Joints Flashcards
What are joints? How many joints are there?
where bones meet other bones; there are over 200 joints in the body
What are the three functional classes?
Synarthroses, Amphiarthroses, Diarthroses
Synarthroses; examples?
immovable joints; plates of skull fuse together
Amphiarthroses; examples?
slightly movable joints; connections between vertebrae in back
Diarthroses; examples?
freely movable joints; elbow
What are synovial joints?
diarthroses are filled with liquid called synovial fluid to help lubricate the joint; the fluid is held in by cartilage
What can happen to synovial fluid?
it can become infected (septic arthritis) or filled with blood (hemorrhagic arthritis); arthritis means joint inflammation
What are cracking joints?
popping of small air bubbles that forms in synovial fluid when pressure quickly changes- not linked to arthritis or joint problems
What are the 6 shapes of diarthrotic joints?
plane, hinge, pivot, condyloid, saddle, ball and socket
What are plane joints and where are the found?
allow gliding or rotating motion; two flat surfaces against each other; found between carpals and tarsals
What are hinge joints and what are some examples?
allow movement cross one plane; cylinder “rolls” in U shape; elbow, knee, joints between phalanges
What are pivot joints and give examples.
allows rotation around one place; a circle in a bigger circle (wrench/circle); radius/ulna, top two vertebrae in of neck
What are condyloid joints and give examples.
allows front/back and side/side movement; egg in socket; proximal phalanx/metacarpal
What are saddle joints and give examples.
allows front/back and side/side movement (but not easily both together); looks like two saddles sitting on each other; joint between first metacarpal and carpal that gives us opposable thumbs
What are ball and socket joints and give examples.
allows motion in full circle, plus rotation; humerus in shoulder, femur in hip
