Upper Limb Muscles- Innervations And Actions

Front 1

Abductor Digiti Minimi- innveration

Back 1

Deep branch of ulnar nerve (C8, T1)

Front 2

Abductor Digiti Minimi- action

Back 2

Abducts 5th digit

Front 3

Abductor Pollicis Brevis- innervation

Back 3

Median nerve (C8, T1)

Front 4

Abductor Pollicis Brevis- action

Back 4

Abducts thumb and helps oppose it

Front 5

Abductor Pollicis Longus- innervation

Back 5

Deep branch of radial nerve (C7, C8)

Front 6

Abductor Pollicis Longus- action

Back 6

Abducts thumb and extends it at CMC joint

Front 7

Adductor Pollicis- innervation

Back 7

Ulnar nerve (C8, T1)

Front 8

Adductor Pollicis- action

Back 8

Draws 1st metacarpal laterally to oppose thumb toward center of palm and rotates it medially

Front 9

Aconeus- innervation

Back 9

Radial nerve (C7, C8, T1)

Front 10

Aconeus- action

Back 10

Assists triceps in extending forearm;
Stabilizes elbow joint;
Abducts ulna during pronation

Front 11

Biceps brachii- innervation

Back 11

Musculocutaneous nerve (C5, C6)

Front 12

Biceps brachii- action

Back 12

Supinates forearm and, when it is supine, flexes forearm

Front 13

Brachialis- innervation

Back 13

Musculocutaneous nerve (C5, C6)

Front 14

Brachialis- action

Back 14

Major flexor of forearm- flexes forearm in all positions

Front 15

Brachioradialis- innervation

Back 15

Radial nerve (C5, C6, C7)

Front 16

Brachioradialis- action

Back 16

Flexes forearm

Front 17

Coracobrachialis- innervation

Back 17

Musculocutaneous nerve (C5, C6, C7)

Front 18

Coracobrachialis- action

Back 18

Helps to flex and adduct arm

Front 19

Deltoid- innervation

Back 19

Axillary nerve (C5, C6)

Front 20

Deltoid- action (anterior part)

Back 20

Flexes and medially rotates arm

Front 21

Deltoid- action (middle part)

Back 21

Abducts arm

Front 22

Deltoid- action (posterior part)

Back 22

Extends and laterally rotates arm

Front 23

Extensor Carpi Radialis Brevis- innervation

Back 23

Deep branch of Radial nerve (C7, C8)

Front 24

Extensor Carpi Radialis Brevis- action

Back 24

Extend and abduct hand at wrist joint

Front 25

Extensor Carpi Radialis Longus- innervation

Back 25

Radial nerve (C7, C8)

Front 26

Extensor Carpi Radialis Longus- action

Back 26

Extend and abduct hand at wrist joint

Front 27

Extensor Carpi Ulnaris- innervation

Back 27

Extends and adducts hand at wrist joint

Front 28

Extensor Carpi Ulnaris- action

Back 28

Deep branch of Radial nerve (C7, C8)

Front 29

Extensor Digiti Minimi- innervation

Back 29

Deep branch of Radial nerve (C7, C8)

Front 30

Extensor Digiti Minimi- action

Back 30

Extends 5th digit at MCP and IP joints

Front 31

Extensor Digitorum- innervation

Back 31

Deep branch of Radial nerve (C7, C8)

Front 32

Extensor Digitorum- action

Back 32

Extends medial four digits at MCP joints
Extends hand at wrist joint

Front 33

Extensor Indicis- innervation

Back 33

Deep branch of Radial nerve (C7, C8)

Front 34

Extensor Indicis- action

Back 34

Extends 2nd digit and helps to extend hand

Front 35

Extensor Pollicis Brevis- innervation

Back 35

Deep branch of Radial nerve (C7, C8)

Front 36

Extensor Pollicis Brevis- action

Back 36

Extends proximal phalanx of thumb at CMC joint

Front 37

Extensor Pollicis Longus- innervation

Back 37

Deep branch of Radial nerve (C7, C8)

Front 38

Extensor Pollicis Longus- action

Back 38

Extends distal phalanx of thumb at carpometacarpal and interphalangeal joints

Front 39

Flexor Carpi Radialis- innervation

Back 39

Median nerve (C6, C7)

Front 40

Flexor Carpi Radialis- action

Back 40

Flexes and abducts hand (at wrist)

Front 41

Flexor Carpi Ulnaris- innervation

Back 41

Ulnar nerve (C7, C8)

Front 42

Flexor Carpi Ulnaris- action

Back 42

Flexes and adducts hand (at wrist)

Front 43

Flexor Digitorum Profundus- innervation (medial part)

Back 43

Ulnar nerve (C8, T1)

Front 44

Flexor Digitorum Profundus- innervation (lateral part)

Back 44

Median nerve (C8, T1)

Front 45

Flexor Digitorum Profundus- action

Back 45

Flexes distal phalanges at distal IP joints of medial four digits
Assists with flexion of hand

Front 46

Flexor Digiti Minimi Brevis- innervation

Back 46

Deep branch of Ulnar nerve (C8, T1)

Front 47

Flexor Digiti Minimi Brevis- action

Back 47

Flexes proximal phalanx of little (5th) finger

Front 48

Flexor Digitorum Superficialis- innervation

Back 48

Median nerve (C7, C8, T1)

Front 49

Flexor Digitorum Superficialis- action

Back 49

Flexes middle phalanges at proximal IP joints of medial four digits; acting more strongly, it also flexes proximal phalanges at MCP joints and hand

Front 50

Flexor Pollicis Brevis- innervation

Back 50

Median nerve (C8, T1)

Front 51

Flexor Pollicis Brevis- action

Back 51

Flexes pollex

Front 52

Flexor Pollicis Longus- innervation

Back 52

Median nerve (C8, T1)

Front 53

Flexor Pollicis Longus- action

Back 53

Flexes pollex

Front 54

Infraspinatus- innervation

Back 54

Suprascapular nerve (C5, C6)

Front 55

Infraspinatus- action

Back 55

Laterally rotate arm;
Helps to hold humeral head in glenoid cavity of scapula

Front 56

Interossei (dorsal)- innervation

Back 56

Ulnar nerve (C8, T1)

Front 57

Interossei (dorsal)- action

Back 57

Dorsal 1 - 4: Abduct digits from axial line and act with lumbricals to flex MCP joints and extend IP joints

Front 58

Interossei (palmar)- innervation

Back 58

Ulnar nerve (C8, T1)

Front 59

Interossei (palmar)- action

Back 59

Palmar 1 - 3: Adduct digits toward axial line and assist lumbricals in flexing MCP joints and extending IP joints

Front 60

Latissimus Dorsi- innervation

Back 60

Thoracodorsal nerve (C6, C7, C8)

Front 61

Latissimus Dorsi- action

Back 61

Extends, adducts, and medially rotates humerus
Raises body toward arms during climbing

Front 62

Levator Scapulae- innervation

Back 62

Dorsal scapular nerve (C5)
Cervical nerves (C3, C4)

Front 63

Levator Scapulae- action

Back 63

Elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula

Front 64

Opponens Digiti Minimi- innervation

Back 64

Deep branch of Ulnar nerve (C8, T1)

Front 65

Opponens Digiti Minimi- action

Back 65

Draws 5th metacarpal anteriorly and rotates it, bringing little finger (5th digit) into opposition with thumb

Front 66

Opponens Pollicis- innervation

Back 66

Median nerve (C8, T1)

Front 67

Opponens Pollicis- action

Back 67

Draws 1st metacarpal laterally to oppose thumb toward center of palm and rotates it medially

Front 68

Palmaris Longus- innervation

Back 68

Median nerve (C7, C8)

Front 69

Palmaris Longus- action

Back 69

Flexes hand at the wrist

Front 70

Pectoralis Major- innervation

Back 70

Lateral and Medial Pectoral nerves (C5, C6, C7, C8, T1)

Front 71

Pectoralis Major- action

Back 71

Adducts and medially rotates humerus; draws scapula anteriorly and inferiorly; Acting alone: clavicular head flexes humerus and sternocostal head extends it

Front 72

Pectoralis Minor- innervation

Back 72

Medial Pectoral nerves (C8, T1)

Front 73

Pectoralis Minor- action

Back 73

Stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall

Front 74

Pronator Quadratus- innervation

Back 74

Median nerve (C8, T1)

Front 75

Pronator Quadratus- action

Back 75

Pronates forearm; deep fibers bind radius and ulna together

Front 76

Pronator Teres- innervation

Back 76

Median nerve (C6, C7)

Front 77

Pronator Teres- action

Back 77

Pronates and flexes forearm (at elbow)

Front 78

Rhomboids- innervation

Back 78

Dorsal Scapular nerve (C4, C5)

Front 79

Rhomboids- action

Back 79

Retract scapula and rotate it to depress glenoid cavity; fix scapula to thoracic wall

Front 80

Serratus Anterior- innervation

Back 80

Long thoracic nerve (C5, C6, C7)

Front 81

Serratus Anterior- action

Back 81

Draws scapula forward and upward; abducts scapula and rotates it; stabilizes vertebral border of scapula

Front 82

Subscapularis- innervation

Back 82

Upper and Lower Subscapular nerves (C5. C6, C7)

Front 83

Subscapularis- action

Back 83

Medially rotates arm and adducts it; helps to hold humeral head in glenoid cavity of scapula

Front 84

Supinator- innervation

Back 84

Deep branch of Radial nerve (C5, C6)

Front 85

Supinator- action

Back 85

Supinates forearm (i.e., rotates radius to turn palm anteriorly)

Front 86

Supraspinatus- innervation

Back 86

Suprascapular nerve (C4, C5, C6)

Front 87

Supraspinatus- action

Back 87

Initiates and assists deltoid in abduction of arm and acts with other rotator cuff muscles

Front 88

Teres Major- innervation

Back 88

Lower Subscapular nerve (C6, C7)

Front 89

Teres Major- action

Back 89

Adducts and medially rotates arm

Front 90

Teres Minor- innervation

Back 90

Axillary nerve (C5, C6)

Front 91

Teres Minor- action

Back 91

Laterally rotate arm; helps to hold humeral head in glenoid cavity of scapula

Front 92

Trapezius- innervation

Back 92

Spinal root of accessory nerve (CN XI) (motor)

Cervical nerves (C3 and C4) (pain and proprioception)

(XI, C3, C4)

Front 93

Trapezius- action

Back 93

Elevates, retracts and rotates scapula; superior fibers elevate, middle fibers retract, and inferior fibers depress scapula; superior and inferior fibers act together in superior rotation of scapula

Front 94

Triceps Brachii- innervation

Back 94

Radial nerve (C6, C7, C8)

Front 95

Triceps Brachii- action

Back 95

Chief extensor of forearm; long head steadies head of abducted humerus