NVCC BIO 141 Muscles

Epicranius Frontalis

over forehead

elevated eyebrow

wrinkles forehead

Epicranius Occipitalis

over occipital

elevates eyebrows

wrinkles forehead

Orbicularis oris

around the mouth

closes lips

kissing muscle

Zygomaticus major

connects the zygomatic arch to corner of mouth

smiling muscle

origin: zygomatic bone

insertion: corners of orbicularis oris

Buccinator

hallow of cheek

compresses cheek

Platysma

lower border of mandible

pouting muscle

Orbicularis oculi

around eye

Closes eyelids; used in blinking, winking, and squinting

nasalis

covers the nose

flares. nostrils

compresses nasal cartilage

Masseter

over lateral mandible

elevates mandible

Origin: zygomatic arch

Insertion: lateral mandible

Temporalis

elevates mandible

biting

raises jaw

sternocleidomastoid

flexes head toward chest

roation/abduction of head

no

origin: sternoclavicular region

insertion: mastoid process of temporal

erector spinae spinalis (medial)

- group of midline dorsum muscles

-maintains posture

-erects spine

erector spinae longissiumus

-group of midline dorsum muscles

-maintains posture

-erects spine

Erector spinae iliocostalis

-group of midline dorsum muscles

-maintains posture

-erects spine

rhomboid major

-diamond shape deep to trapezius in back

-stabilizes, retracts, and pulls scapula toward the vertebral column

-paddling muscle

rhomboid minor

-diamond shape deep to trapezius in back

-stabilizes, retracts, and pulls scapula toward the vertebral column

-paddling muscle

serratus posterior (superior)

-deep to the rhomboid m.

-elevates ribs 2-5 and assists inhalation

-assists rotation and extension of trunk

-assists exhalation

serratus posterior (inferior)

-deep to the latissmus dorsi

-elevates ribs 2-5 and assists inhalation

-assists rotation and extension of trunk

-assists exhalation

splenius capitus

-superficial muscle back of the neck, deep to the trapezius

-extends or hyperextends the head

-used for shaking the head

trapezius

-trapezoid shaped muscle in posterior neck and upper back

-elevates pectoral girdle

elevates, retracts, or lowers scapula and shoulder

origin:occipital bone and spines of c7-t12

insertion: clavicle, spine and acromion process of scapulae

pectoralis minor

-muscle deep to pectoralis major

-scapula fixator

-abducts scapula

serratus anterior

-saw-toothed lateral thoracic muscle

-scapula fixator

-used for pushing or punching

levator scapuli

-deep to the trapezius in back and lateral to the neck

-elevates/adducts the scapula

pectoralis major

-large, convergent chest muscle

-flexes arm medially

-adducts arm

-origin: clavicle, sternum, and costal cartilages of ribs 1-6

-insertion: between tubercles of humerus

latissimus dorsi

-large back muscle

-adducts humerus

deltoid

-triangular shaped shoulder muscle

-abducts humerus

teres major

-scapula to humerus

-extends arm

-adducts and rotates arm medialy

teres minor

-scapula to humerus

-rotates arm laterally

- abducts arm

external intercostal

-origin: upper rib

insertion: lower rib

-elevates rib

internal intercostal

-origin: lower rib

-insertion: upper rib

depresses rib

infraspinatus

-insertion: humerus

-laterally rotates arm

-adducts arm

subscapularis

-insertion: humerus

-medialy rotates arm

supraspinatus

-insertion: humerus

-abducts humerus

brachialis

-muscle beneath biceps brachii

-flexes arm at elbow (synergist)

brachioradialis

-lateral muscle between upper arm and forearm

-flexes arm at the elbow (synergist)

triceps brachii

-posterior upper arm muscle (three heads)

-extends arm at elbow

diaphragm

-normal at rest (dome shape)

-during contraction (flat)

-increases size of chest

rectus abdominis

-origin: pubic crest and symphysis

-insertion: xiphoid process and costal cartilages of 5-7th ribs

-strap like muscle from costal cartilages to ilium

-tenses abdominal wall

-compresses and flexes trunk

external oblique

-superficial/lateral oblique abdominal muscle

-tenses abdominal wall

-compresses trunk

internal oblique

-deep oblique abdominal muscle

-tenses abdominal wall

-compresses trunk

transversus abdominis

-deep abdominal muscle that runs perpendicular to rectus abdominis

-tenses abdominal wall

-compresses trunk

quadratus lumborum

-posterior to the abdominal wall

-flexes vertebral column laterally

-maintains upright posture

(common source of low back pain)

illiopsoas illiacus

-dorsal hip muscles

-fan shaped

-attaches bodies of vertebra T12 and lumbar vertebra to the femur

-flexes thigh

-flexes trunk on thigh

-maintains posture

illiopsoas psoas major

-dorsal hip muscles

-fan shaped

-attaches bodies of vertebra T12 and lumbar vertebra to the femur

-flexes thigh

-flexes trunk on thigh

-maintains posture

gluteus maximus

-origin: dorsal ilium, sarcrum, coccyx

-insertion: posterior femur

-buttocks, largest muscle in body

-extends hip at thigh

gluteus medius

-lateral hip muscles

-abducts femur

adductor magnus

-located in medial of the thigh

-adducts femur

-flexes femur

-medial rotation

adductor longus

-located in medial of the thigh

-adducts femur

-flexes femur

-medial rotation

gracilis

-medial thigh muscle

-adducts femur

Piriformis

-posterior aspect of hip deep to the gluteus

-rotates and extends thigh laterally

quadratus femoris

-deep muscle posterior of hip joint

-external rotation

-stabilizes the head of femur in acetabulum

pectineus

-anterior and proximal part of thigh over adductor brevis

-flexes hip

-adducts and medially rotates thigh

rectus femoris

-anterior thigh quadriceps

-extends leg at knee

vastus lateralis

-lateral anterior thigh quadriceps

-extends leg at knee

vastus medialis

-medial anterior thigh quadriceps

-extends leg at knee

vastus intermedius

-deep anterior thigh quardriceps

-extends leg at knee

sartorius

origin: illiac spine

insertion: medial tibia

-parallel strap-like muscle that crosses thigh

-flexes knee forward

-abducts and laterally rotates knee

-tailor's muscle

biceps femoris

-posterior thigh hamstring

-flexes leg at knee

-extends thigh at hip

semitendinosus

-posterior thigh hamstring

-flexes leg at knee

semimembranosus

-posterior thigh hamstring

-flexes leg at knee

tibialis anterior

-anterior to tibia

-dorsiflexion

gastrocnemius

-origin: condyles of femur

insertion: calcaneus

-posterior lower leg

-plantar flexion

soleus

-deep to gastrocnemius

-planar flexion

biceps brachii

-origin: coracoid process

inertion: radial tuberosity

-fusiform, parallel, andterior upper arm muscle

-flexes arm at elbow