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01 · EMG · Muscles

Muscle Study Lab

73 EMG-relevant muscles with their root, trunk/cord, peripheral nerve, and action — three ways to drill them.

Browse the full table or drill click-to-reveal, grouped by nerve, region, or root.

Group:

Mode:

Muscle	Nerve	Roots	Cord / Trunk	Action
Deltoid	Axillary	C5, C6	Posterior cord	Shoulder abduction, flexion, extension
Teres minor	Axillary	C5, C6	Posterior cord	Shoulder external rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Rhomboids	Dorsal scapular	C5	Root (C5)	Scapular retraction and downward rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Serratus anterior	Long thoracic	C5, C6, C7	Roots (C5, C6, C7)	Scapular protraction and upward rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Teres major	Lower subscapular	C5, C6	Posterior cord	Shoulder adduction, internal rotation, extension

Muscle	Nerve	Roots	Cord / Trunk	Action
Pronator teres	Median	C6, C7	Lateral/Medial cord	Forearm pronation, elbow flexion
Flexor carpi radialis	Median	C6, C7	Lateral/Medial cord	Wrist flexion and radial deviation
Palmaris longus	Median	C7, C8	Lateral/Medial cord	Wrist flexion, tenses palmar aponeurosis
Flexor digitorum superficialis	Median	C7, C8, T1	Lateral/Medial cord	Finger flexion at PIP joints
Flexor digitorum profundus (digits 2&3)	Anterior interosseous	C7, C8, T1	Lateral/Medial cord	Finger flexion at DIP joints (index, middle)
Flexor pollicis longus	Anterior interosseous	C8, T1	Lateral/Medial cord	Thumb flexion at IP joint
Pronator quadratus	Anterior interosseous	C7, C8, T1	Lateral/Medial cord	Forearm pronation
Abductor pollicis brevis	Median	C8, T1	Lateral/Medial cord	Thumb abduction
Opponens pollicis	Median	C8, T1	Lateral/Medial cord	Thumb opposition

Muscle	Nerve	Roots	Cord / Trunk	Action
Biceps brachii	Musculocutaneous	C5, C6	Lateral cord	Elbow flexion, forearm supination
Brachialis (Musculocutaneous)	Musculocutaneous/Radial	C5, C6, C7	Lateral/Posterior cord	Elbow flexion
Coracobrachialis	Musculocutaneous	C5, C6, C7	Lateral cord	Shoulder flexion, adduction

Muscle	Nerve	Roots	Cord / Trunk	Action
Pectoralis major	Pectoral	C5, C6, C7, C8, T1	Lateral/Medial cord	Shoulder adduction, internal rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Brachioradialis	Radial	C5, C6	Posterior cord	Elbow flexion, forearm rotation
Triceps brachii	Radial	C6, C7, C8	Posterior cord	Elbow extension
Brachialis (Radial)	Musculocutaneous/Radial	C5, C6, C7	Lateral/Posterior cord	Elbow flexion
Anconeus	Radial	C7, C8	Posterior cord	Elbow extension, stabilizes elbow joint
Extensor carpi radialis	Radial	C6, C7	Posterior cord	Wrist extension and radial deviation
Supinator	Posterior interosseous	C5, C6	Posterior cord	Forearm supination
Extensor digitorum	Posterior interosseous	C7, C8	Posterior cord	Finger extension at MCP joints
Extensor carpi ulnaris	Posterior interosseous	C7, C8	Posterior cord	Wrist extension and ulnar deviation
Extensor pollicis longus	Posterior interosseous	C7, C8	Posterior cord	Thumb extension and retropulsion
Extensor indicis	Posterior interosseous	C7, C8	Posterior cord	Index finger extension
Abductor pollicis longus	Posterior interosseous	C7, C8	Posterior cord	Thumb abduction and extension

Muscle	Nerve	Roots	Cord / Trunk	Action
Trapezius (upper)	Spinal accessory	C3, C4	N/A (cranial nerve)	Shoulder elevation, scapular retraction

Muscle	Nerve	Roots	Cord / Trunk	Action
Subscapularis	Subscapular	C5, C6	Posterior cord	Shoulder internal rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Supraspinatus	Suprascapular	C5, C6	Upper trunk	Shoulder abduction initiation
Infraspinatus	Suprascapular	C5, C6	Upper trunk	Shoulder external rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Latissimus dorsi	Thoracodorsal	C6, C7, C8	Posterior cord	Shoulder adduction, extension, internal rotation

Muscle	Nerve	Roots	Cord / Trunk	Action
Flexor carpi ulnaris	Ulnar	C8, T1	Medial cord	Wrist flexion and ulnar deviation
Flexor digitorum profundus (digits 4&5)	Ulnar	C7, C8, T1	Medial cord	Finger flexion at DIP joints (ring, little)
Adductor pollicis	Ulnar	C8, T1	Medial cord	Thumb adduction
First dorsal interosseous	Ulnar	C8, T1	Medial cord	Index finger abduction
Abductor digiti minimi	Ulnar	C8, T1	Medial cord	Little finger abduction