HOME

TheInfoList



OR:

The genitofemoral nerve refers to a
nerve A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the ...
that is found 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 ...
. Its branches, the genital branch and femoral branch supply sensation to the upper anterior thigh, as well as the skin of the anterior
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 ...
in males and
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 ...
in females. The femoral branch is different from the
femoral nerve The femoral nerve is a nerve in the thigh that supplies skin on the upper thigh and inner leg, and the muscles that extend the knee. Structure The femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest ...
, which also arises from the lumbar plexus.


Anatomy

The genitofemoral nerve originates from the upper L1-2 segments of the lumbar plexus. It passes downwards, pierces the
psoas major 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 ilio ...
and emerges from its anterior surface. The nerve divides into two branches, the genital branch and the
lumboinguinal nerve The lumboinguinal nerve, also known as the femoral or crural branch of genitofemoral, is a nerve in the abdomen. The lumboinguinal nerve is a branch of the genitofemoral nerve. The "femoral" part supplies skin to the femoral triangle area. Struc ...
also known as the femoral branch, both of which then continue downwards and medially to the inguinal and femoral canal respectively.


Genital Branch

The genital branch continues downward on the surface of the psoas major muscle and then enters the inguinal canal through the deep inguinal ring. In men, the genital branch supplies the cremaster and scrotal skin. In women, the genital branch accompanies the
round ligament of 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 inguin ...
, terminating in and innervating 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 ...
.


Femoral Branch

The femoral branch passes underneath the
inguinal ligament The inguinal ligament (), also known as Poupart's ligament or groin ligament, is a band running from the pubic tubercle to the anterior superior iliac spine. It forms the base of the inguinal canal through which an indirect inguinal hernia may ...
, travelling through the lateral muscular compartment of the femoral sheath where it innervates skin of the upper leg. Passing through the cribriform fascia of the saphenous opening of the fascia lata of the thigh, it then supplies the skin of the upper, anterior and medial side of thigh.


Variation

The genitofemoral nerve typically pierces and passes through the
psoas major 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 ilio ...
muscle before bifurcating into a genital branch and a femoral branch midway along its anterior surface. In approximately 25% of cases, the genitofemoral nerve splits into these branches ''before'' it enters the
psoas major 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 ilio ...
or ''within'' the muscle belly of
psoas major 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 ilio ...
(with fibers of the
psoas major 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 ilio ...
separating the genital and femoral branches). Usually this variation causes the split to be occur earlier in the genitofemoral nerve, at the upper rather than mid-portion of the anterior surface of the
psoas major 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 ilio ...
.


Embryology

The genitofemoral nerve is formed in the midsection of the psoas muscle by the union of branches from the anterior rami of L1 and L2 nerve roots


Function

The genitofemoral nerve is responsible for both the sensory (femoral branch) and motor portions (genital branch) of the cremasteric reflex, which describes contraction of the cremasteric muscle when the skin of the superior medial part of the thigh is touched.


Additional images

File:Gray824.png, Deep and superficial dissection of the lumbar plexus. File:Slide6w.JPG, Genitofemoral nerve


See also


References


External links

* - "Inguinal Region, Scrotum and Testes: Layers of the spermatic cord" * - "Muscles and nerves of the posterior abdominal wall." * () {{Authority control Nerves of the lower limb and lower torso