Articular Cartilage Flashcards
What are the cells that make up Hyalin Articular Cartilage?
Chondroblast/condrocyte
Articular cartilage = ___% cells, ____% ECM
1-5%, 99%
What are the 3 functions of Articular cartilage?
Decreases friction
Attenuates/distributes load through joint (decreases stress)
Cushions subchondral bone
What are the 4 zones of Articular cartilage?
Superficial
Transitional
Deep
Calcified
Articular Cartilage strengths (5)
Lubricated
Attached
Living
Nourished
Modifiable
Articular Cartilage strength: Lubricated
Synovial fluid and special surface molecules (superficial zone)
Articular Cartilage strength: Attached
Via mineralized deep layer to bone
Articular Cartilage strength: Living
Matrix allows diffusion to chondrocytes
Articular Cartilage strength: nourished
From synovial vessels via synovial fluid
Articular Cartilage strength: modifiable
Cells continue to make and selectively destroy ECM
Articular cartilage vulnerabilities (4)
Thin and easily worn away (ex. Osteoarthritis)
Relies on indirect nutrition
Only a few cells look after extensive matrix
Near a loose CT (the synovium) in which damaging defensive responses occur (ex. Gout, rheumatoid arthritis)
T/F: Cartilage is avascular
True; depends on synovial fluid for nutrients
T/F: Cartilage receives blood supply from bone.
False; cartilage receives NO blood supply from bone, depends on synovial fluid for nutrients
Articular Cartilage loading: Pros (3)
Nutrition/waste removal
Cyclical loading: stimulate collagen and other protein synthesis
Low or no additional risk from moderate running
Articular Cartilage Loading: Cons (6)
Acute alignment/meniscal damage
Patellar/ankle dislocations or osteochondral injuries
Chronic instability/congenital malalignment
Static loading
Poor alignment
Excessive loading
