Myotomes

This article is still missing information.

Commonly Tested Movements

Commonly tested movements. UMN column are movements that are preferentially weak in UMN lesions

Movement	UMN	Root	Reflex	Nerve	Muscle
Upper Limb
Shoulder abduction	++	C5		Axillary	Deltoid
Elbow flexion		C5/6 C6	+ +	Musculocutaneous Radial	Biceps Brachioradialis
Elbow extension	+	C7	+	Radial	Triceps
Radial wrist extension	+	C6		Radial	Extensor carpi radialis longus
Finger extension	+	C7		Posterior interosseous nerve	Extensor digitorum communis
Finger flexion		C8	+	Anterior interosseous nerve Ulnar	Flexor pollicis longus and flexor digitorum profundus (index) Flexor digitorum profundus (ring and little)
Finger abduction	++	T1 T1		Ulnar Median	First dorsal interosseous Abductor pollicis brevis
Lower Limb
Hip flexion	++	L1/2			Iliopsoas
Hip adduction		L2/3	+	Obturator	Adductors
Hip extension		L5/S1		Sciatic	Gluteus Maximus
Knee flexion	+	S1		Sciatic	Hamstrings
Knee extension		L3/4	+	Femoral	Quadriceps
Ankle dorsiflexion	++	L4		Deep peroneal	Tibialis anterior
Ankle eversion		L5/S1		Superficial peroneal	Peronei
Ankle plantarflexion		S1/S2	+	Tibial	Gastrocnemius, soleus
Big toe extension		L5		Deep peroneal	Extensor hallucis longus

Complete Myotome Chart

Complete Myotome Chart

Muscle	Myotome
Upper Limb
Supraspinatus	C5, C6
Infraspinatus	C5, C6
Deltoid	C5, C6
Pect major	C5, C6, C7, C8
Lat dorsi	C6, C7, C8
Biceps	C5, C6
Triceps	C6, C7, C8
Wrist extensors (radial)	C6, C7
EDC	C7, C8, T1
EPL	C7, C8, T1
FCR	C6, C7
FCU	C7, C8, T1
FDP radial digits	C8, T1
FDP ulnar digits	C7, C8, T1
FDS	C8, T1
FPL	C7, C8, T1
Thenar	C8, T1
Interossei	C7, C8, T1
Lower Limb
Iliopsoas	L1, L2, L3
Quadriceps femoris	L2, L3, L4
Adductor longus and magnus	L2, L3, L4
Gluteus medius, minimis, tensor fascia lata	L4, L5, S1
Gluteus maximus	L5, S1, S2
Semitendinosus	L5, S1, S2
Biceps femoris	L5, S1, S2
Semimembranosus	L5, S1, S2
Gastrocnemius and soleus	S1, S2
Tibialis posterior	L4, L5
Flexor digitorum longus	L5, S1, S2
Abductor hallucis, abductor digiti minimi, interossei	S1, S2
Tibialis anterior	L4, L5
Extensor digitorum longus	L5, S1
Extensor hallucis longus	L5, S1
Extensor digitorum brevis	L5, S1
Peroneus longus	L5, S1
Peroneus brevis	L5, S1

Myotome Dance

• C1, 2 – I nod to you – Neck flexion/extension
• C3 – Don’t tickle me – Neck lateral flexion
• C4 – I’m not sure – Shoulder elevation
• C5 – Feel alive – Shoulder flexion, abduction, & lateral rotation
• C6, 7, 8 – Close the gate – Shoulder extension, adduction & medial rotation
• C5, 6 – Pick up sticks – Elbow flexion
• C7, 8 – Lay them straight – Elbow extension
• C5, 6 – Flick my wrists – Forearm supination
• C7, 8 – The time is late – Forearm pronation
• C6, 7 – Fly up to heaven – Wrist flexion & extension
• C7 – Paper – Finger extension
• C8 – Rock – Finger flexion (though some sources say C7, 8 does both finger extension and flexion)
• T1 – Scissors – Finger abduction & adduction

• (T1-12 – Supplies chest wall and abdominal muscles)
• (L1 – Contributes to hip flexion & adduction)

Kicking a ball:

• L2, 3 – Lift my knee – Hip flexion
• L3, 4 – Kick the door – Knee extension (& knee-jerk reaction)
• L4, 5 – Foot points to the sky – Ankle dorsiflexion

Bringing foot back to the floor:

• L4, 5 – Extend my thigh – Hip extension
• L5, S1, (S2) – Kick my bum (Run to poo) – Knee flexion
• S1, 2 – Stand on my shoes – Ankle plantarflexion (& ankle jerk)
• (Babinski plantar reflex/extensor response in UMN lesion is L5, S1, S2)

• L2, 3, 4 – Modestly close the door – Hip adduction & internal/medial rotation
• L4 - S2 – The opposite is true – Hip abduction & external/lateral rotation

• C3, 4, 5 - Keeps the diaphragm alive → Innervates the diaphragm
• S2, 3, 4 – Keeps poo off the floor → Innervates bowel, bladder, sex organs, anal sphincter, pelvic muscles. (& anal wink reflex)