MUSCLES MOVING THE UPPER

EXTREMITIES

Muscles that move the Humerus

Pectoralis major

Action: Flexes, adducts and

rotates arm medially at shoulder

Origin: Clavicle, sternum,

costal cartilage of upper ribs

Insertion: Humerus-greater

tubercle

Latissimus dorsi

Action: Extends, adducts and

rotates humerus medially, retracts the shoulder (swimmers muscle)

Origin: Spine of sacral lumbar

and lower thoracic vertebra. Iliac crest, and bottom 4 ribs.

Insertion: Intertubercular groove of

the humerus.

Deltoid Action:

Flexes and medially rotates arm, abducts arm, extends and laterally rotates arm.

Origin: acromian process,

spine of scapula, clavicle

Insertion: Deltoid tuberocity of

the humerous

Supraspinatus

Action: Abducts arm

Origin : Supraspinous

fossa of scapula Insertion:

Greater tubercle of humerus

Infraspinatus

Action: Adducts and

laterally rotates arm Origin:

Infraspinous fossa of scapula

Insertion: Greater tubercle of

humerus

Teres minor Action:

Adducts and laterally rotates arm

Origin: upper lateral

border of scapula Insertion:

Greater tubercle of humerus

Teres major Action:

Medially rotates and adducts arm

Origin: Inferior angle and

lateral border of scapula

Insertion: Crest of lesser

tubercle of the humerus

Muscles that act on the forearm

Triceps brachii Action:

Extend forearm Origin:

Long head-infraglenoid tubercle of the scapula

Lateral Head-posterior surface above radial groove.

Middle Head-posterior humerous below radial groove.

Insertion: Olecranon process of the

Ulna

Pass, Fail, Pass, Fail Pronator Teres Flexor carpi radialis Palmaris longus Flexor carpi ulnaris

Pronator Teres

Flexor carpi radialis

Flexor carpi ulnaris

Palmaris longus

THE 3 B’S THAT BEND THE ELBOW:

Biceps brachii, Brachioradialis, Brachialis

Biceps brachii Action:

Flex and supinate the forearm

Origin: Short head- goes to

the corocoid process of scapula

Long head-supraglenoid tubercle of scapula.

Insertion: radiotuberocity and

fascia of forearm

Brachioradialis

Action: Flexes forearm

Origin: lateral

supercondylar ridge of humerus.

Insertion: Styloid process of

radius

Brachialis Action:

Flexes forearm Origin:

The distal anterior surface of the humerus.

Insertion: The coronoid

process of the ulna

Pronators and SupinatorPronators

Pronator Quadratus Action: Pronates the hand Origin: the distal 4th of the ulna Insertion: distal 4th of the radius

Pronator Teres  Action: Pronates forearm Origin: the medial epicondyle of the humerus and coronoid

process of the ulna Insertion: Lateral surface of the radius.

Pronators

Pronator teres

Pronator quadratus

Supinator Action:

Supinates forearm

Origin: the laterally

epicondyle of the humerous and crest of the ulna.

Insertion: Lateral surface of

the proximal 3rd of the radius

MUSCLES THAT MOVE WRIST, HAND AND DIGITS

Palmar Interosseous muscles

Action: Adduct digits 2,4

and 5 Origin:

palmar surface of metacarpals 2,4,5

Insertion: sides of proximal

phalange bases for fingers 2,4,5

Dorsal Interosseous Muscles

Action: Abduct digits 2-4

Origin: adjacent sides of

metacarpal bones. Insertion:

dorsal tendons on fingers 2-5

Thenar Group

• Flexor pollicis brevis• Opponens pollicis • Abductor pollicis brevis

Actions: Flexes thumb

Abducts thumb Opposition of thumb

Don’t need to know origins/insertions

Hypothenar Group

Flexor digiti minimi brevis

Abductor digiti minimi

Opponens digiti minimi

Actions: Flexes finger 5 Abducts pinky

Opposition of pinkyDon’t need to know origins/insertions