Supra and infralevator autonomic‐somatic communications: Computer‐assisted anatomic dissection in male and female foetuses

Abstract

Objectiveto identify the location and the nature of communications between supra and infralevator pathways.Materials and Methods6 male and 6 female human fetal pelvic specimens, 15 to 32 wk of gestation, were studied using the 3D computer‐assisted anatomic dissection (CAAD) with neural, nitrergic and myelin sheath markers.ResultsSupra and infra levator neural pathways cross each other distally in spatial X shape area. They yield dual innervation in 5 directions: 1‐anal sphincter, 2‐levator ani muscle, 3‐urethral sphincter, 4‐corpus spongiosum and perineal muscles, and 5‐corpora cavernosa. The communications between the two pathways exist in 3 levels: proximal supralevator, intermediary intralevator and distal infralevator. Distal communications exist when autonomic nitrergic cavernous nerves interact with some somatic nitrergic branches of the dorsal penis/clitoris nerve and carried the nitrergic activity in its distal portion.ConclusionsThe pelvic structures responsible for sphincters continence and sexual function receive a dual innervation from the autonomic supralevator and the somatic infralevator pathways. Distal communication takes over the nitrergic activity to the distal part of cavernous bodies in both gender and represents an important structure which may impact erectile function, especially during reconstructive surgery.Grant Funding Source: non