Pelvic splanchnic nerves or nervi erigentes are

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

that arise from sacral

spinal nerve A spinal nerve is a mixed nerve, which carries Motor neuron, motor, Sensory neuron, sensory, and Autonomic nervous system, autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each s ...

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 autonomic nervous system is responsible for regulat ...

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 reproduc ...

Structure

The pelvic splanchnic nerves arise from the

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

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 verteb ...

. They travel to their side's corresponding

inferior hypogastric plexus Inferior may refer to: * Inferiority complex * An anatomical term of location * Inferior angle of the scapula, in the human skeleton * ''Inferior'' (book), by Angela Saini * '' The Inferior'', a 2007 novel by Peadar Ó Guilín * Inferior good: ...

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

preganglionic In the autonomic nervous system, nerve fibers from the central nervous system to the autonomic ganglion, ganglion are known as preganglionic nerve fibers. All preganglionic fibers, whether they are in the sympathetic nervous system, sympathetic d ...

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 autonomic nervous system is responsible for regulat ...

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, which arise from the

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

and provide sympathetic efferent fibers.

Function

The pelvic splanchnic nerves contribute to the innervation of the

pelvic The pelvis (: pelves or pelvises) is the lower part of an anatomical 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). ...

and

genital A sex organ, also known as a reproductive organ, is a part of an organism that is involved in sexual reproduction. Sex organs constitute the primary sex characteristics of an organism. Sex organs are responsible for producing and transporting ...

organs. The nerves regulate the emptying of the

urinary bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the Kidney (vertebrates), kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the ...

, 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 f ...

, influence motility in the

rectum The rectum (: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. Before expulsion through the anus or cloaca, the rectum stores the feces temporarily. The adult ...

as well as

sex Sex is the biological trait that determines whether a sexually reproducing organism produces male or female gametes. During sexual reproduction, a male and a female gamete fuse to form a zygote, which develops into an offspring that inheri ...

ual functions like

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

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

cervix The cervix (: cervices) or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the time ...

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 Large intestine#Structure, colon. Anatomical position It crosses the abdomen from the ascending colon at the right colic flexure (hepatic flexure) with a downward ...

, and the rest of the proximal

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...

is supplied its parasympathetic fibers by the

vagus nerve The vagus nerve, also known as the tenth cranial nerve (CN X), plays a crucial role in the autonomic nervous system, which is responsible for regulating involuntary functions within the human body. This nerve carries both sensory and motor fibe ...

Clinical significance

Damage to the sacral spinal nerve roots can cause

neurogenic bladder dysfunction Neurogenic bladder dysfunction, often called by the shortened term neurogenic bladder, was technically termed neurogenic lower urinary tract dysfunction by the International Continence Society. It refers to urinary bladder problems due to disease ...

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—including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom ...

Society and culture

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

Parasites Lost "Parasites Lost" is the second episode in the third season of the American animated television series ''Futurama'', and the 34th episode of the series overall. Although the title is a play on John Milton's epic poem ''Paradise Lost'', the episo ...

", 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 and later revived by Comedy Central, and then Hulu. The series follows Philip J. Fry, who is cryogenically preserved for 1 ...

''; when protagonist Philip J. Fry is infected with

parasitic worms Parasitic worms, also known as helminths, are a polyphyletic group of large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other par ...

, the rest of the crew use micro-droids to enter his body with the intention of

tickling Tickling is the act of Haptic perception, touching a part of a person's body in a way that causes involuntary twitching movements or laughter. The laughter effect is inherently predicated upon the element of surprise, therefore normally does no ...

the pelvic splanchnic

ganglion A ganglion (: ganglia) is a group of neuron cell bodies in the peripheral nervous system. In the somatic nervous system, this includes dorsal root ganglia and trigeminal ganglia among a few others. In the autonomic nervous system, there are ...

to trigger a convulsive

bowel movement Defecation (or defaecation) follows digestion and is the necessary biological process by which organisms eliminate a solid, semisolid, or liquid waste material known as feces (or faeces) from the digestive tract via the anus or cloaca. The act ...

that they believe will expel the

worms The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive catalogue and list of names of marine organisms. Content The content of the registry is edited and maintained by scien ...

References

External links