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 belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the to ...

that arises from the

genitofemoral nerve The genitofemoral nerve refers to a nerve that is found in the abdomen. Its branches, the genital branch and femoral branch supply sensation to the upper anterior thigh, as well as the skin of the anterior scrotum in males and mons pubis in fema ...

. The genital branch supplies the

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

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 symp ...

and

labia majora The labia majora (singular: ''labium majus'') are two prominent longitudinal cutaneous folds that extend downward and backward from the mons pubis to the perineum. Together with the labia minora they form the labia of the vulva. The labia maj ...

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 grc, ψόᾱ, psóā, muscles of the loins) 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 il ...

, and pierces the fascia transversalis, or passes through the

deep inguinal ring The inguinal canals are the two passages in the anterior abdominal wall of humans and animals which in males convey the spermatic cords and in females the round ligament of the uterus. The inguinal canals are larger and more prominent in males. ...

. 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 The scrotum or scrotal sac is an anatomical male reproductive structure located at the base of the penis that consists of a suspended dual-chambered sac of skin and smooth muscle. It is present in most terrestrial male mammals. The scrotum co ...

, where it supplies the cremaster,

dartos muscle The dartos fascia or simply dartos is a layer of connective tissue found in the penile shaft, foreskin, scrotum and labia. The penile portion is referred to as the superficial fascia of penis or the subcutaneous tissue of penis, while the scrotal ...

and gives a few filaments to the skin of the scrotum. In females, it accompanies the

round ligament of the uterus The round ligament of the uterus is a ligament that connects the uterus to the labia majora. Structure The round ligament of the uterus originates at the uterine horns, in the parametrium. The round ligament exits the pelvis via the deep inguina ...

, 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 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