joints: WHY DO THEY CRACK SO MUCH??

IM NOT EVEN THAT OLD MAN

fibrous joints (structural classification)

bones held together by connective tissues

• between bones in close contact

• ex: skull sutures/teeth

• no joint cavity

cartilaginous joints(structural classification)

bones held together by cartilage

• ex: pubic symphysis and intervertebral discs

• no joint cavity

synovial joints(structural classification)

bones separated by a joint cavity

• most complex

• allow free movement

• ex: hip, knee, shoulder

synarthrotic joints (functional classification)

immovable

• calcified, fibrous connection between bones,

• primarily meant for protection of certain vital organs

• ex: sutures of the cranium

amphiarthrotic joints (functional classification)

slightly moveable

• cartilagious joints

• limited/restricted movement

• ex: intervertebral disc joints

diarthrotic joints (functional classification)

freely moveable

• synovial joints

• permit movement in a variety of diff directions

ball and socket joint:

• • multiaxial

  • nearly 360 degree range of motion

  • circumduction

hinge joint

• uniaxial

• back and forth in one plane of motion

• flexion & extension

pivot joint

• uniaxial

• one bone moves in a circular motion around another stationary bone

• rotation

saddle joint

• biaxial

• twiddling of the thumbs and oppositional movement of thumbs

gliding planar joint

• nonaxial

• flat articulating surfaces that slide/rub/glide alongside each other

ellipsoidal/condylar joint

• biaxial

• one bone has an egg shaped articular surface fitting into another bone’s oval/concave surface