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 veneris in females. The femoral branch is different from the femoral nerve, which also arises from the lumbar plexus.
Plan of lumbar plexus. (Genitofemoral nerve visible at upper left.)
The lumbar plexus and its branches. (Genitofemoral nerve visible at upper left.)
|To||lumboinguinal, genital branch|
Anterior scrotum in malesMons pubis in females
|Anatomical terms of neuroanatomy|
The genitofemoral nerve originates from the upper L1-2 segments of the lumbar plexus. It passes downwards, pierces the psoas major and emerges from its anterior surface. The nerve divides into two branches, the genital branch and the lumboinguinal nerve also known as the femoral branch, both of which then continue downwards and medially to the inguinal and femoral canal respectively.
The genital branch passes through the deep inguinal ring and enters the inguinal canal. In men, the genital branch supplies the cremaster and scrotal skin. In women, the genital branch accompanies the round ligament of uterus, terminating in and innervating the skin of the mons pubis and labia majora.
The femoral branch passes underneath the inguinal ligament, travelling through the lateral muscular compartment of the femoral canal 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.
The genitofemoral nerve typically pierces and passes through the psoas major 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 or within the muscle belly of psoas major (with fibers of the psoas major 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 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. :262
- Deep and superficial dissection of the lumbar plexus.
- Genitofemoral nerve
- Drake, Richard L.; Vogl, Wayne; Tibbitts, Adam W.M. Mitchell; illustrations by Richard; Richardson, Paul (2005). Gray's anatomy for students (Pbk. ed.). Philadelphia: Elsevier/Churchill Livingstone. pp. 340–343. ISBN 978-0-443-06612-2.
- Anloague, Phillip; Huijbregts, Peter (2009). "Anatomical Variations of the Lumbar Plexus: A Descriptive Anatomy Study with Proposed Clinical Implications". Journal of Manual and Manipulative Therapy. 17 (4): e107-e114. doi:10.1179/106698109791352201. PMC 2813498.
- Anatomy photo:36:07-0305 at the SUNY Downstate Medical Center - "Inguinal Region, Scrotum and Testes: Layers of the spermatic cord"
- Anatomy figure: 40:07-13 at Human Anatomy Online, SUNY Downstate Medical Center - "Muscles and nerves of the posterior abdominal wall."
- posteriorabdomen at The Anatomy Lesson by Wesley Norman (Georgetown University) (posteriorabdmus&nerves)