Cartilage injury and Avascular necrosis Flashcards
Cartilage
A non vascular dense supporting connective tissue composed of chondrocytes and various fibres or ground substance.
What are the three different types of cartilage?
Hyaline
Elastic
Fibro
Hyaline cartilage is found where?
Hyaline - most common, found in the ribs, nose, larynx, trachea. Is a precursor of bone.
Fibrocartilage is found where?
Found in invertebral discs, joint capsules, ligaments.
Elastic cartilage is found where?
Found in the external ear, epiglottis and larynx.
What is the tide mark?
The tide mark is the junction between the vascular and avascular tissue of the cartilage.
Why is articular cartilage unique?
- Avascular
- Aneural
- Alymphatic
- Non-immunogenic
What type of collagen makes up articular cartilage?
Collagen type 2
What makes up articular cartilage?
- Chondrocytes - 5%
- Extracellular matrix
- Water - 75%
- Proteoglycans - 10 - 15%
- Collagen - type II; 10 - 20%
Function of articular cartilage:
Its principal function is to provide a smooth, lubricated surface for low friction articulation and to facilitate the transmission of loads to the underlying subchondral bone.
What is the function of hyaline cartilage?
Provides a stiff and flexible support - reduces friction between bony surfaces.
Function of elastic cartilage:
Provides support but allows deformation
Function of fibrocartilage:
Resists compression and limits movement.
What role does proteoglycan play in cartilage?
Very hydrophilic, takes water out of joint fluid and stores it in cartilage. Aggrecan most common.
Cartilage healing
Superficial can’t heal
Deep heals with fibrocartilage