Dermatomes and Myotomes

Question 1

C4

Answer 1

Acromioclavicular joint (shoulder)

Shoulder shrugs

Question 2

C5

Answer 2

Lateral antecubital fossa (at elbow)

Shoulder Abduction and external rotation, Elbow flexion (Bicep)

Question 3

C6

Answer 3

Thumb (make figure of six)

Wrist flexion

Question 4

C7

Answer 4

Middle finger (swear)

Wrist flexion and elbow extension

Question 5

C8

Answer 5

Little finger (make an 8 with two hands)

Thumb extension and finger flexion

Question 6

T1

Answer 6

Medial antecubital fossa

Finger abduction

Question 7

T2

Answer 7

Apex of axilla

Question 8

T3-T12 dermatomes

Answer 8

Bands down the torso (T4 nipple, T10 umbilicus)

Question 9

L1

Answer 9

Upper anterolateral thigh

Question 10

L2

Answer 10

Mid anterolateral thigh

Hip flexion

Question 11

L3

Answer 11

Medial thigh

Knee extension

Question 12

L4

Answer 12

Medial shin/malleolus

Ankle dorsiflex

Question 13

L5

Answer 13

Lateral shin and dorm of foot

Knee flexion, hip flexion
Great toe extension

Question 14

S1

Answer 14

Lateral heel

Ankle plantar flex

Question 15

S2

Answer 15

Popliteal fossa

Question 16

S4-5 dermatome

Answer 16

Perianal area

Bladder and rectal motor supply

Question 17

What is light touch sensation mediated by

Answer 17

Dorsal/Posterior columns (Also proprioception here)

Question 18

What is pin prick sensation mediated by

Answer 18

Spinothalamic tracts

Question 19

Cervical plexus

Answer 19

C1-C4, innervated the diaphragm, shoulders and neck (3,4,5 diaphragm alive)

Question 20

Brachial plexus

Answer 20

C6-T1 innervates upper limbs

Question 21

Lumbosacral

Answer 21

L2-S1

innervates the lower extremities