Articular Cartilage Flashcards
Elastic cartilage
External ear
Fibrous cartilage
Larynx, intervertebral discs
Hyaline cartilage
Joints
Thicker collagen, found in bone, tendon, ligament, and skin
Type I
Thinner fibril collagen (200nm) found in AC
Type II
AC provides ___
Low friction surface, shock absorption, distribute loads between opposing bones
T/F: AC has nerves and blood
False
Thickness of AC
1-6 mm
AC is lubricated with
Synovial fluid
Functional cells in AC
Chondrocytes
Backbone for PGs
Hyaluranic acid
Resist compression stresses and branch off of HA
Proteoglycans
Chondrocytes are found in larger numbers near
Articular surface and bone
Large protein-polysaccharide molecules with a protein core and glycosaminoglycans attached
Proteoglycans
Collagen ___ with PGs
Cross links
Near Articular surface, ___ are low and ___ is high
PGs; water
Near subchondral bone, ___ is low and ___ are high
Water; PGs
Collagen is strong under
Tension
4 zones between articular surface and subchondral bone
Superficial tangential, middle, deep, (tide mark), calcified cartilage
High water, low PG, fine collagen aligned parallel to surface, elongated chondrocytes parallel to surface
Superficial tangential zone
Thicker collagen at 45 deg, rounded chondrocytes
Middle zone
Thick collagen perpendicular to surface, high PG, low water, spherical chondrocytes in columns
Deep zone
Separates AC from subchondral bone, tidemark
Calcified cartilage zone
Breakdown of AC
Osteoarthritis
As load increases, ___ decreases
Permeability
AC has what 2 phases
Solid and fluid, elastic and viscous
PGs help with ___ stiffness
Compressive
How does AC react under impact load
Acts as a solid, PGs and collagen resist the load
Types of tests for AC
Indentation, unconfined, confined
