The myotomes are the group of muscles innervated by a single spinal nerve root

Region	Movement	Level		Region	Movement	Level
Shoulder	Abduction	C5		Hip	Flexion	L1/2
	Aduction	C5-7			Adduction	L2/3
Elbow	Flexion	C5/6			Extension	L5/S1
	Extension	C7		Knee	Flexion	L5/S1
Wrist	Flexion	C7/8			Extension	L3/4
	Extension	C7		Ankle	Dorsiflexion	L4
Fingers	Flexion	C8			Inversion	L4
	Extension	C7			Eversion	L5/S1
	Abduction	T1			Plantarflexion	S1/2
	Thumb abduction	C8/T1		Toe	Big toe extension	L5

Dermatomes

Level	Area
C3/4	Clavicles
C6/7	Lateral forearm
C6	Thumb
C7	Middle finger
C8	Little finger
T1	Medial side of arm
T4	Nipples
T10	Umbilicus
L1	Inguinal ligament
L2/3	Anterior and inner leg
L5	Medial side of big toe
L5-S2	Posterior and outer leg
S1	Lateral margin of foot and little toe
S2-4	Perineum