Unit 2 Concept 2: Movement

joints

synarthrosis

most stable, non-moving functional classification (part of skull that protects brain)

amphiarthrosis

slightly moving functional classification (where pubic bones meet in pelvis)

diarthrosis

freely moving functional classification (knee, elbow, mostly in limbs)

suture

fibrous joints that hold the bones in the skull together

syndesmosis

fibrous joints (ligaments) that hold the fibula and tibia together

gomphosis

fibrous joints that hold teeth in their sockets

symphysis

slightly movable joint made of fibrocartilaginous intervertebral discs that act as shock absorbers between vertebrae (cartilaginous joint)

gliding

when relatively flat bone surfaces move past each other, cause little rotation/angular movement (carpals, tarsals)

flexion

decreases angle between two structures as they move closer together

extension

increases the angle between two structures as they straighten/move farther apart

hyperextension

going beyond anatomical position

rotation

bone moving around a central axis

supination

rotation of radius in lateral direction (thumbs out, palms up)

pronation

rotation of radius in medial direction (thumbs in, palms down)

adduction

structure added back towards midline reference point

abduction

structure moved away from its midline reference point

opposition

touching the tips of your fingers with your thumb

circumduction

creating a circular/conical motion using flexion, extension, abduction, adduction

elevation

movement of a body part in a superior direction

depression

movement of a body part in an inferior direction

protraction

scapulae move forward and to the side

retraction

scapulae move backward and to the side

dorsiflexion

back/upper side of the foot moves towards shin, decreases angle

plantarflexion

sole of foot move towards calf, decreases angle

inversion

sole turns towards the body’s midline

eversion

sole turns away from body’s midline

isotonic

cause a change in length of the muscles (push-ups)

isometric

no change in muscle length (planks)

insertion

movable bone during muscle contraction

origin

bone that moves less or not at all

fibrous joints

mostly immovable, connect bones with collagen fibers of dense connective tissue (sutures)

cartilaginous joints

connect bones using cartilage, can be rigid but slightly movable (synchondrosis)

synovial joints

connect bones with dense connective tissue and a fluid filled joint cavity, freely movable