Upper Extremity Muscles

Front 1

Trapezius

Back 1

O: Superior nuchal line Ext. occipital protuberance Ligamentum nuchae Spinous processes C7-T12

I:Lateral clavicle Acromion Spine of scapula

Hint 1

Elevates, depresses and retracts scapula; tilts glenoid upward in abduction of arm

Front 2

Levator scapulae

Back 2

O: Transverse processes C1-C4

I:Upper part of medial border of scapula

Hint 2

Elevates scapula; tilts glenoid downward

Front 3

Rhomboideus major & minor

Back 3

O: Minor: Spinous processes C7-T1
Major: Spinous processes T2-T5

I: Vertebral (medial) border of scapula

Hint 3

Retract and elevate scapula; tilts glenoid downward in adduction of arm against resistance

Front 4

Serratus anterior

Back 4

O: Ribs 1-8

I: Anterior surface of medial border of scapula

Hint 4

Protracts scapula, rotates glenoid upward and holds scapula against thorax

Front 5

Pectoralis minor

Back 5

O: Ribs 3-5

I:Coracoid process

Hint 5

Protracts and depresses scapula

Front 6

Subscapularis

Back 6

O: Subscapular fossa

I: Lesser tubercle

Hint 6

Medially rotates arm; stabilizes shoulder joint

Front 7

Supraspinatus

Back 7

O: Supraspinous fossa

I: Greater tubercle (highest facet)

Hint 7

Abducts arm (initiates abduction); stabilizes shoulder joint

Front 8

Infraspinatus

Back 8

O: Infraspinous fossa

I: Greater tubercle (middle facet)

Hint 8

Laterally rotates arm; stabilizes shoulder joint

Front 9

Teres minor

Back 9

O: Lateral border of scapula

I: Greater tubercle (lowest facet)

Hint 9

Laterally rotates arm; stabilizes shoulder joint

Front 10

Latissimus dorsi

Back 10

O: Spinous processes T7-T12 Thoracolumbar fascia
Lumbar spinous processes Iliac crest Lower ribs

I:Intertubercular groove

Hint 10

Adducts, extends, and medially rotates humerus

Front 11

Teres major

Back 11

O: Inferior angle of scapula

I: Intertubercular groove

Hint 11

Adducts, extends and medially rotates arm

Front 12

Pectoralis major

Back 12

O: Clavicle, sternum (manubrium and body), costal cartilages, ext. oblique aponeurosis

I:Intertubercular groove

Hint 12

Adducts and medially rotates humerus; upper portion flexes arm; lower portion extends arm from flexed position

Front 13

Deltoideus

Back 13

O: Spine of scapula Acromion process Clavicle

I:Deltoid tuberosity

Hint 13

Flexes, abducts and extends arm

Front 14

Triceps brachii

Back 14

O: Long head - infraglenoid tubercle of
scapula Lateral head - posterolateral
humeral shaft Medial head - posteromedial humeral shaft

I: Olecranon process

Hint 14

Extends arm and forearm

Front 15

Biceps brachii

Back 15

O: Short head - coracoid process Long head - supraglenoid
tubercle of scapula

I:Radial tuberosity

Hint 15

Primarily supinates and flexes forearm; may help flex arm

Front 16

Coracobrachialis

Back 16

O: Coracoid process

I: Humeral shaft

Hint 16

Flexes and adducts arm

Front 17

Brachialis

Back 17

O: Humeral shaft

I: Ulnar tuberosity

Hint 17

Flexes forearm

Front 18

Pronator teres

Back 18

O: Humeral (superficial) head -
Medial epicondyle
Ulnar (deep) head -
Ant. proximal ulna

I:Middle lateral surface of radius

Hint 18

Pronates forearm and hand; flexes forearm

Front 19

Flexor carpi radialis

Back 19

O:Medial epicondyle

I:Base of 2nd metacarpal

Hint 19

Flexes and abducts hand

Front 20

Palmaris longus

Back 20

O: Medial epicondyle

I: Flexor retinaculum and palmar aponeurosis

Hint 20

Flexes hand and tenses palmar aponeurosis

Front 21

Flexor carpi ulnaris

Back 21

O: Humeral head -
Medial epicondyle
Ulnar head -
Olecranon process (medial edge)

I:Pisiform, hook of hamate and 5th metacarpal

Hint 21

Flexes and adducts hand

Front 22

Flexor digitorum superficialis

Back 22

O: Humeroulnar head -
Medial epicondyle, Ant. proximal ulna
Radial head -
Anterior radius

I:Middle phalanges of four fingers

Hint 22

Flexes proximal interphalangeal and metacarpophalangeal joints of four fingers, flexes wrist

Front 23

Flexor digitorum profundus

Back 23

O: Anterior ulna and interosseous membrane

I: Distal phalanges of four fingers

Hint 23

Flexes distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joints of four fingers; flexes wrist

Front 24

Flexor pollicis longus

Back 24

O: Anterior radius and interosseous membrane

I: Distal phalanx of thumb

Hint 24

Flexes interphalangeal and metacarpophalangeal joint of thumb

Front 25

Brachioradialis

Back 25

O: Lateral supracondylar ridge of humerus

I: Lateral surface of distal radius

Hint 25

Flexes forearm

Front 26

Extensor carpi radialis longus

Back 26

O: Lateral supracondylar ridge of humerus

I:Base of 2nd metacarpal

Hint 26

Extends and abducts hand

Front 27

Extensor carpi radialis brevis

Back 27

O: Lateral epicondyle

I:Base of 3rd metacarpal

Hint 27

Extends and abducts hand

Front 28

Extensor digitorum

Back 28

O:Lateral epicondyle

I:Dorsal surface of the distal and middle phalanges of 4 fingers

Hint 28

Extends fingers at metacarpophalangeal and interphalangeal joints

Front 29

Extensor carpi ulnaris

Back 29

O: Lateral epicondyle and posterior ulna

I:Base of 5th metacarpal

Hint 29

Extends and adducts hand

Front 30

Supinator

Back 30

O: Lateral epicondyle, radial collateral and annular ligaments, posterior ulna

I:Lateral, anterior and posterior radius

Hint 30

Supinates forearm

Front 31

Abductor pollicis longus

Back 31

O: Posterior ulna, interosseous membrane and posterior radius

I:Base of 1st metacarpal

Hint 31

Abducts and extends thumb

Front 32

Extensor pollicis brevis

Back 32

O:Posterior radius and interosseous membrane

I: Base of proximal phalanx of thumb

Hint 32

Extends thumb at MCP and CM joints

Front 33

Extensor pollicis longus

Back 33

O: Posterior ulna and interosseous membrane

I:Base of distal phalanx of thumb

Hint 33

Extends thumb at IP, MCP and CM joints

Front 34

Abductor pollicis brevis

Back 34

O: Flexor retinaculum, scaphoid, trapezium

I:Proximal phalanx of thumb

Hint 34

Abducts thumb; assists in early stages of opposition by rotating prox. phalanx slightly medially

Front 35

Flexor pollicis brevis

Back 35

O: Superficial head: flexor retinaculum, trapezium
Deep head: trapezoid, capitate (deep head often absent)

I: Proximal phalanx of thumb

Hint 35

Flexes thumb at CMC and MCP joints; aids in opposition

Front 36

Opponens pollicis

Back 36

O: Flexor retinaculum, trapezium

I:Radial margin of 1st metacarpal

Hint 36

Abducts, medially rotates and flexes metacarpal of thumb

Front 37

Abductor digiti minimi

Back 37

O: Pisiform

I: Proximal phalanx of little finger

Hint 37

Abducts little finger

Front 38

Flexor digiti minimi brevis

Back 38

O: Flexor retinaculum, hamate

I:Proximal phalanx of little finger

Hint 38

Flexes little finger (at MCP)

Front 39

Opponens digiti minimi

Back 39

O: Flexor retinaculum, hamate

I: Ulnar margin of 5th metacarpal

Hint 39

Draws 5th metacarpal forward and rotates it laterally

Front 40

Lumbrical muscles (4)

Back 40

O: Flexor digitorum profundus tendons

I: Radial edges of extensor hoods of all 4 fingers

Hint 40

Flex at MCP joint; extend at IP joints

Front 41

Adductor pollicis

Back 41

O: Oblique head: capitate, bases of 2nd and 3rd metacarpals
Transverse head: head of 3rd metacarpal

I: Proximal phalanx of thumb

Hint 41

Adducts and flexes thumb

Front 42

Palmar interosseous muscles (3)

Back 42

O: Metacarpals 2, 4 and 5

I: Extensor hoods and proximal phalanges (ulnar side for digit 2; radial side for digits 4 and 5)

Hint 42

Adduct digits 2, 4 and 5; flex these digits at the MCP joint and extend at the IP joints

Front 43

Dorsal interosseous muscles (4)

Back 43

O: Margins of the metacarpals filling all 4 interosseous spaces

I: Extensor hoods and proximal phalanges (radial sides for digits 2 and 3; ulnar sides for digits 3 and 4

Hint 43

Abduct digits 2, 3 and 4; flex these digits at the MCP joint and extend at the IP joints