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Updated: Oct 5, 2026

In Vitro Characterization of the Electrophysiological Properties of Colonic Afferent Fibers in Rats
Published on: September 27, 2017
[The inferior rectal nerve. Anatomical bases of perineal pain]
Material:
4 corpses (1 fresh, 3 formoled) without preliminary injection; age: 84 to 90.
Method:
a front access enabled us to show the origin of the inferior rectal nerve from the pudendal plexus, its course across the Alcook canal and the ischiorectal fossa. Then a posterior transgluteal access showed the short intragluteal course across the "biligamentary tunnel" (between sacrospinal and sacrotuberal ligaments) of nerves and vessels related to the anus, in particular the inconstant Morestin's nerve.
Results And Conclusion:
the compression of nerves causing perineal pain can occur at different places. Depending on the localisation of the origin and the course of the inferior rectal nerve (which change) in relation to the place of that compression, and also the existence or not of Morestin's nerve, the changing topography of these pains can be explained.
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