ch 4 muscular system

neuromuscular junction

motor neuron innervates muscle fiber

innervates

start/activate

neur/o-

nerve

muscul/o

muscle

my/o

muscle

antagonist

1 contracts & 1 relaxes

ex: antagonist muscle relaxes when agonist contracts

agonist

does the work

ex: bicep contracts and does the work, tricep relaxes=antagonist

contraction

muscle shortens & thickens

relaxation

muscle is longer

abduct

motion of muscles away from midline

adduct

motion of muscles towards midline

-ion

action

add-

toward

duct-

lead

flexion

decrease angle @ joint b/t two bones

extension

increase angle @ joint

hyperextension

overextend angle

supine

rotate palm, ventral side

pronate

rotate palm, ventral side down

dorsiflexion

bend foot upward at ankle toward tibia, dec joint angle

dorsi=back

plantar flexion

increased angle b/t shin & top of foot by pointing toes down

muscle naming methods

origin, insertion, action, location, fiber direction, size, shape

origin

where muscle starts

insertion

where muscle ends by attaching bone via tendon

tendon @ bone that moves

sternocleidomastoid muscle

bends neck & rotates head. named for points of origin

stern/o

breastbone

cleid/o

collarbone, clavicle

action example

flexor carpi radialis

flexor carpi radialis

decreasing angle of wrist in forearm

location examples

pectoralis major, tibalis anterior

pectoralis major

anterior chest

tibalis anterior

infront over tibia

where shin splint issues come from

fiber directions

oblique, rectus, transverse, sphincter

oblique

45 degree angle

rectus

upright

sphincter

circular

constricting/regulating muscle

transverse

left to right

size & shape examples

glueteus maximus, deltoid

gluteus maximus

large butt cheek

frontalis

front of forehead, lowers brows

masseter

moves jaw, chew

masticate

chew

buccinator

depresses cheek

buc/o

cheek

buccal

chew, whistle

oculi-

eye

orbicularis

around, orbit, circular

oris

mouth

pect major

adducts (towards) arm b/c of tendon inserts on humerus

external obliques

flex & rotate spondyl/o & torso

spondyl/o

vertebrae/spine

rectus abdominus

supports spine minor role in breathing

internal obllique

fiber directions 45 degrees towards midline

external oblique

fiber directions 45 degrees away from midline

mastoid process

bone behind and below ear

deltoid

triangular , shoulder cap, arm abduction

trapezius

moves head & shoulder blades, supports head upright, spinal flexion

connects to occipital

quadriceps femoris

4, location/bone

extends leg @ knee

hamstring group

posterior, knee flexion, decrease joint angle

calcaneus

heel bone

patella tendon

on knee in quadriceps

gastrocnemius

calf

bends foot down (plantar flexion), achilles tendon, attaches it to heel/calcaneus

intermedius

between

medialis

mid location

lateralis

side location

faciitis

inflamed fascia, protective tissue covering muscle & tendons

fascia

protective tissue covering muscle & tendons

fibromyalgia

chronic (longterm) condition of muscle & joint pain → need pain relievers

analgasic

way to describe pain relievers. ex: ibuprofen

-algesia

pain

-algia

pain

myocele

protrusion of muscle thru a tear in fascia into abnormal area

hernia

-cele

hernia

protrusion of muscle thru a tear in fascia into abnormal area

myorrhexis

muscle + rupture

sarcopenia

decrease of muscle/connective tissue mass & strength with aging

sarco

muscle/connective tissue

atrophy

lack nourishment or nerve damage to muscle → wastes away

-wheelchair, cast

don’t use it? lose it

atonia

lack tone

hypotonia

less/decreased tone

can affect posture, digestion, continence issues

incontinence

can’t control #1 or #2

dystonia

abnormal tone, causes impairment of voluntary muscle; torsion dystonia

torsion dystonia

a rare, chronic neurological movement disorder characterized by involuntary, sustained, or repetitive muscle contractions that cause twisting and abnormal postures

ataxia

lack coordination of voluntary (can control) muscles = skeletal somatic

soma-

body

tax-

coordination

spasm

sudden, involuntary contraction of 1 or more muscles

para-

near, beside, adjacent

juxta-

near, beside, adjacent

peri-

near, beside, adjacent OR around

hemi-

half

semi-

half

morph/o

root for form/shape

contra-, anti-

against, opposite

sprain

overstretch and inflammation of muscle & tendon, ligament damage

bradykinesia

slow movement → parkinson → muscle dystrophy

brady-

slow

tachy-

fast

kines-

movement

hyperkinesia

excessive movement