Lumbar Plexus Quiz

The Lumbar Plexus

• The lumbar plexus is part of the larger lumbosacral plexus.
• It's a major nervous pathway supplying the lower limb.
• It's formed by the upper four lumbar nerves.
• It gives off six major branches.

Branches of the Lumbar Plexus

• Iliohypogastric: Supplies the abdominal wall muscles and skin; has a cutaneous branch over the buttock. (L1)
• Ilioinguinal: Supplies the abdominal wall muscles and skin; has a cutaneous branch over the upper medial region. (L1)
• Genitofemoral: Supplies the genitals; has a cutaneous branch over the anterior surface. (L1, L2)
• Lateral femoral cutaneous: Supplies the lateral thigh skin. (L2, L3)
• Femoral: Largest branch of the lumbar plexus; supplies the anterior thigh muscles. (L2, L3, L4)
• Obturator: Supplies muscles in the medial compartment of the thigh. (L2, L3, L4)

Important Nerves - Detailed Information

• Femoral Nerve:

  • Root value: L2, L3, L4
  • Largest branch of the lumbar plexus.
  • Enters the thigh behind the inguinal ligament.
  • Main nerve of the anterior compartment of the thigh.

• Obturator Nerve:

  • Root value: L2, L3, L4
  • Passes through the obturator foramen into the thigh.
  • Main nerve of the medial (adductor) compartment of the thigh.

• Lateral cutaneous nerve of the thigh:

  • Root value: L2, L3
  • Enters the thigh under the lateral end of the inguinal ligament.
  • Supplies the skin of the anterior and lateral surfaces of the thigh.