Lumbosacral Plexus

Question 1

Which branches of the lumbar plexus emerge lateral to psoas muscles?

Answer 1

Femoral
Iliohypogastric
Ilioinguinal
Lateral cutaneous nerve of the thigh

Question 2

What are the roots of the obturator nerve?

Answer 2

L2, L3, L4

Question 3

What are the roots of the femoral nerve?

Answer 3

L2, L3, L4

Question 4

What are the roots of the iliohypogastric nerve?

Answer 4

L1

Question 5

What are the roots of the ilioinguinal nerve?

Answer 5

L1

Question 6

What are the roots of the lateral cutaneous nerve of the thigh?

Answer 6

L2, L3

Question 7

Which 2 nerves make the sciatic nerve?

Answer 7

Tibial nerve

Common fibular nerve

Question 8

What are the roots of the common fibular nerve?

Answer 8

L4, L5, S1, S2

Question 9

What are the roots of the tibial nerve?

Answer 9

L4, L5, S1, S2, S3

Question 10

Define a motor unit

Answer 10

A motor neuron and the skeletal muscle fibres it innervates

Question 11

Define axial line

Answer 11

The junction of 2 dermatomes supplied from discontinuous spinal levels

Question 12

Which branches of the lumbar plexus emerge medial to psoas muscles?

Answer 12

Obturator nerve

Lumbosacral trunk

Question 13

What are the roots of the genitofemoral nerve?

Answer 13

L1, L2

Question 14

What are the roots of the superior gluteal nerve?

Answer 14

L4, L5, S1

Question 15

What are the roots of the inferior gluteal nerve?

Answer 15

L5, S1, S2

Question 16

What are the roots of the posterior femoral cutaneous nerve?

Answer 16

S1, S2, S3

Question 17

What are the roots of the pudendal nerve?

Answer 17

S2, S3, S4

Question 18

What is the role of the iliohypogastric nerve?

Answer 18

Supplies sensation to the skin over the lateral gluteal region
Motor innervation to the abdominal muscles

Question 19

Which spinal nerve roots contribute to the lumbar plexus?

Answer 19

L1 - L4

Question 20

What is the role of the ilioinguinal nerve?

Answer 20

Innervates skin on upper middle thigh and genitalia

Innervate abdominal muscles

Question 21

What is the role of the lateral cutaneous nerve of the thigh?

Answer 21

Innervate the skin of anterior, lateral thigh down to the knee

Question 22

Which muscles does the femoral nerve innervate?

Answer 22

Iliacus, pectineus, sartorius and all of the quadriceps

Question 23

Which parts of the skin does the femoral nerve innervate?

Answer 23

Anterior thigh

Medial leg

Question 24

Which muscles are innervated by the superior gluteal nerve?

Answer 24

Gluteus minimus
Gluteus medius
Tensor fascia lata

Question 25

Which muscles does the tibial portion of the sciatic nerve innervate?

Answer 25

Hamstrings (except short head of bicep femoris)
Hamstring part of adductor magnus
All the muscles in the sole of the foot

Question 26

Which parts of the skin does the tibial nerve innervate?

Answer 26

Medial and posterior, lateral surface of foot

Sole

Question 27

Which muscles does the common fibular nerve innervate?

Answer 27

Short head of biceps femoris
All muscles of anterior and lateral compartments of the leg
Extensor digitorum brevis

Question 28

Which parts of the skin does the common fibular nerve innervate?

Answer 28

Anterior, lateral surface of leg

Dorsum of foot

Question 29

What skin does the posterior femoral cutaneous nerve innervate?

Answer 29

Posterior surface of the thigh and the posterior surface of the leg