Lumbar Plexus

Question 1

What forms the lumbar plexus?

Answer 1

anterior primary rami of L1, L2, L3, and part of L4

Question 2

What are the branches of the lumbar plexus?

Answer 2

• iliohypogastric nerve (L1)
• ilioinguinal nerve (L1)
• genitofemoral nerve (L1, L2)
• lateral cutaneous nerve of thigh (L2, L3)
• femoral nerve (L2, L3, L4)
• obturator nerve (L2, L3, L4)

Question 3

What does the iliohypogastric nerve supply?

Answer 3

sensory to the skin covering the pubis and gluteal region

Question 4

What does the ilioinguinal nerve supply?

Answer 4

• accompanies the spermatic cord/round ligament of the uterus through the inguinal canal
• emerges through the superficial inguinal ring to supply sensory innervation to the skin of the scrotum/labia majora and the thigh

Question 5

What are the branches of the genitofemoral nerve and what do they supply?

Answer 5

• genital branch: supplies the cremaster muscle

- femoral branch: supplies the skin over the femoral triangle

Question 6

What does the lateral cutaneous nerve of the thigh supply?

Answer 6

supplies the skin of the anterior and lateral aspects of the thigh

Question 7

What does the femoral nerve supply?

Answer 7

supplies the muscles and skin of the thigh

Question 8

What does the obturator nerve supply?

Answer 8

supplies the muscles and skin of the medial surface of the thigh

Question 9

What forms the sacral plexus?

Answer 9

anterior primary rami of L4 through S4