The genital branch of the genitofemoral nerve, also known as the external spermatic nerve in males, is a nerve in the

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

that arises from the

genitofemoral nerve The genitofemoral nerve is a mixed branch of the lumbar plexus derived from anterior rami of lumbar nerves L1–L2. It splits into a genital branch and a femoral branch. It provides sensory innervation to the upper anterior thigh, as well as t ...

. The genital branch supplies the cremaster muscle and anterior scrotal skin in males, and the skin of the

mons pubis In human anatomy, and in mammals in general, the ''mons pubis'' or pubic mound (also known simply as the mons , and known specifically in females as the ''mons Venus'' or ''mons veneris'') is a rounded mass of fatty tissue found over the pubic s ...

and

labia majora In primates, and specifically in humans, the labia majora (: labium majus), also known as the outer lips or outer labia, are two prominent Anatomical terms of location, longitudinal skin folds that extend downward and backward from the mons pubis ...

in females.

Structure

The genital branch of the genitofemoral nerve arises from the ventral primary divisions of L1-L2 spinal nerve roots. It passes outward on the

psoas major muscle The psoas major ( or ; from ) is a long fusiform muscle located in the lateral lumbar region between the vertebral column and the brim of the lesser pelvis. It joins the iliacus muscle to form the iliopsoas. In other animals, this muscle is equ ...

, and pierces the fascia transversalis, or passes through the

deep inguinal ring The inguinal canal is a passage in the anterior abdominal wall on each side of the body (one on each side of the midline), which in males, convey the spermatic cords and in females, the round ligament of the uterus. The inguinal canals are large ...

. It then descends within the

spermatic cord The spermatic cord is the cord-like structure in males formed by the vas deferens (''ductus deferens'') and surrounding tissue that runs from the deep inguinal ring down to each testicle. Its serosal covering, the tunica vaginalis, is an exten ...

. In males, it passes through to the

scrotum In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin ...

, where it supplies the cremaster, dartos muscle and gives a few filaments to the skin of the scrotum. In females, it accompanies the round ligament of the uterus, where it terminates as the nerve supplying the skin of the

and

Function

The genital branch of the genitofemoral nerve is responsible for the motor portion of the

cremasteric reflex The cremasteric reflex is a superficial (i.e., close to the skin's surface) reflex observed in human males. This reflex is elicited by lightly stroking or poking the superior and medial (inner) part of the thigh—regardless of the direction of ...

, which describes contraction of the

cremasteric muscle The cremaster muscle is a paired structure made of thin layers of striated and smooth muscle that covers the testicles and the spermatic cords in human males. It consists of the lateral and medial parts. Cremaster is an involuntary muscle, respo ...

when the skin of the superior medial part of the thigh is touched.

References

External links

* - "Inguinal Region, Scrotum and Testes: Layers of the Spermatic Cord" {{Authority control Nerves of the lower limb and lower torso Scrotum

Structure

Function

See also

References

External links