Da Joints Flashcards
What are the functions of joints
They give the skeleton mobility and hold it together
What are the three structural classifications of articulations
Fibrous, cartilaginous, synovial
What are the three functional classifications of articulations
Synarthroses (immovable), Amphiarthroses (slightly moveable), and Diarthroses (freely moveable)
What are the properties of fibrous articulations
Bones joined by dense fibrous CT, no joint cavity, most are immovable
What are the three types of fibrous articulations
Sutures, syndesmoses, gomphoses
Where are sutures found
The skull. They allow for growth during youth and then ossify and fuse
Where are syndesmoses found
Anywhere joints are held together by a ligament, such as the interosseous membrane connecting the radius and ulna
Where are gomphoses found
The teeth in alveolar sockets
What are the properties of cartilaginous articulations
No joint cavity, slightly movable
What are the two types of cartilaginous articulations
Synchondroses and symphyses
Where are synchondroses located
In bars or plates of hyaline cartilage that unite bones, such as the temporary epiphyseal plate
Where are symphyses located
Anywhere fibrocartilage unites bone, such as the intervertebral joints
What are the properties of synovial articulations (six)
Articular cartilage, joint (synovial) cavity, articular (joint) capsule, synovial fluid, different types of reinforcing ligaments, nerves and blood vessels
What is the function of articular cartilage and what does it consist of
Prevents crushing of bone ends, hyaline cartilage
What is the structure of the articular cavity
Two layers thick, external fibrous layer is made of dense irregular CT and the inner synovial membrane is made of loose CT that makes synovial fluid
What are the properties of synovial fluid
It’s a filtrate of plasma and hyaluronic acid that lubricates and nourishes articular cartilage. Also contains phagocytes to remove microbes and debris
What are the three different types of reinforcing ligaments
Capsular (thickened part of fibrous layer), extracapsular (outside the capsule), intracapsular (deep to the capsule, covered by synovial membrane)
What are the functions of the nerves and blood vessels in synovial joints
Proprioception (perception and awareness of the position and movement of the body in space), nerves detect pain & monitor joint position and stretch, capillary beds supply filtrate for synovial fluid
Other features of synovial joints (two)
Fatty pads (cushioning between fibrous layer of capsule and synovial membrane or bone) and articular discs (menisci). Fibrocartilage separate articular surfaces to improve fit of bone ends, stabilize joint, and reduce wear and tear
What are the three factors that dictate joint stability
Shape of articular surface, ligament number and location, and muscle tone
Origin
Attachment to immovable bone
Insertion
Attachment to movable bone
Nonaxial
Slipping movements only
Uniaxial
Movement in one plane
Biaxial
Movement in two planes
Multiaxial
Movement in or around all three planes
