myotomes and dermatomes of nerve root levels

Question 1

C1

Answer 1

dermatome: top of head

myotome: neck flexion

Question 2

C2

Answer 2

dermatome: back of head

myotome: neck flexion

Question 3

C3

Answer 3

dermatome: lateral neck

myotome: lateral neck flexion

Question 4

C4

Answer 4

dermatome: top of shoulder

myotome: shoulder elevation

Question 5

C5

Answer 5

dermatome: lateral upper arm

myotome:
deltoid- shoulder abduction
biceps- elbow flexion

reflex: biceps (bicep tendon)

Question 6

C6

Answer 6

dermatome: lateral forearm, thumb and index finger

myotome:
elbow- flexion
wrist- extension

reflex: brachioradialis

Question 7

C7

Answer 7

dermatome: middle finger

myotome:
elbow- extension
wrist- flexion

reflex: tricep

Question 8

C8

Answer 8

dermatome: medial forearm, ring and little finger

myotome:
thumb extension
ulnar deviation
finger flexion & abduction

Question 9

T1

Answer 9

dermatome: medial upper arm

myotome: finger- abduction/ adduction