Joints Flashcards
Joints are also called
Articulations
Articulations have 2 functions. What are they?
1) They hold bones together securely
2) Give rigid skeleton mobility
Joints are classified in 2 ways. What are they?
1) Structurally
2) Functionally
Structurally classified joints
Fibrous, cartilaginous, and synovial joints based on whether fibrous tissue, cartilage, or a joint cavity separates the bony regions at the joint.
- Fibrous joints are immovable
- Synovial joints are freely moveable
- Cartilaginous joints are both moveable and slightly movable.
Functionally classified joints
Focuses the amount of movement allowed by the joint.
- Synarthrosis (immovable)
- Amphiarthrosis (slightly movable)
- Diarthrosis (freely movable)
Example of a synarthrosis joint
Skull
Example of Amphiarthrosis joint
Carpal bones in hand
Example of Diarthrosis joint
Limbs
Fibrous joints
Bones united with fibrous tissue
Ex: sutures of the skull = no movement.
In sutures, the irregular edges of bone interlock and are bounded tightly together by connective tissue fibers which allows no movement to occur.
Syndesmosis
The connective fibers are longer than those of sutures which allows a little movement.
Ex: joint connecting the distal ends of the tibia and the fibula
Cartilaginous joints
The bone ends are connected by cartilage. Slightly moveable (Amphiarthrotic) examples are the pubic symphysis of the pelvis and intervertebral joints of the spinal column (joined by discs of fibrocartilage).
Hyaline cartilage example is the epiphyseal plates or growing long bones and cartilaginous joints between the first ribs and the sternum.
Synovial joints
Joints in which the articulating bone ends are separated by a joint cavity containing synovial fluid.
Any joint with cartilage over it has synovial fluid
Every bone in the body except the __________ bone forms a joint with at least one other bone.
Hyoid
