Pelvic splanchnic nerves or nervi erigentes are

splanchnic nerves The splanchnic nerves are paired visceral nerves (nerves that contribute to the innervation of the viscera, innervation of the internal organs), carrying fibers of the autonomic nervous system (visceral efferent fibers) as well as sensory fibers fr ...

that arise from

sacral Sacral may refer to: *Sacred Sacred describes something that is dedicated or set apart for the service or worship of a deity; is considered worthy of spiritual respect or devotion; or inspires awe or reverence among believers. The property ...

spinal nerve A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into th ...

s S2, S3, S4 to provide

parasympathetic The parasympathetic nervous system (PSNS) is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of t ...

innervation to the organs of the

pelvic cavity The pelvic cavity is a body cavity that is bounded by the bones of the pelvis. Its oblique roof is the pelvic inlet (the superior opening of the pelvis). Its lower boundary is the pelvic floor. The pelvic cavity primarily contains the reproducti ...

Structure

The pelvic splanchnic nerves arise from the

anterior rami The ventral ramus (pl. ''rami'') (Latin for ''branch'') is the anterior division of a spinal nerve. The ventral rami supply the antero-lateral parts of the trunk (anatomy), trunk and the limbs. They are mainly larger than the dorsal ramus of spinal ...

of the sacral

s S2, S3, and S4, and enter the

sacral plexus In human anatomy, the sacral plexus is a nerve plexus which provides motor and sensory nerves for the posterior thigh, most of the lower leg and foot, and part of the pelvis. It is part of the lumbosacral plexus and emerges from the lumbar vertebr ...

. They travel to their side's corresponding

inferior hypogastric plexus The inferior hypogastric plexus (pelvic plexus in some texts) is a network () of nerves that supplies the organs of the pelvic cavity. The inferior hypogastric plexus gives rise to the prostatic plexus in males and the uterovaginal plexus in female ...

, located bilaterally on the walls of the rectum. They contain both

preganglionic In the autonomic nervous system, fibers from the CNS to the ganglion are known as preganglionic fibers. All preganglionic fibers, whether they are in the sympathetic division or in the parasympathetic division, are cholinergic (that is, these ...

parasympathetic fibers as well as visceral afferent fibers. Visceral afferent fibers go to spinal cord following pathway of pelvic splanchnic nerve fibers. The

parasympathetic nervous system The parasympathetic nervous system (PSNS) is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of ...

is referred to as the ''craniosacral outflow''; the pelvic splanchnic nerves are the ''sacral'' component. They are in the same region as the

sacral splanchnic nerves Sacral splanchnic nerves are splanchnic nerves that connect the inferior hypogastric plexus to the sympathetic trunk in the pelvis. Structure The sacral sympathetic nerves arise from the sacral part of the sympathetic trunk, emerging anteriorly fr ...

, which arise from the

sympathetic trunk The sympathetic trunks (sympathetic chain, gangliated cord) are a paired bundle of nerve fibers that run from the base of the skull to the coccyx. They are a major component of the sympathetic nervous system. Structure The sympathetic trunk lies j ...

and provide sympathetic efferent fibers.

Function

The pelvic splanchnic nerves contribute to the innervation of the

pelvic The pelvis (plural pelves or pelvises) is the lower part of the trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis, or pelvic skeleton). The ...

and

genital A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction. The reproductive organs together constitute the reproductive system. In animals, the testis in the male, and the ovary in the female, a ...

organs. The nerves regulate the emptying of the

urinary bladder The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters ...

, control opening and closing of the

internal urethral sphincter The internal urethral sphincter is a urethral sphincter muscle which constricts the internal urethral orifice. It is located at the junction of the urethra with the urinary bladder and is continuous with the detrusor muscle, but anatomically and ...

, influence motility in the

rectum The rectum is the final straight portion of the large intestine in humans and some other mammals, and the Gastrointestinal tract, gut in others. The adult human rectum is about long, and begins at the rectosigmoid junction (the end of the s ...

as well as

sex Sex is the trait that determines whether a sexually reproducing animal or plant produces male or female gametes. Male plants and animals produce smaller mobile gametes (spermatozoa, sperm, pollen), while females produce larger ones ( ova, of ...

ual functions like

erection An erection (clinically: penile erection or penile tumescence) is a physiological phenomenon in which the penis becomes firm, engorged, and enlarged. Penile erection is the result of a complex interaction of psychological, neural, vascular, ...

. In the distal 1/3 of the transverse colon, and through the sigmoid and rectum, and the

cervix The cervix or cervix uteri (Latin, 'neck of the uterus') is the lower part of the uterus (womb) in the human female reproductive system. The cervix is usually 2 to 3 cm long (~1 inch) and roughly cylindrical in shape, which changes during ...

in females, the pelvic splanchnic nerves supply parasympathetic function, including transmitting the sensation of pain. The proximal 2/3 of the

transverse colon In human anatomy, the transverse colon is the longest and most movable part of the colon. Anatomical position It crosses the abdomen from the ascending colon at the right colic flexure (hepatic flexure) with a downward convexity to the descend ...

, and the rest of the proximal

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organ (biology), organs of the digestive syste ...

is supplied its parasympathetic fibers by the

vagus nerve The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and right ...

Clinical significance

Damage to the sacral spinal nerve roots can cause

neurogenic bladder dysfunction Neurogenic bladder dysfunction, or neurogenic bladder, refers to urinary bladder problems due to disease or injury of the central nervous system or peripheral nerves involved in the control of urination. There are multiple types of neurogenic bladde ...

and

fecal incontinence Fecal incontinence (FI), or in some forms encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents, both liquid stool elements and mucus, or solid feces. When this loss includes flatus (gas), it is referred ...

Society and culture

The pelvic splanchnic nerves are featured as a key plot point in "

Parasites Lost "Parasites Lost" is the second episode in season three of ''Futurama''. Although the title is a play on John Milton's epic poem ''Paradise Lost'', the episode is a parody of the 1966 film ''Fantastic Voyage''. It originally aired on the Fox networ ...

", a 2001 episode of the American animated TV comedy ''

Futurama ''Futurama'' is an American animated science fiction sitcom created by Matt Groening for the Fox Broadcasting Company. The series follows the adventures of the professional slacker Philip J. Fry, who is cryogenically preserved for 1000 years a ...

''; when protagonist

Philip J. Fry Philip J. Fry, commonly known by his surname, is a fictional character and the protagonist of the animated series '' Futurama''. He is voiced by Billy West using a version of his own voice as he sounded when he was 25. He is a slacker delivery ...

is infected with parasitic worms, the rest of the crew use micro-droids to enter his body with the intention of tickling the pelvic splanchnic ganglion to trigger a convulsive bowel movement that they believe will expel the worms.

References

External links