Genitofemoral nerve (L1–L2)

Nerves · L1 L2

Forms within psoas major, pierces it and runs down its anterior surface beneath the peritoneum, dividing above the inguinal ligament into genital and femoral branches.

Traced from the start

Detail

Genital branch: Enters the deep inguinal ring with the cord; supplies cremaster and the anterior scrotal or labial skin
Femoral branch: Passes deep to the inguinal ligament in the femoral sheath lateral to the artery; supplies skin over the femoral triangle
Reflex: Efferent limb of the cremasteric reflex (L1–L2); the reflex is characteristically absent in testicular torsion

When it goes wrong

Genital branch damaged at inguinal hernia repair or varicocele surgery, or the whole nerve stretched by a psoas abscess

Absent ipsilateral cremasteric reflex, numbness of the anterior scrotum or labium majus and of the skin over the femoral triangle

Practise this structure

1 question in the bank tagged Reflexes.

A 45-year-old storeman has three weeks of neck pain radiating into the right arm. Pushing a heavy door open with that arm is weak, and so is bending the wrist f…

Foundations · middle twist