UNIT 2

concept 2: movement

joints (articulations)

the meeting places between 2 or more bones

what do joints allow for your skeleton

mobility and hold it together

when do body movements happen

when muscles contract across joints, moving one bone toward another

what are the important connective tissues

ligaments and tendons

how are joints classified

structure and function

how are joints classified

what they do and how much movement they allow

how does the movement of a joint affect the stability

the less movable the joint, the more stable it is

what are the 3 types of functional joints

synarthroses

amphiarthroses

diarthroses

what is synarthroses

non moving joint

example of synarthroses

the part of the skull that protects the brain (cranium)

what is amphiarthroses

slightly moving joint

what is an example of amphiarthroses

where pubic bones meet in the pelvis

what is diarthroses

freely moving joint

example of diarthroses

knee and elbow joints, mainly in our limbs

3 types of structural joints

fibrous joints

cartilaginous joints

synovial joints

how are structural joints classified

what binds the bones together in the joint and if a cavity is present

what is a fibrous joint

connects bones with the collagen fibers of dense connective tissue

movement of a fibrous joint

mostly immovable

how are bones In the skill held together

SUTURES

how is the fibula and tibia in your lower leg held together by ligaments only

fibrous joints called syndesmosis

how are teeth embedded in their sockets

gomphoses

what are cartilaginous joints

connect bones with cartilage

movement and structure of a cartilaginous joint

rigid and slightly movable

what is synchondrosis

an immovable joint made of a bar/plate of hyaline cartilage between the sternum and first rib

what is symphysis

a slightly moveable joint made of fibrocartilaginous intervertebral discs that act as a shock absorbers between vertebrae

what is a synovial joint

connects bones with dense connective tissues and a fluid filled joint cavity

movement of a synovial joint

allows them to be freely movable

what are all synovial joints

diarthroses

what are the 6 special features of a synovial joint

articular cartilage

joint (articular) cavity

fibrous joint capsule

synovial fluid

band like ligaments

sensory nerve fibers and blood vessels

what is the purpose of the articular cartilage

covers the opposite bone surfaces

what does a fibrous joint (articular) capsule do

encloses the cavity

what does synovial fluid do

acts as a lubricant

purpose of bandlike ligaments

reinforcement

where is are the sensory nerve fibers and blood vessels

joint capsule and synovial membrane

what are the 6 configurations of synovial joints

gliding

hinge

pivot

condylar

saddle

ball and socket

gliding/plant joint

in the ankle and wrist

what is a gliding movement

when one flat bone surface glides or slips over another (back and fourth or side to side)

hinge joint

(like a door)

how much movement does a hinge joint allow

singular direction

flexion and extension

what kind of movement does hinge joints allow

angular

what is flexion

bending In a way that decreases the angle of the joint so the articulating bones get closer

what is extension

reverse of flexion

what is hyperextension

going beyond the anatomical position

where can you see hinge joints

elbow and interphalangeal finger joints

what kind of movement does a pivot allow

rotation and twisting movements back and fourth

what is pronation

twist/tun forward

what is supination

turn/twist backward

what is this an example of

pivot

example of pivot

where humerus meets radius and ulna at elbow

what is a condylar similar to

a pedestal with a joint on top

what kind of movement does condylar allow

flexion, extension

abduction, adduction

what is abduction

“moving away”

moving a limb away from the median plane, along the frontal plane

what is adduction

“moving toward”

opposite of abduction

example of condylar

in the wrist

condylar joint

what type of movement does a saddle joint allow

opposition

extension, flexion

abduction, adduction

example of saddle joint

thumb joint

saddle joint

what kind of movement does a ball and socket allow

lots of maneuverability

rotational

abduction, adduction

flexion, extension

what is a rotation

turning of the bone around its own long axis

example of ball and socket

shoulder and hip bones

ball and socket

other types of movements at different joints

circumduction

elevation and depression

protraction and retraction

dorsiflexion and plantar flexion

inversion and eversion

what is circumduction

moving a limb In a circle

(arm circles)

what is elevation and depression

lifting then lowering a body part superiorly

(shrugging shoulders)

what is an example protraction and retraction

sticking jaw out and back in

what is dorsiflexion and plantarflexion

lifting foot up and down at the ankle

what is inversion and eversion

turning the foot towards the midline of the body vs turning away from the midline of the body

what are muscle contractions

bones cant move without the joints that connect them and the muscles that stretch over those joints

when does movement occur

movement occurs when muscles contract

what do muscle contractions always do

pull not push

what are the 2 main types of muscle contractions

isotonic and isometric

what is isotonic movement

causes a change in the length of the muscles

example of isotonic movement

lifting a box or doing push ups

what are isometric muscle contractions

no change in length

example of isometric contractions

standing with good posture or doing a plank

what is insertion

the movable bone during a muscle contraction

what is origin

the bone that moves less or not at all

example of insertion and origin in muscle contraction

in a bicep curl, the radius is the insertion point and pulls towards the scapula, which is the origin