Appendicular Muscles Function, Bio 201

pectoralis minor

pectoral girdle; draws scapula forwards and down

serratus anterior

pectoral girdle; rotates scapula laterally and upward (punching and planks)

levator scapulae

pectoral girdle; elevates/adducts scapula

trapezius

pectoral girdle; rotates, raises, and retracts scapula

rhomboideus minor & major

pectoral girdle; stabilize scapula, retract (adduct) scapula (squaring the shoulders)

pectoralis major

prime mover of arm flexion, rotates arm medially and adducts arm

latissimus dorsi

prime mover of arm extension, adducts and medially rotates

deltoid

prime mover of arm abduction

teres major

synergist to latissimus dorsi (lats little helper)

supraspinatus

rotator cuff; initiates abduction of arm (humerus)

infraspinatus

rotator cuff; rotates arm laterally

teres minor

rotator cuff; rotates arm laterally

subscapularis

rotator cuff; rotates arm medially

brachialis

a major elbow (forearm) flexor

biceps brachii

flexes elbow and supinates forearm (rotates arm laterally)

triceps brachii

prime mover of elbow extension (forearm)

brachioradialis

synergist in flexing forearm

pronator quadratus

prime mover of forearm pronation

pronator teres

pronates forearm

supinator

supinates forearm

flexor carpi radialis

flexes wrist and abducts hand

flexor carpi ulnaris

flexes wrist and adducts hand

flexor digitorum superficialis

flexes hand and fingers

extensor carpi radialis longus

extends and abducts wrist

extensor carpi radialis brevis

extends and abducts wrist

extensor digitorum

prime mover of finger extension

extensor carpi ulnaris

extends and adducts wrist

palmaris longus

tenses skin of palm (not always present)

ischiocavernosus

retards venous drainage and maintains erection of penis and clitoris

bulbosponginosus

empties male urethra, erection of penis and clitoris

pubococcygeus

levator ani muscle; of the pelvic diaphragm; supports pelvic viscera, constricts anal and vaginal sphincters

puborectalis

levator ani muscle; of the pelvic diaphragm; supports pelvic viscera, constricts anal and vaginal sphincters

iliococcygeus

levator ani muscle; of the pelvic diaphragm; supports pelvic viscera, constricts anal and vaginal sphincters

coccygeus

of the pelvic diaphragm; supports pelvic viscera

iliopsoas iliacus

prime mover for flexing thigh (hip joint) or flexing trunk at thigh

iliopsoas psoas

prime mover for flexing thigh (hip joint) or flexing trunk at thigh, plus flexes vertebral column laterally

iliotibial band/tract

n/a

tensor fasciae latae

braces knee when walking

gluteus maximus

major thigh extensor

gluteus medius

abducts and medially rotates thigh

adductor longus

adducts and medially rotate and flex thigh

adductor magnus

adduct and medially rotate and flex thigh

piriformis

laterally rotate thigh

gracilis

adducts thigh; flexes and medially rotates leg

rectus femoris

extends knee and flexes thigh at hip

rectus lateralis

extends and stabilizes knee

rectus medialis

extends knee

rectus intermedius

extends knee

sartorius

flexes, abducts and laterally rotates thigh; flexes knee (sitting cross legged)

biceps femoris

extends thigh and flexes knee

semitendinosus

extends thigh and flexes knee

semimembranosus

extends thigh and flexes knee

extensor digitorum longus

prime mover of toe extension

extensor hallicus longus

extends the big toe

tibialis anterior

prime mover of dorsiflexion

gastrocnemius

plantar flexes foot

soleus

plantar flexion

flexor hallicus longus

flexes big toe

tibialis posterior

prime mover of foot inversion

fibularis (peroneus) longus

plantar flexes and everts foot

flexor digitorum longus

flexes toes; plantar flexes and inverts foot