and the iliohypogastric nerve from levels D12-L1-L2,
• The cluneal (or lesser sciatic) nerve coming from L4-L5-S1 and
• The pudendal nerve (pudendal nerve) coming from the sacral roots (S2-S3-S4).

Perineal pelvic innervation by the autonomic nervous system is divided into:

• A mixed system: the lower hypogastric plexus formed by
• • the union hypogastric nerves coming from the superior hypogastric plexus itself formed by sympathetic thoraco-lumbar afferents (D12-L1-L2) and
  • the pelvic (parasympathetic) splanchnic nerves from S2-S3-S4.

The pelvic floor muscles are innervated by the somatic roots from L5 to S5.

pelvic innervation schema

Superficial perineal pelvic innervation (diagram )

In men and women:

• in yellow: the cluneal or lesser sciatic nerve (lower lumbar roots)
• in red: the pudendal nerve (sacral roots)
• in blue: the ilioinguinal and genitocrural nerves (upper lumbar roots)