Arm & Forearm Muscle Cards

Biceps brachii origin

Short head: Coracoid process of scapula; long head: supraglenoid tubercle of scapula

Biceps brachii insertion

Tuberosity of radius

Biceps brachii action

Shoulder flexion; short head assists shoulder adduction; long head assists shoulder abduction in lateral rotation; elbow flexion

Biceps brachii nerve

Musculocutaneous (C5, C6)

Brachialis origin

Anterior surface of distal 1/2 of humerus

Brachialis insertion

Tuberosity & coronoid process of ulna

Brachialis action

Elbow flexion

Brachialis nerve

Musculocutaneous (C5, C6)

Coracobrachialis origin

Coracoid process of scapula

Coracobrachialis insertion

Shaft of humerus opposite deltoid tuberosity

Coracobrachialis action

Shoulder flexion & adduction

Coracobrachialis nerve

Musculocutaneous (C6, C7)

Triceps brachii origin

Long head: Infraglenoid tubercle of scapula; lateral head: posterior & lateral surface of proximal ¼ humerus; medial head: posterior & medial surface of distal 2/3 humerus below radial groove

Triceps brachii insertion

olecranon process of ulna

Triceps brachii action

Elbow extension; long head assists shoulder extension & adduction

Triceps brachii nerve

Radial (C7, C8)

Anconeous origin

Lateral epicondyle of humerus

Anconeous insertion

olecranon & upper 1/4 posterior ulna

Anconeous action

Elbow extension; stabilizes ulna during supination

Anconeous nerve

Radial (C7, C8)

Pronator teres origin

Humeral head: Immediately proximal to medial epicondyle, common flexor tendon; ulnar head: coronoid process of ulna

Pronator teres insertion

Middle of lateral surface of radius

Pronator teres action

Forearm pronation; assists in elbow flexion

Pronator teres nerve

Median (C6, C7)

Flexor carpi radialis origin

Common flexor tendon from medial epicondyle of humerus

Flexor carpi radialis insertion

Base of 2nd MC; slip to 3rd MC

Flexor carpi radialis action

Flexion & abduction of wrist; assists in pronation & elbow flexion

Flexor carpi radialis nerve

Median (C6, C7)

Palmaris longus origin

Common flexor tendon from medial epicondyle of humerus

Palmaris longus insertion

Flexor retinaculum & palmar aponeurosis

Palmaris longus action

Wrist flexion; assists in elbow flexion

Palmaris longus nerve

Median (C7-T1)

Flexor carpi ulnaris origin

Humeral head: Common flexor tendon from medial epicondyle of humerus; ulnar head; olecranon process & proximal 2/3 posterior border of ulna

Flexor carpi ulnaris insertion

Pisiform; by ligaments to hamate & 5th MC

Flexor carpi ulnaris action

Wrist flexion & adduction; assists in elbow flexion

Flexor carpi ulnaris nerve

Ulnar (C8)

Flexor digitorum superficialis origin

Humeral head: Common flexor tendon from medial epicondyle of humerus; ulnar head: Coronoid process of ulna; radial head: oblique line of radius

Flexor digitorum superficialis insertion

Middle phalanges of digits 2-5

Flexor digitorum superficialis action

Flexion of proximal IP joints of digits 2-5; assists in flexion of MCPs & wrist

Flexor digitorum superficialis nerve

Median (C7-T1)

Flexor digitorum profundus origin

Anterior & medial surfaces of proximal ¾ ulna

Flexor digitorum profundus insertion

Anterior surface & bases of distal phalanges

Flexor digitorum profundus action

Flexion of distal IP joints of digits 2-5; assists in flexion of PIPs, MCPs, & wrist

Flexor digitorum profundus nerve

1 & 2 - median; 3 & 4 - ulnar (C8, T1)

Flexor pollicis longus origin

Anterior surface of radius below tuberosity, coronoid process of ulna, medial epicondyle of humerus

Flexor pollicis longus insertion

Palmar surface of base of distal phalanx of thumb

Flexor pollicis longus action

Flexion of IP joints of thumb; assists in flexion of MCPs & CMCs & wrist flexion

Flexor pollicis longus nerve

Median (C8, T1)

Pronator quadratus origin

Distal ¼ anterior & medial surface of ulna

Pronator quadratus insertion

Distal ¼ anterior & lateral surface of radius

Pronator quadratus action

Forearm pronation

Pronator quadratus nerve

Median (C8, T1)

Brachioradialis origin

Lateral supracondylar ridge of humerus

Brachioradialis insertion

Base of styloid process of radius

Brachioradialis action

Elbow flexion, forearm pronation

Brachioradialis nerve

Radial (C5, C6)

Extensor carpi radialis longus origin

Lateral supracondylar ridge of humerus

Extensor carpi radialis longus insertion

Dorsal & radial surface of base of 2nd MC

Extensor carpi radialis longus nerve

Radial (C6, C7)

Extensor carpi radialis brevis origin

Common extensor tendon from lateral epicondyle of humerus

Extensor carpi radialis brevis insertion

Dorsal surface of base of 3rd MC

Extensor carpi radialis brevis action

Wrist extension; assists in radial deviation

Extensor carpi radialis brevis nerve

Radial (C6, C7)

Extensor digitorum origin

Common extensor tendon from lateral epicondyle of humerus

Extensor digitorum insertion

Extensor hood with slip to middle phalanx & 2 lateral bands to distal phalanges of digits 2-5; to extensor hood of thumb

Extensor digitorum action

Extension of IP & MCP joints of digits 2-5; assists in abduction of digits 2, 4 & 5, wrist extension, & ulnar deviation

Extensor digitorum nerve

Radial (C6-C8)

Extensor digiti minimi origin

Common extensor tendon from lateral epicondyle of humerus

Extensor digiti minimi insertion

Extensor expansion of 5th digit

Extensor digiti minimi action

Extension of MCP & IP joints of 5th digit; assists in pinky abduction

Extensor digiti minimi nerve

Radial (C7, C8)

Extensor carpi ulnaris origin

Common extensor tendon from lateral epicondyle of humerus

Extensor carpi ulnaris insertion

Base of ulnar side of 5th MC & TFCC

Extensor carpi ulnaris action

Extension & ulnar deviation of wrist

Extensor carpi ulnaris nerve

Radial (C7, C8)

Supinator origin

Lateral epicondyle of humerus & supinator crest of ulna

Supinator insertion

Lateral surface of upper 1/3 radius

Supinator action

Forearm supination

Supinator nerve

Radial (C6)

Abductor pollicis longus origin

Posterior ulna distal to supinator crest; posterior surface of middle 1/3 radius

Abductor pollicis longus insertion

Base of radial side of 1st MC

Abductor pollicis longus action

Abduction & extension of CMC of thumb, radial deviation; assists in wrist flexion

Abductor pollicis longus nerve

Radial (C7, C8)

Extensor pollicis longus origin

Middle 1/3 posterior surface of ulna distal to origin of abductor pollicis longus

Extensor pollicis longus insertion

Base of dorsal surface of distal phalanx of thumb

Extensor pollicis longus action

Extension of IP, MCP, & CMC joints of thumb; assists in radial deviation & wrist extension

Extensor pollicis longus nerve

Radial (C7, C8)

Extensor pollicis brevis origin

Posterior radius distal to origin of abductor pollicis longus

Extensor pollicis brevis insertion

Base of dorsal surface of proximal phalanx of thumb

Extensor pollicis brevis action

Extension of MCP, extension & abduction of CMC of thumb; assists in radial deviation

Extensor pollicis brevis nerve

Radial (C7, C8)

Extensor indices origin

Posterior surface of ulna distal to origin of extensor pollicis longus

Extensor indices insertion

Extensor expansion of 2nd digit

Extensor indices action

Extension of MCP & IP of 2nd digit; assists in adduction of 2nd digit

Extensor indices nerve

Radial (C7, C8)

Adductor pollicis origin

Oblique fibers: Capitate & base of MC 2&3; transverse fibers: palmar surface of 3rd MC

Adductor pollicis insertion

Oblique fibers: Extensor expansion; transverse fibers: ulnar side & base of proximal phalanx of thumb

Adductor pollicis action

Adduction of CMC & MCP of thumb; assists in flexion of MCP, thumb opposition, & IP extension

Adductor pollicis nerve

Ulnar (C8, T1)

Abductor pollicis brevis origin

Tubercle of trapezium & tubercle of scaphoid