Joints, Synovial Fluid and Cartilage Flashcards
What are the three structural classifications of joints?
Fibrous, cartilaginous and synovial
What type of joints are periodontal ligaments, cranial sutures and interosseus membranes?
Fibrous
What is the difference between a primary and a secondary cartilaginous joint?
A secondary cartilaginous joint contains hyaline and fibrocartilage, whereas a primary cartilaginous joint contains only hyaline cartilage
What is a synchondrosis?
Primary cartilaginous joint
What is a symphysis?
Secondary cartilaginous joint
What are the six types of synovial joint?
Plane Condylar (ellipsoid) Hinge Saddle Pivot Ball and socket
What is the superficial/tangential layer of hyaline cartilage made up of?
Flattened chondrocytes that produce collagen and glycoproteins (e.g. lubricin)
What is the transitional layer of hyaline cartilage made up of?
Round chondrocytes that produce proteoglycans such as aggrecan
What are glycoproteins?
Proteins to which oligosaccharide chains are attached, i.e. more a protein than a carbohydrate
What are proteoglycans?
Proteins that are heavily glycosylated (a protein core to which one or more GAGs attach), i.e. tend to be more carb than protein
What are glycosaminoglycans/GAGs?
Long unbranched polysaccharides, which are highly polar and thus attract water
What do type A synoviocytes (macrophage-like synovial cells) do?
Remove debris and contribute to synovial fluid production
What do type B synoviocytes (fibroblast-like synovial cells) do?
Main producer of synovial fluid
What are the functions of synovial fluid?
Nutrition of cartilage
Removal of waste products
Lubrication
What happens to joints during the aging process?
Viscosity of synovial fluid increases
- slower joint movements
- reduced lubrication
Water content of cartilage decreases
- reduced shock absorption
Less protection of articular surfaces and increased risk of damage
