Upper Limb Muscles: Actions, Origins, and Insertions for Anatomy Students

What are the actions of the biceps brachii

Flexes elbow, supinates forearm, weakly flexes shoulder

What is the origin of the biceps brachii

Short head: coracoid process of scapula; Long head: supraglenoid tubercle of scapula

What is the insertion of the biceps brachii

Radial tuberosity and bicipital aponeurosis

What are the actions of the brachialis

Primary flexor of the elbow

What is the origin of the brachialis

Distal half of anterior humerus

What is the insertion of the brachialis

Coronoid process and tuberosity of ulna

What are the actions of the brachioradialis

Flexes elbow (especially in neutral grip, halfway between pronation and supination)

What is the origin of the brachioradialis

Lateral supracondylar ridge of humerus

What is the insertion of the brachioradialis

Styloid process of radius

What are the actions of the triceps brachii

Extends elbow; long head also extends and adducts shoulder

What is the origin of the triceps brachii

Long head: infraglenoid tubercle of scapula; Lateral head: posterior humerus above radial groove; Medial head: posterior humerus below radial groove

What is the insertion of the triceps brachii

Olecranon process of ulna

What are the actions of the anconeus

Assists triceps in elbow extension, stabilizes elbow joint

What is the origin of the anconeus

Lateral epicondyle of humerus

What is the insertion of the anconeus

Olecranon and proximal posterior ulna

What are the actions of the supinator

Supinates forearm

What is the origin of the supinator

Lateral epicondyle of humerus and supinator crest of ulna

What is the insertion of the supinator

Lateral, posterior, and anterior surfaces of proximal radius

What are the actions of the pronator teres

Pronates forearm, assists elbow flexion

What is the origin of the pronator teres

Medial epicondyle of humerus and coronoid process of ulna

What is the insertion of the pronator teres

Lateral surface of radius, midshaft

What are the actions of the pronator quadratus

Pronates forearm

What is the origin of the pronator quadratus

Distal anterior ulna

What is the insertion of the pronator quadratus

Distal anterior radius

What are the actions of the extensor carpi ulnaris

Extends and adducts wrist

What is the origin of the extensor carpi ulnaris

Lateral epicondyle of humerus

What is the insertion of the extensor carpi ulnaris

Base of 5th metacarpal

What are the actions of the extensor carpi radialis (longus and brevis)

Extends and abducts wrist

What is the origin of the extensor carpi radialis

Longus: lateral supracondylar ridge; Brevis: lateral epicondyle of humerus

What is the insertion of the extensor carpi radialis

Base of 2nd and 3rd metacarpals

What are the actions of the extensor digitorum

Extends wrist and fingers (2-5)

What is the origin of the extensor digitorum

Lateral epicondyle of humerus

What is the insertion of the extensor digitorum

Extensor expansions of digits 2-5

What are the actions of the extensor digiti minimi

Extends small finger (5th digit)

What is the origin of the extensor digiti minimi

Lateral epicondyle of humerus

What is the insertion of the extensor digiti minimi

Extensor expansion of 5th digit

What are the actions of the extensor indicis

Extends index finger

What is the origin of the extensor indicis

Posterior ulna and interosseous membrane

What is the insertion of the extensor indicis

Extensor expansion of index finger

What are the actions of the flexor carpi radialis

Flexes and abducts wrist

What is the origin of the flexor carpi radialis

Medial epicondyle of humerus

What is the insertion of the flexor carpi radialis

Base of 2nd and 3rd metacarpals

What are the actions of the flexor carpi ulnaris

Flexes and adducts wrist

What is the origin of the flexor carpi ulnaris

Medial epicondyle of humerus, olecranon and posterior ulna

What is the insertion of the flexor carpi ulnaris

Pisiform, hook of hamate, base of 5th metacarpal

What are the actions of the palmaris longus

Flexes wrist, tenses palmar aponeurosis

What is the origin of the palmaris longus

Medial epicondyle of humerus

What is the insertion of the palmaris longus

Palmar aponeurosis

What are the actions of the flexor digitorum superficialis

Flexes wrist and PIP joints of digits 2-5

What is the origin of the flexor digitorum superficialis

Medial epicondyle of humerus, coronoid process of ulna, anterior radius

What is the insertion of the flexor digitorum superficialis

Middle phalanges of digits 2-5

What are the actions of the flexor digitorum profundus

Flexes wrist and DIP joints of digits 2-5

What is the origin of the flexor digitorum profundus

Anterior ulna and interosseous membrane

What is the insertion of the flexor digitorum profundus

Distal phalanges of digits 2-5

What are the actions of the flexor pollicis longus

Flexes distal phalanx of thumb

What is the origin of the flexor pollicis longus

Anterior radius and interosseous membrane

What is the insertion of the flexor pollicis longus

Distal phalanx of thumb

What are the actions of the abductor pollicis longus

Abducts and extends thumb at CMC joint

What is the origin of the abductor pollicis longus

Posterior radius, ulna, interosseous membrane

What is the insertion of the abductor pollicis longus

Base of 1st metacarpal

What are the actions of the extensor pollicis longus

Extends thumb at IP joint

What is the origin of the extensor pollicis longus

Posterior ulna and interosseous membrane

What is the insertion of the extensor pollicis longus

Distal phalanx of thumb

What are the actions of the extensor pollicis brevis

Extends thumb at MCP joint

What is the origin of the extensor pollicis brevis

Posterior radius and interosseous membrane

What is the insertion of the extensor pollicis brevis

Proximal phalanx of thumb

What are the actions of the abductor pollicis brevis

Abducts thumb

What is the origin of the abductor pollicis brevis

Flexor retinaculum, scaphoid, trapezium

What is the insertion of the abductor pollicis brevis

Proximal phalanx of thumb

What are the actions of the flexor pollicis brevis

Flexes thumb

What is the origin of the flexor pollicis brevis

Flexor retinaculum, trapezium

What is the insertion of the flexor pollicis brevis

Proximal phalanx of thumb

What are the actions of the opponens pollicis

Opposes thumb (abduction + flexion)

What is the origin of the opponens pollicis

Flexor retinaculum, trapezium

What is the insertion of the opponens pollicis

1st metacarpal

What are the actions of the adductor pollicis

Adducts thumb

What is the origin of the adductor pollicis

Capitate, bases of 2nd and 3rd metacarpals

What is the insertion of the adductor pollicis

Proximal phalanx of thumb

What are the actions of the abductor digiti minimi

Abducts little finger

What is the origin of the abductor digiti minimi

Pisiform

What is the insertion of the abductor digiti minimi

Proximal phalanx of 5th digit

What are the actions of the flexor digiti minimi brevis

Flexes little finger

What is the origin of the flexor digiti minimi brevis

Hook of hamate and flexor retinaculum

What is the insertion of the flexor digiti minimi brevis

Proximal phalanx of 5th digit

What are the actions of the opponens digiti minimi

Opposes little finger

What is the origin of the opponens digiti minimi

Hook of hamate and flexor retinaculum

What is the insertion of the opponens digiti minimi

5th metacarpal

What are the actions of the lumbricals

Flex MCP joints, extend IP joints

What is the origin of the lumbricals

Tendons of flexor digitorum profundus

What is the insertion of the lumbricals

Extensor expansions of digits 2-5

What are the actions of the palmar interossei

Adduct digits (PAD)

What is the origin of the palmar interossei

Metacarpals 2, 4, 5

What is the insertion of the palmar interossei

Proximal phalanges and extensor expansions

What are the actions of the dorsal interossei

Abduct digits (DAB)

What is the origin of the dorsal interossei

Adjacent sides of metacarpals

What is the insertion of the dorsal interossei

Proximal phalanges and extensor expansions

What is elbow flexion

Movement decreasing angle at elbow; caused by biceps brachii, brachialis, brachioradialis

What is elbow extension

Movement increasing angle at elbow; caused by triceps brachii, anconeus

What is forearm supination

Rotation of radius so palm faces up; caused by biceps brachii, supinator

What is forearm pronation

Rotation of radius so palm faces down; caused by pronator teres, pronator quadratus