Nerves (motor and sensory)

Question 1

What is the motor compartment and sensory innervation of the Obturator n. on the lower extremity? What vertebral levels does the Obturator n. originate?

Answer 1

Obturator n. (L2-4)

• Motor: medial compartment of thigh
• Sensory: medial thigh

Question 2

What is the sensory innervation of the Iliohypogastric n. on the lower extremity? What plexus does the Iliohypogastric n. originate?

Answer 2

Iliohypogastric n. (from Lumbar Plexus)

- Sensory: lateral upper thigh (hip area)

Question 3

What is the sensory innervation of the Ilioinguinal n. on the lower extremity? What plexus does the Ilioinguinal n. originate?

Answer 3

Ilioinguinal n. (from Lumbar Plexus)

- Sensory: medial upper thigh (groin area)

Question 4

What is the sensory innervation of the Genitofemoral n. on the lower extremity?

Answer 4

Genitofemoral n.

- Sensory: anterior upper thigh

Question 5

What is the motor compartment innervation of the Femoral n. on the lower extremity? What vertebral levels does the Femoral n. originate? What are the two sensory innervations (branches) of the Femoral n.?

Answer 5

Femoral n. (L2-4)

• Motor: anterior compartment of thigh
• Sensory: anterior thigh (anterior cutaneous branches) and anteromedial leg (saphenous n.)

Question 6

What vertebral levels make up the Sacral Plexus?

Answer 6

Lumbosacral trunk (anterior rami L4-5) + anterior rami S1-4

Question 7

What are the six branches of the Lumbar Plexus?

Answer 7

• Iliohypogastric n.
• Ilioinguinal n.
• Genitofemoral n.
• Lateral cutaneous n. of thigh (sensory only)
• Obturator n.
• Femoral n.

Question 8

What are the four branches of the Sacral Plexus?

Answer 8

• Superior gluteal n.
• Inferior gluteal n.
• Posterior cutaneous n. of thigh (sensory only)
• Sciatic n.

Question 9

What are the six motor compartments and two sensory innervations of the Sciatic n. on the lower extremity? What vertebral levels does the Sciatic n. originate?

Answer 9

Sciatic n. (L4-5, S1-3)

• Motor: all muscles in posterior thigh, entire leg (posterior, anterior and medial) and entire foot (plantar and dorsal)
• Sensory: lateral leg and skin of entire foot