Week 8: Nerves of Thigh and Leg

Question 1

Answer 1

Structure: Iliohypogastric n.
Lateral cut. branches.
Anterior cut. branches.

Innervates the:

• Transversus abdominis.
• Internal oblique.
• Posterolateral gluteal and skin above pubis

Question 2

Answer 2

Structure: Ilioinguinal N.

Origin: L1, ventral division

Innervates:

• Interal Oblique
• skin of superomedial thigh and genital area

Question 3

Answer 3

Structure: Genitofemoral N.

Origin: L1, L2 ventral divisions

Innervates: cutaneous skin over femoral triangle and genital area

Question 4

Answer 4

Structure: Lateral cutaneous nerve of the thigh

aka lateral femoral cutaneous n.

Origin: L2, L3 dorsal divisions

Innervates: Cutaneous skin over the lateral aspect of the thigh down to the knee.

Question 5

Answer 5

Structure: Femoral Nerve

Origin: L2, L3, L4

Supplies:

• Iliacus, psoas major, sartorius, pectineus, rectus femoris, vastus lateralis, medialisand intermedialis. It also gives articular branches to the hip and knee joints.
• skin over the anterior and lateral thigh and the medial leg and foot.

Question 6

Answer 6

Structure: Obturator N.

Origin: L2, L3, L4

Supplies:

Motor: adductors of the thigh: adductor magnus, adductor longus, adductor brevis, obturator externus, and gracilis.

Sensory: hip and knee joints and cruciate ligaments.

Cutaneous: skin of the medial side of the thigh.

Question 7

Answer 7

Structure: Pudendal N.

Origin: S2, S3, S4: ventral divisions.

Innervates:

Motor: perineal muscles.

Cutaneous: skin of the perineum.

Question 8

Answer 8

Structure: Saphenous N.

Origin: Femoral N.

Supplies: skin of anteromedial aspect of leg and knee

Question 9

Answer 9

Structure: Superior gluteal nerve

Origin: Sacral plexus (post. divisions of ant. rami of L4-S1 spinal nerves)

Supplies:

• gluteus medius
• gluteus minimus
• tensor fasciae latae

Question 10

Answer 10

Structure: Inferior gluteal nerve

Origin: Sacral plexus L5-S2

Supplies: gluteus maximus

Question 11

Answer 11

Structure: Sciatic N.

Origin: sacral plexus L4-S3

Supplies:

semitendinous

semimembranosus

biceps femoris

adductor magnus

skin of leg and foot

all muscles of leg and foot

Question 12

Answer 12

Structure: Posterior femoral cutaneous n.

Origin: Ventral spinal rami S1-S3

Supplies:

• skin of posterior thigh and knee
• scrotum
• labia majora

Question 13

Answer 13

Structure: Tibial nerve

Origin: sciatic nerve

Supplies:

• posterior muscles of leg and knee joint
• skin of plantar foot and toes

Question 14

Answer 14

Structure: common fibular nerve

Origin: sciatic nerve

Supplies:

• knee joint via its articular branch
• skin on lateral part of posterior aspect of leg via lateral sural cutaneous nerve

Question 15

Answer 15

Structure: Deep Fibular N.

Origin: common fibular nerve

Supplies:

• tibialis anterior
• fibularis tertius
• extensor digitorum longus
• extsor hallucis longus

Question 16

Answer 16

Structure: Superficial fibular nerve

Origin: common fibular nerve

Supplies:

• fibularis longus and brevis
• skin on distal 1/3 of anterior surface of leg and dorsum of foot

Question 17

Identify the nerve highlighted in orange and indicated by the red arrow

Answer 17

Structure: Sural Nerve

Origin: branches of both tibial and common fibular nerves

Supplies:

• skin on posterior and lateral aspects of leg
• lateral side of foot

Question 18

Identify the nerve highlighted in orange and indicated by the red arrow

Answer 18

Structure: Lateral Plantar nerve

Origin: smaller terminal branch of tibial nerve

Supplies:

• quad. plantae
• abductor digiti minimi
• digiti minimi brevis
• deep branch supplies dorsal interossei, lateral three lumbricals and adductor hallucis,
• skin on sole lateral to a line splitting 4th digit

Question 19

Answer 19

Structure: Medial plantar nerve

Origin: Larger terminal branch of tibial nerve

Supplies:

• abd. hallucis
• flex. digitorum brevis
• flex. hallucis brevis
• first lumbrical
• skin of medial side of sole of foot and sides of first three digits