Nerve Root Dermatomes, Myotomes, Reflexes, and Paraesthesias

Question 1

C1 Dermatome

Answer 1

Vertex of skull

Question 2

C2 Dermatome

Answer 2

Temple, forehead, occiput

Question 3

C3 Dermatome

Answer 3

Entire neck, posterior cheek, temoral area, prolongation forward under mandible

Question 4

C4 Dermatome

Answer 4

Shoulder area, clavicular area, upper scapular area

Question 5

C5 Dermatome

Answer 5

Deltoid area, anterior aspect of entire arm to base of thumb

Question 6

C6 Dermatome

Answer 6

Anterior arm, radial side of hand to thumb and index finger

Question 7

C7 Dermatome

Answer 7

Lateral arm and forearm to index, long, and ring fingers

Question 8

C8 Dermatome

Answer 8

Medial arm and forearm to long, ring, and little fingers

Question 9

C1 Myotome

Answer 9

None

Question 10

C2 Myotome

Answer 10

Longus colli, sternocleidomastoid, rectus capitis

Question 11

C3 Myotome

Answer 11

Trapezius, splenius capitis

Question 12

C4 Myotome

Answer 12

Trapezius, levator scapulae

Question 13

C5 Myotome

Answer 13

Supraspinatus, infraspinatus, deltoid, biceps

Question 14

C6 Myotome

Answer 14

Biceps, supinator, wrist extensors

Question 15

C7 Myotome

Answer 15

Triceps, wrist flexors (rarely wrist extensors)

Question 16

C8 Myotome

Answer 16

Ulnar deviators, thumb extensors, thumb adductors (rarely, triceps)

Question 17

Biceps/Brachioradialis Reflex Root

Answer 17

C5/C6

Question 18

Triceps Reflex Root

Answer 18

C7

Question 19

C3 Paresthesias

Answer 19

Cheek, side of neck

Question 20

C4 Paresthesias

Answer 20

Horizontal band along clavicle and upper scapula

Question 21

C6 Paresthesias

Answer 21

Thumb and index finger

Question 22

C7 Paresthesias

Answer 22

Index, long, and ring fingers

Question 23

C8 Paresthesias

Answer 23

Little finger along or with two adjacent fingers; not ring or long fingers, alone or together (C7)

Question 24

T1 Dermatome

Answer 24

Medial side of forearm to base of little finger

Question 25

T2 Dermatome

Answer 25

Medial side of upper arm to medial elbow, pectoral and midscapular areas

Question 26

L1 Dermatome

Answer 26

Back, over trochanter and groin

Question 27

L2 Dermatome

Answer 27

Back, front of thigh to knee

Question 28

L3 Dermatome

Answer 28

Back, upper buttock, anterior thigh and knee, medial lower leg

Question 29

L4 Dermatome

Answer 29

Medial buttock, lateral thigh, medial leg, dorsum of foot, big toe

Question 30

L5 Dermatome

Answer 30

Buttock, posterior and lateral thigh, lateral aspect of leg, dorsum of foot, medial half of sole, 1st, 2nd, and 3rd toes

Question 31

S1 Dermatome

Answer 31

Lateral and plantar aspect of foot

Question 32

S2 Dermatome

Answer 32

Buttock, thigh, and leg posterior

Question 33

S3 Dermatome

Answer 33

Groin, medial thigh to knee

Question 34

S4 Dermatome

Answer 34

Perineum, genitals, lower sacrum

Question 35

L2 Myotome

Answer 35

Psoas, hip adductors

Question 36

L3 Myotome

Answer 36

Psoas, quadriceps, thigh atrophy

Question 37

L4 Myotome

Answer 37

Tibialis anterior, extensor hallucis

Question 38

L5 Myotome

Answer 38

Extensor hallucis, peroneals, gluteus medius, dorsiflexors, hamstrings and calf atrophy

Question 39

S1 Myotome

Answer 39

Calf and hamstrings, wasting of gluteals, peroneasl, plantar flexors

Question 40

S2 Myotome

Answer 40

Calf and hamstrings, wasting of gluteals, plantar flexors

Question 41

S4 Myotome

Answer 41

Bladder, rectum

Question 42

Knee Jerk Reflex Root

Answer 42

L3/L4

Question 43

Achilles Reflex Root

Answer 43

S1/S2

Question 44

L1 Paresthesias

Answer 44

Groin; after holding posture, which causes pain

Question 45

L2 Paresthesias

Answer 45

Occasionally anterior thigh

Question 46

L3 Paresthesias

Answer 46

Medial knee, anterior lower leg

Question 47

L4 Paresthesias

Answer 47

Medial aspect of calf and ankle

Question 48

L5 Paresthesias

Answer 48

Lateral aspect of leg, medial three toes

Question 49

S1 Paresthesias

Answer 49

Lateral two toes, lateral foot, lateral leg to knee, plantar aspect of foot

Question 50

S2 Paresthesias

Answer 50

Lateral leg, knee, and heel

Question 51

S4 Paresthesias

Answer 51

Saddle area, genirals, anus, impotence, massive posterior herniation