Definition
The pudendal nerve is a nerve that runs through the pelvic and genital area. It is also called the “pubic nerve”. It is responsible for the motoric innervation of muscles as well as for sensitive innervation, i.e. all tactile and pressure sensations, in the area from the anus to the genitals.
Anatomy
The pudendal nerve has its origin in an interweaving of several nerves, also known as the plexus in medical terminology. This nerve plexus in turn originates in the lowest part of the spine, the sacrum, and the last vertebra of the upper lumbar spine. At the end of the nerve plexus, four individual nerve cords emerge.
One of these nerves is the pudendal nerve. It then moves through the pelvis, passing through several openings and moving around protrusions. It is accompanied by an artery and a vein.
The nerve then moves into the Canalis Pudendalis, also known as the ‘Alcock’ canal. A strong layer of connective tissue is placed in this canal around the pudendal nerve and its accompanying vein and artery. This channel represents a narrowing.
Once the pudendal nerve has finally passed through the Alcock Canal, it divides again into four further branches, its end branches. These include the perineal nerve, the inferior rectal nerve, the penile dorsal nerve and the clitoral dorsal nerve. These different nerve cords run in different directions and supply areas of the intimate and genital region.
The perineal nerves run in the direction of the perineum and scrotum in men and the labia majora in women. It also runs to parts of the muscles of the urethra. The inferior rectal nerves, on the other hand, run in the direction of the anus. The dorsal nerve penis and the dorsal nerve clitoridis both run to the penis in men and to the clitoridis in women.
Course of the pudendal nerve
The pudendal nerve originates from the spinal cord at the level of the sacrum. The nerve cords that come from the sacral segments S1 to S3, sometimes also S4, ultimately join together to form the pudendal nerve. The Pudendal Nerve then moves into the pelvis, where it passes through a large opening, the Foramen infrapiriforme.
It then moves around a prominence, the spina ischiadica, and then through another opening, the foramen ischiadicum minus, into the front part of the pelvis. Once there, it passes through the so-called ‘Alcock’ canal, whereupon it splits into its end branches. The end branches in turn mostly end in regions of the anus, perineum or genitals.
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