Action

Deltoid

All = ABduct the shoulder

Ant. = flex, medially rotate, & horizontally adduct the shoulder

Post. = extend, laterally rotate, & horizontally abduct the shoulder

Teres Major

extend, ADduct, & medially rotate the shoulder

Teres Minor

• ADduct and laterally rotate the shoulder

• stabilize head of humerus in glenoid cavity

Supraspinatus

• ABduct shoulder

• stabilize head of humerus in glenoid cavity

Infraspinatus

• ADduct shoulder

• laterally rotate the shoulder

• stabilize head of humerus in glenoid cavity

Subscapularis

• Medially rotate shoulder

• stabilize head of humerus in glenoid cavity

Serratus Anterior

W/ origin fixed = abduct, upwardly rotate, and depress scapula & hold the medial border of the scapula against the rib cage

W/ scapula fixed = may act to elevate the thorax during forced inhalation

Pectoralis Major

• All Fibers = ADDuct shoulder, medially rotate shoulder, & assist to elevate the thorax during forced inhalation (w/ arm fixed)

• Upper Fibers = flex and Horiz. ADDuct shoulder

• Lower Fibers = extend shoulder

Pectoralis Minor

• depress, ABduct, & downwardly rotate scapula

• W/ scapula fixed = assist to elevate the thorax during forced inhalation

Subclavius

• Depress the clavicle & draw it anteriorly

• elevate 1st rib during inhalation

• stabilize the sternoclavicular joint

Biceps Brachii

• flex elbow

• supinate forearm

• flex shoulder

Triceps Brachii

• All Heads = extend elbow

• Long Head = extend & ADDuct shoulder

Coracobrachialis

flex & ADDuct shoulder

Brachialis

flex elbow

Brachioradialis

Flex elbow

(assist to pronate & supinate forearm during resistance)

Anconeus

extend elbow

Supinator

supinate forearm

Extensor Carpi Radialis Longus (ECRL)

extend & ABduct wrist

(assist to flex elbow)

Extensor Carpi Radialis Brevis (ECRB)

extend & ABduct wrist

(assist to flex elbow)

Extensor Indicis (EI)

extend & ADDuct 2nd finger

(may assist to extend wrist)

Extensor Digitorum (ED)

extend fingers 2-5

(assist to extend wrist)

Extensor Digiti Minimi (EDM)

extend 5th finger

Extensor Carpi Ulnaris (ECU)

extend & ADDuct wrist

Pronator Teres (PT)

pronate foraearm

(assist to flex elbow)

Flexor Carpi Radialis (FCR)

flex & ABduct wrist

Palmaris Longus (PL)

tense palmar fascia & flex wrist

(may assist to flex elbow)

Flexor Digitorum Superficialis (FDS)

Flex wrist & fingers 2-5 @ MCP and PIP joints

Flexor Digitorum Profundus (FDP)

flex fingers 2-5 @ MCP and DIP joints

Flexor Carpi Ulnaris (FCU)

flex & ADDuct wrist

(assist to flex elbow)

Pronator Quadratus (PQ)

pronate forearm

Abductor Pollicis Longus (APL)

• ABduct & extend thumb

• ABduct wrist

Extensor Pollicis Brevis & Longus

extend & ABduct thumb

Flexor Pollicis Longus (FPB)

flex thumb

(assist to flex wrist)

Adductor Pollicis (AP)

ADDuct thumb

(assist to flex thumb)

Abductor Pollicis Brevis (APB)

ABduct thumb

(assist thumb opposition)

Flexor Pollicis Brevis (FPB)

Flex thumb

(assist thumb opposition)

Opponens Pollicis (OP)

opposition of thumb at CMC joint

Lumbricals

• extend fingers 2-5 at IP joints

• flex fingers 2-5 at MCP joints

Palmar Interossei

ABduct thumb, 2nd finger, & 4th and 5th fingers towards 3rd finger

(assist to flex at MCP & extend at IP joints the 1-2 and 4-5 fingers)

Dorsal Interossei

ABduct fingers 2-4 at MCP joints

(assist to flex at MCP & extend at IP joints fingers 2-4

Abductor Digiti Minimi (ADM)

ABduct 5th finger

(assist in opposition of 5th finger to thumb)

Flexor Digiti Minimi Brevis (FDMB)

flex 5th finger

(assist in opposition of 5th finger to thumb)

Opponens Digiti Minimi (ODM)

opposition of 5th finger to thumb at CMC joint

Which muscles flex the elbow?

Main Muscles:

• biceps brachii

• brachialis

• brachioradialis

Muscles that Assist:

• flexor carpi radialis

• flexor carpi ulnaris

• palmaris longus

• pronator teres

• extensor carpi radialis longus

• extensor carpi radialis brevis

Which muscles extend the elbow?

Triceps brachii & Anconeus

Which muscles do supination?

• Biceps brachii

• Supinator

• Brachioradialis (assists)

Which muscles do pronation?

• Pronator Teres

• Pronator Quadratus

• Brachioradialis (assists)

Which muscles extend the wrist?

Main Muscles:

• extensor carpi radialis longus

• extensor carpi radialis brevis

• extensor carpi ulnaris

Muscles that assist:

• extensor digitorum

• extensor indicis

Which muscles flex wrist

Main Muscles:

• flexor carpi radialis

• flexor carpi ulnaris

• palmaris longus

• flexor digitorum superficialis

Muscles that assist:

• flexor digitorum profundus

• flexor pollicis longus