- Origin: Anterior Divisions of S2, S3 and S4 -Sacral plexus
- Passes back between Piriformis and Coccygeus medial to Pudendal vessels
- Appears between Piriformis and Sacrospinous Ligament in the buttock
- Curls around Sacrospinous Ligament to run forward into the Ischioanal Fossa
- Gives off the Inferior Rectal Branches
- Run transversely across the Ischioanal Fossa from the Pudendal Canal towards the Anal Canal
- Course arches convexly upwards through fat towards apex and then down towards the canal
- Incisions to drain Ischiorectal abscesses do not usually interfere with them
- Supplies the External Anal Sphincter, mucous membrane of the lower Anal Canal and peri-anal skin
- Divides in the Pudendal Canal into its terminal branches – Dorsal Nerve of the Penis and the Perineal Nerve
- Both nerves enter Deep Perineal Pouch
- Runs forwards above (Dorsal Nerve of the Penis) and below (Perineal Nerve) the Internal Pudendal Artery
- Dorsal Nerve of the Penis:
- Direct continuation of the Pudendal Nerve
- Pierces anterior angle of Perineal Membrane
- Accompanies Dorsal Artery on its lateral side
- Supplies: Skin of Penis, Glans, Corpus Cavernosum
- No branches in the Deep Perineal Pouch
- Perineal Nerve:
- Larger terminal branch of the Pudendal Nerve
- Supplies: Superficial and Deep Perineal muscles, Sphincter urethrae, Bulbospongiosus (same branch supplies sensory fibres to mucous membrane of Urethra)
- Gives off Posterior Scrotal Branches – runs forwards superficial to the Perineal Membrane to supply Scrotal Skin
