Shoulder and Arm Muscles: Origins, Insertions, Actions, Innervations

Teres major - Origin

Inferior angle of scapula

Teres major - Insertion

Crest of lesser tubercle of humerus

Teres major - Action

Extends, adducts, medially rotates shoulder joint

Teres major - Innervation

Not required

Deltoid - Origin

Acromial end of clavicle; acromion and spine of scapula

Deltoid - Insertion

Deltoid tuberosity of humerus

Deltoid - Action

Anterior: flexes shoulder joint; Lateral: abducts shoulder joint; Posterior: extends shoulder joint

Deltoid - Innervation

Axillary n.

Subscapularis - Origin

Subscapular fossa

Subscapularis - Insertion

Lesser tubercle of humerus

Subscapularis - Action

Medially rotates shoulder joint

Subscapularis - Innervation

Not required

Supraspinatus - Origin

Supraspinous fossa

Supraspinatus - Insertion

Greater tubercle of humerus

Supraspinatus - Action

Abducts shoulder joint

Supraspinatus - Innervation

Not required

Infraspinatus - Origin

Infraspinous fossa

Infraspinatus - Insertion

Greater tubercle of humerus

Infraspinatus - Action

Laterally rotates shoulder joint

Infraspinatus - Innervation

Not required

Teres minor - Origin

Lateral border of scapula

Teres minor - Insertion

Greater tubercle of humerus

Teres minor - Action

Laterally rotates shoulder joint

Teres minor - Innervation

Axillary n.

Coracobrachialis - Origin

Coracoid process of scapula

Coracobrachialis - Insertion

Medial humerus

Coracobrachialis - Action

Flexes, adducts shoulder joint

Coracobrachialis - Innervation

Musculocutaneous n.

Biceps brachii short head - Origin

Coracoid process of scapula

Biceps brachii short head - Insertion

Radial tuberosity

Biceps brachii short head - Action

Flexes elbow joint, supinates forearm

Biceps brachii short head - Innervation

Musculocutaneous n.

Biceps brachii long head - Origin

Supraglenoid tubercle of scapula

Biceps brachii long head - Insertion

Radial tuberosity

Biceps brachii long head - Action

Flexes elbow joint, supinates forearm

Biceps brachii long head - Innervation

Musculocutaneous n.

Brachialis - Origin

Distal anterior humerus

Brachialis - Insertion

Ulnar tuberosity; coronoid process of ulna

Brachialis - Action

Flexes elbow joint

Brachialis - Innervation

Musculocutaneous n.

Triceps brachii long head - Origin

Infraglenoid tubercle of scapula

Triceps brachii long head - Insertion

Olecranon process of ulna

Triceps brachii long head - Action

Extends elbow joint

Triceps brachii long head - Innervation

Radial n.

Triceps brachii lateral head - Origin

Middle posterior humerus

Triceps brachii lateral head - Insertion

Olecranon process of ulna

Triceps brachii lateral head - Action

Extends elbow joint

Triceps brachii lateral head - Innervation

Radial n.

Triceps brachii medial head - Origin

Distal posterior humerus

Triceps brachii medial head - Insertion

Olecranon process of ulna

Triceps brachii medial head - Action

Extends elbow joint

Triceps brachii medial head - Innervation

Radial n.

Pronator teres - Origin

Medial epicondyle humerus; coronoid process ulna

Pronator teres - Insertion

Lateral surface of radius

Pronator teres - Action

Pronates forearm, flexes elbow joint

Pronator teres - Innervation

Median n.

Flexor carpi radialis - Origin

Medial epicondyle of humerus

Flexor carpi radialis - Insertion

Palmar surface metacarpal II and III

Flexor carpi radialis - Action

Flexes wrist, abducts hand

Flexor carpi radialis - Innervation

Median n.

Palmaris longus - Origin

Medial epicondyle of humerus

Palmaris longus - Insertion

Palmar aponeurosis

Palmaris longus - Action

Flexes wrist

Palmaris longus - Innervation

Median n.

Flexor carpi ulnaris - Origin

Medial epicondyle of humerus; olecranon of ulna

Flexor carpi ulnaris - Insertion

Pisiform, hamate, palmar surface of metacarpal V

Flexor carpi ulnaris - Action

Flexes wrist, adducts hand

Flexor carpi ulnaris - Innervation

Ulnar n.

Flexor digitorum superficialis - Origin

Medial epicondyle of humerus; coronoid process ulna; proximal anterior radius

Flexor digitorum superficialis - Insertion

Palmar surface of middle phalanges of digits 2-5

Flexor digitorum superficialis - Action

Flexes digits 2-5, flexes wrist

Flexor digitorum superficialis - Innervation

Median n.

Brachioradialis - Origin

Lateral epicondyle of humerus

Brachioradialis - Insertion

Styloid process radius

Brachioradialis - Action

Flexes elbow joint

Brachioradialis - Innervation

Radial n.

Extensor carpi radialis longus - Origin

Lateral epicondyle of humerus

Extensor carpi radialis longus - Insertion

Dorsal surface metacarpal II

Extensor carpi radialis longus - Action

Extends wrist, abducts hand

Extensor carpi radialis longus - Innervation

Radial n.

Extensor carpi radialis brevis - Origin

Lateral epicondyle of humerus

Extensor carpi radialis brevis - Insertion

Dorsal surface metacarpal III

Extensor carpi radialis brevis - Action

Extends wrist, abducts hand

Extensor carpi radialis brevis - Innervation

Radial n.

Extensor digitorum - Origin

Lateral epicondyle of humerus

Extensor digitorum - Insertion

Dorsal surface digits 2-5

Extensor digitorum - Action

Extends wrist, extends digits 2-5

Extensor digitorum - Innervation

Radial n.

Extensor digiti minimi - Origin

Lateral epicondyle of humerus

Extensor digiti minimi - Insertion

Dorsal surface digit 5

Extensor digiti minimi - Action

Extends 5th digit, extends wrist

Extensor digiti minimi - Innervation

Radial n.

Extensor carpi ulnaris - Origin

Lateral epicondyle of humerus

Extensor carpi ulnaris - Insertion

Dorsal surface metacarpal V

Extensor carpi ulnaris - Action

Extends wrist, adducts hand

Extensor carpi ulnaris - Innervation

Radial n.

Anconeus - Origin

Lateral epicondyle of humerus

Anconeus - Insertion

Olecranon of ulna

Anconeus - Action

Extends elbow joint

Anconeus - Innervation

Radial n.