Dermatomes/Myotomes

Question 1

C1

Answer 1

Dermatome: vertex of skull
Myotome: cervical rotation

Question 2

C2

Answer 2

Dermatome: temple, forehead, occiput (POSTERIOR HEAD)
Myotome: n/a

Question 3

C3

Answer 3

Dermatome: Entire neck, posterior cheek, temporal area (POSTERIOR-LATERAL NECK)
Myotome: shoulder elevation

Question 4

C4

Answer 4

Dermatome: Shoulder area, clavicular area, upper scapular area (AC JOINT)
Myotome: shoulder elevation

Question 5

C5

Answer 5

Dermatome: Deltoid, anterior aspect of entire arm to thumb (LATERAL ARM)
Myotome: elbow flexion & shoulder abduction

Question 6

C6

Answer 6

Dermatome: anterior arm, radial side of hand to thumb and index finger (LATERAL ARM AND THUMB)
Myotome: wrist extension and elbow flexion

Question 7

C7

Answer 7

Dermatome: Lateral arm and forearm to index, long, and ring fingers (PALMAR DISTAL PHALANX MIDDLE FINGER)
Myotome: Elbow extension & wrist flexion

Question 8

C8

Answer 8

Dermatome: Medial arm and forearm to long, ring, and little fingers (LITTLE FINGER AND ULNAR BORDER OF HAND)
Myotome: thumb extension and finger flexion

Question 9

T1

Answer 9

Dermatome: Medial side of forearm to base of little finger (MEDIAL FOREARM)
Myotome: finger abduction

Question 10

T2

Answer 10

Dermatome: Medial side of upper arm to medial elbow, pectoral and midscapular regions
Myotome: n/a

Question 11

L1

Answer 11

Dermatome: Back, over trochanter and groin
Myotome: n/a

Question 12

L2

Answer 12

Dermatome: Back, front of thigh to knee (ANTERIOR THIGH)
Myotome: hip flexion

Question 13

L3

Answer 13

Dermatome: Back upper buttock, anterior thigh and knee, medial lower leg (MIDDLE THIRD OF ANTERIOR THIGH)
Myotome: knee extension

Question 14

L4

Answer 14

Dermatome: Medial buttock, lateral thigh, medial leg, dorsum of foot, big toe (PATELLA AND MEDIAL MALLEOLUS)
Myotome: Ankle DF

Question 15

L5

Answer 15

Dermatome: Buttock, posterior and lateral thigh, lateral aspect of leg, dorsum of foot, medial half of sole, first, second, and third toes (FIBULAR HEAD AND DORSUM OF FOOT)
Myotome: great toe extension (also glute med)

Question 16

S1

Answer 16

Dermatome: Lateral and plantar aspect of foot (LATERAL AND PLANTAR ASPECT OF FOOT)
Myotome: ankle PF and knee flexion

Question 17

S2

Answer 17

Dermatome: Buttock, thigh, and posterior leg (MEDIAL POSTERIOR THIGH)
Myotome: Same as S1 except peroneals (Hamstrings, gluteals, PF)

Question 18

S3

Answer 18

Dermatome: Groin, posteromedial thigh to knee
Myotome: n/a

Question 19

S4

Answer 19

Dermatome: Perineum, genitals, lower sacrum
Muscles: bladder, rectum