Upper Extremity Muscle Cards

Front 1

Trapezius

Back 1

ORIGIN: 1) Upper Fibers- base of skull, occipital protuberance and posterior ligaments of neck 2) Middle Fibers: spinous processes of seventh cervical and upper three thoracic 3) Lower Fibers: spinous processes of 4-12 thoracic

INSERTION: 1) Upper Fibers- posterior aspect of the lateral third of the clavicle 2) Middle Fibers: medial border of the acromion process and upper border of the scapular spine 3) Lower Fibers: triangular space at the base of the scapular spine

ACTION: 1) Upper Fibers- elevation of the scapula, upward rotation and extension and rotation of the head at the neck 2) Middle Fibers- elevation, upward rotation and adduction (retraction) of the scapula 3) Lower Fibers: depression, adduction (retraction), and upward rotation of the scapula

Front 2

Flexor Carpi Radialis

Back 2

ORIGIN: medial epicondyle of the humerus

INSERTION: base of the second and third metacarpals, anterior (palmar surface)

ACTION:

1) wrist flexion and abduction

2) weak elbow flexion

3) weak forearm pronation

Front 3

Palmaris Longus

Back 3

ORIGIN: medial epicondyle of the humerus

INSERTION: palmar aponeurosis of 2-5 metacarpals

ACTION:

1) wrist flexion

2) weak elbow flexion

Front 4

Flexor carpi ulnaris

Back 4

ORIGIN:

1) medial epicondyle of the humerus

2) posterior aspect of the proximal ulna

INSERTION: pisiform, hamate, and base of the fifth metacarpal (palmar surface)

ACTION:

1) wrist flexion

2) adduction of the wrist together with the extensor carpi ulnaris muscle

3) weak flexion of the elbow

Front 5

Extensor carpi ulnaris

Back 5

ORIGIN:

1) lateral epicondyle of the humerus

2) middle two fourths of the posterior border of the ulna

INSERTION: base of the fifth metacarpal (dorsal surface)

ACTION:

1) extension of the wrist

2) adduction of the wrist together with the flexor carpi ulnaris muscle

3) weak extension of the elbow

Front 6

Extensor carpi radialis brevis

Back 6

ORIGIN: lateral epicondyle of the humerus

INSERTION: base of the third metacarpal

ACTION:

1) wrist extension and abduction

2) weak flexion of the elbow

Front 7

Extensor carpi radialis longus

Back 7

ORIGIN: distal third of lateral supracondylar ridge of the humerus and lateral epicondyle of the humerus

INSERTION: base of the second metacarpal (dorsal surface)

ACTION:

1) wrist extension and abduction

2) weak flexion of elbow

3) weak pronation to neutral from a fully supinated position

Front 8

Flexor digitorum superficialis

Back 8

ORIGIN: 1) medial epicondyle of the humerus

2) ulnar head- medial coronoid process

3) radial head- upper two thirds of the anterior border of the radius just distal to the radial tuberosity

INSERTION: each tendon splits and attaches to the sides of the middle phalanx of the four fingers

ACTION: 1) flexion of the fingers at the metacarpophalangeal and proximal interphalangeal joints

2) wrist flexion

3) elbow flexion

Front 9

Flexor digitorum profundus

Back 9

ORIGIN: proximal three-fourths of the anterior and medial ulna

INSERTION: base of the distal phalanxes of the four fingers

ACTION:

1) flexion of the four fingers at the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints

2) wrist flexion

Front 10

Flexor pollicis longus

Back 10

ORIGIN: middle anterior surface of the radius and the anterior medial border of the ulna just distal to the coronoid process; occasionally a small head is present attaching on the medial epicondyle of the humerus

INSERTION: base of the phalanx of the thumb (palmar surface)

ACTION:

1) flexion of the thumb carpometacarpal, metacarpophalangeal, and interphalangeal joints

2) wrist flexion

3) abduction of the wrist

Front 11

Extensor digitorum

Back 11

ORIGIN: lateral epicondyle of the humerus

INSERTION: four tendons to bases of middle and distal phalanxes of the four fingers (dorsal surface)

ACTION:

1) extension of the 2-5 phalanges at the metacarpophalangeal joints

2) wrist extension

3) weak elbow extension

Front 12

Extensor Indicis

Back 12

ORIGIN: between middle and distal one-third of the posterior ulna

INSERTION: base of the middle and distal phalanxes of the second phalange (dorsal surface)

ACTION:

1) extension of the index finger at the metacarpophalangeal joint

2) weak wrist extension

3) weak supination of the forearm from a pronated position

Front 13

Extensor digiti minimi

Back 13

ORIGIN: lateral epicondyle of the humerus

INSERTION: base of the middle and distal phalanxes of the fifth phalange (dorsal surface)

ACTION:

1) extension of the little finger at the metacarpophalangeal joint

2) weak wrist extension

3) weak elbow extension

Front 14

Extensor pollicis longus

Back 14

ORIGIN: posterior lateral surface of the lower middle ulna

INSERTION: base of the distal phalanx of the thumb (dorsal surface)

ACTION: 1) extension of the thumb at the carpometacarpal, metacarpophalangeal, and interphalangeal joints

2) wrist extension

3) wrist abduction

4) weak forearm supination from a pronated position

Front 15

Extensor pollicis brevis

Back 15

ORIGIN: posterior surface of the lower middle radius

INSERTION: base of the proximal phalanx of the thumb (dorsal)

ACTION:

1) extension of the thumb at the carpometacarpal and metacarpophalangeal joints

2) wrist abduction

3) weak wrist extension

Front 16

Abductor pollicis longus

Back 16

ORIGIN: posterior aspect of the radius and midshaft of the ulna

INSERTION: base of the first metacarpal (dorsal lateral surface)

ACTION:

1) abduction of the thumb at the carpometacarpal joint

2) abduction of the wrist

3) thumb extension at the carpometacarpal joint

4) weak supination of the forearm from pronated position

5) weak wrist extension

Front 17

Opponens pollicis

Back 17

ORIGIN:

1) anterior surface of the transverse carpal ligament

2) trapezium

INSERTION: lateral border of the 1st metacarpal

ACTION: carpometacarpal opposition of the thumb

Front 18

Abductor pollicis brevis

Back 18

ORIGIN:

1) anterior surface of transverse carpal ligament

2) trapezium

3) scaphoid

INSERTION: base of 1st proximal phalanx

ACTION: carpometacarpal abduction of thumb

Front 19

Flexor pollicis brevis

Back 19

ORIGIN:

1) superficial head: trapezium and transverse carpal ligament

2) deep head: ulnar aspect of 1st metacarpal

INSERTION: base of proximal phalanx of 1st metacarpal

ACTION:

1) carpometacarpal flexion and abduction

2) metacarpophalangeal flexion of thumb

Front 20

Adductor pollicis

Back 20

ORIGIN:

1) transverse head: anterior shaft of 3rd metacarpal

2) oblique head: base of 2nd and 3rd metacarpals, capitate, trapezoid

INSERTION: ulnar aspect of base of proximal phalanx of 1st metacarpal

ACTION:

1) carpometacarpal adduction

2) metacarpophalangeal flexion of thumb