Module 6 - Joints Flashcards
What is a joint?
joint = point of contact
- between bones
- between cartilages
- between teeth and bone
also called articulation
supported by ligaments, joint capsules, and by the attachment of surrounding muscles
How are joints classified?
joints are classified based on:
structure (what they’re made of)
- fibrous
- cartilaginous
- synovial
function (how much movement they provide)
- synarthroses (immovable)
- amphiarthroses (slightly movable)
- diarthroses (freely movable)
what are fibrous joints?
held closely together by fibrous connective tissue and provide little or no movement
examples include
a) suture joints of the skull
b) the tibia and fibula joint
c) tooth socket
What are suture joints?
part of fibrous joints
connect skull bones
immovable (synarthrotic)
What is interosseous membrane?
part of fibrous joints sheet of dense irregular CT between bones slightly movable (amphiarthrotic) similar joint between radius and ulna
What is a tooth joint?
part of fibrous joints
cone-shaped peg fits into a socket
immovable (synarthrotic)
What is cartilaginous joint?
held together by cartilage and permit little or no movement
examples:
a) the epiphyseal plate
b) the pubic symphysis
What is the epiphyseal plate?
part of cartilaginous joint
hyaline cartilage binds the epiphysis and diaphysis of the long bones
immovable (synarthrotic)
What is the pubic symphysis?
part of cartilaginous joint coxal bones are joined by a fibrocartilage disc slightly movable (amphiarthrotic)
What are synovial joints? what do they contain?
freely movable joint (diarthrotic) contains: -synovial cavity -synovial membrane -articular cartilage -joint capsule
most contain acessory ligaments, cartilage discs (menisci) and bursae
what is the joint capsule?
part of synovial joint
outer connective tissue layer that unites bones (connects to periosteum) and encloses the joint cavity
What is the synovial membrane?
part of synovial joint
secretes synovial fluid which lubricates joints and nourishes cartilage
what is the synovial cavity?
part of synovial joint
space between articulating bones, which contains synovial fluid and permits joint movement
what is the articular cartilage?
part of synovial joint
hyaline cartilage covers areas where bones articulate to reduce friction and absorb shock
what are menisci?
some synovial joints (ex. knee) contain fibrocartilage discs called menisci
What are bursae?
some synovial joints contain fluid filled sacs called bursae
they are located between bones and:
skin
ligaments
tendons
muscles
they help to reduce friction between moving parts
what are the 6 types of movements at synovial joints?
- flexion
- extension
- abduction
- adduction
- circumduction
- rotation
what are flexion and extension?
flexion = decrease in angle between two bones extension = increase in angle between two bones
demonstrate flexion and extension at the hip joint, knee joint and wrist joint
what are abduction and adduction?
abduction = the movement of a bone away from the midline adduction = the movement of a bone toward the midline, adding it back to the body
what is circumduction?
movement of the distal end of a part of the body in a circle
what is rotation?
bone revolves around its own longitudinal axis
What are the 6 different types of synovial joints?
*hinge
*pivot
*ball and socket
planar
condyloid
saddle
the shape of the joint determines the type of joint movement
*what is the hinge synovial joint?
- one bone fits into the concave surface of another
- allows flexion and extension
e. g elbow and knee joint
*what is the pivot synovial joint?
- a round bone surface articulates within a ring formed by another bone or ligament
- allows for rotation
e. g atlas - axis-joint, radius-ulna joint
