Dermatomes and Myotomes

Question 1

What is a dermatome?

Answer 1

A spinal nerve that innervates a particular sensory area.

Question 2

What is a myotome?

Answer 2

A group of muscles that a single spinal nerve root innervates.

Question 3

C5

Answer 3

D: radial antecubital fossa
M: Shoulder abductors.
Elbow flexors (biceps, brachialis, and brachioradialis)

Question 4

C6

Answer 4

D: Thumb
M: Wrist extensors (extensor carpi radialis longus and brevis)

Question 5

C7

Answer 5

D: Middle finger
M: Elbow extensors (triceps). Wrist flexors

Question 6

C8

Answer 6

D: Little finger
M: finger flexors (distal phalanx - flexor digitorum profundus)

Question 7

T1

Answer 7

D: Ulnar antecubital fossa
M: Hand intrinsics (interossei)

Question 8

L2

Answer 8

D: Mid-anterior thigh
M: hip flexors (iliopsoas)

Question 9

L3

Answer 9

D: Medial femoral condyle
M: Knee extensors (quadriceps)

Question 10

L4

Answer 10

D: Medial malleolus
M: Ankle dorsiflexors

Question 11

L5

Answer 11

D: Dorsal second/third toe web space
M: Long toe extensors (extensor hallucis longus)

Question 12

S1

Answer 12

D: Lateral heel
M: Ankle plantar flexors (gastrocnemius, soleus)