muscle actions

orbicularis oris

compresses and purses lips

zygomaticus minor

retracts and elevates upper lip

zygomaticus major

retracts and elevates corner of mouth

buccinator

compresses cheeks

risorius

draws corner of mouth laterally

mentalis

protrude and evert lower lip

orbicularis oculi

closes eye

corrugators cupercilii

pulls skin interiorly and medially

wrinkles brow

procerus

wrinkles nose

nasalis

compresses bridge

depresses tip of nose

elevates corner of nostrils

frontal belly of occipitofrontalis

raises eyebrows

wrinkles forehead

occipital belly of occipitofrontalis

tenses and retracts scalp

platysma

tenses skin of neck

pulls lower lip inferiorly

masseter

closes jaw

assists in protraction retraction and side to side of mandible

temporalis

close jaw

assists in retraction and moving mandible side to side

sternocleidomastoid (unilateral)

laterally flexes head to same side

rotates head opposite side

sternocleidomastoid (bilateral)

flexes neck

protracts head

aids in inhalation

scalenes

flex and side bends neck

elevates ribs 1 and 2 (aids inhalation)

serratus posterior superior

elevates ribs

aids in inhalation

serratus posterior inferior

depresses ribs

aids in exhalation

splenius capitis (unilateral)

rotates and laterally flexes neck

splenius capitis bilateral

extends neck

what makes up the erector spinae

iliocostalis thoracis

longissimus thoracis

spinalis thoraics

errector spinae

extend all of the vertebral spina

elevates and depresses ribs

what are the deep muscles of vertebral column

semispinalis capitis

multifidus

rotatores

intertranscersarii

deep muscles of vertebral column

stabilizes and provides delicate adjustment of vertebrae

slightly extends and rotates vertebrae

quadrates lumbroum unilateral

laterally flexes vertebral column

quadratus lumborum bilateral

depresses ribs during forced exhalation

stabilizes diaphragm during inhalation

external intercostals

elevates ribs

internal intercostals

depresses ribs

transversus thoracis

minimal significance

depresses ribs

diaphragm

contraction expands thoracic cavity

compresses abdominopelvic cavity

rectus abdominis

flexes vertebral column

acts to resist vertebral motion

forced exhalation

pyramidalis

tenses linea alba

external abdominal oblique

depresses ribs

flexes and laterally rotates vertebral column to the opposite side

internal abdominal oblique

depress ribs

flexes

laterally rotates vertebral column to the same side

traverse abdominis

compresses abdomen

forced exhalation

trapezius

retracts elevates depress and laterally rotates scapula

extends and flexes neck laterally

levator scapulae

elevates and slightly medially rates scapula

extends and bends neck laterally

rhomboideus (both)

elevates retracts (addicts) and slightly rotates scapula

pectoralis minor

depresses and protects and internally rotates scapula

subclavius

stabiles and depresses clavicle

serratus anterior

stabilizes

abducts and laterally rotates scapula

pectoralis major

flexes adducts and medially rotates arm

coracobrachialis

flexes and adducts arm

deltoid

whole muscles abducts arm

in part may flex extend and rotate arm

latissium dorsi

extends adducts and medials routes arm

draws should backward and downward

supraspinatus

abducts 10-15

infraspinatus

laterally rotates arm

may assist in adduction

teres minor

adducts and laterally rotates arm

subscapularis

adducts and medially rotates arm

teres major

adducts extends medially rotates arm

biceps brachii

flexes and supinates forearm

flex arm

brachialis

flexes forearm

triceps brachii

extends forearm

long head extends and adducts arm

pronator teres

pronates forearm

flexor carpi radialis

flexes and abducts hand

palmaris longus

flexes wrist and tightens palmar aponeurosis

flexor carpi ulnaris

flexes and adducts hand

flexor digitorum superficialis

flexes digits 2-5 at MP and PIP

flexes wrist

iliacus and psoas major

flexes thigh

psoas minor

weakly flexes trunk

tensor fascia latae

flexes and medially rotates thigh

tenses fascia lata which laterally supports the knee

sartorius

flexes and laterally rotates thigh

flexes and medially rotates leg

glutes maximus

extends and laterally rotates thigh

gluteus medius and minimus

abducts and medially rotates thigh

pectineus adductor longus adductor brevis

adducts and flexes thigh

adductor Magnus (adductor part)

flexes and weakly laterally rotates thigh

adductor Magnus (hamstring part)

extends and weakly medially rotates thigh

gracilis

adducts and flexes thigh

flexes and medially rotates tibia

deep hip lateral rotators

provide stability and maintain integrity of hip joint

assists with lateral rotation of the thigh

rectus femoris

flexes thigh

extends leg

vastus lateralis intermedius medialis

extends leg

biceps femoris

extends thigh

flexes and laterally rotates leg

semi tendinosus membranosus

extends thigh

flexes and medially rotates leg

tibialis anterior

dorsiflexes and inverts foot

extensor digitorum longus

dorsiflexes foot

extends digits 2-5

extensor hallicus longus

dorsiflexes foot

extends hallux

peroneus tertius

dorsiflexes and weakly everts foot

peroneus brevis and longus

everts foot

weakly plantar flexes

gastrocnemius

plantar flexes foot

flexes knee

soleus

plantar flexes foot

plantaris

weak leg and plantar flexor

popliteus

weakly flexes leg

strongly medially rotates tibia

tibialis posterior

plantar flexes and inverts foot

flexor digitorum longus

plantar flexes foot

flexes digits 2-5

flexor hallicus longus

plantar flexes foot

flexes hallux