Cartilage Flashcards
3 types of cartilage
- Hyaline
- Elastic,
- Fibrocartilage
Hyaline cartilage fxn and location
- Aides in sliding within joints and provides a model for later bone growth
- Airway structural support including the larynx and cricoid cartilage in trachea
Fibrocartilage overview
- Cells lined up in rows
- More collagen fiber content than others
- No perichondrium
Fibrocartilage fxn and location
- Provides cushioning, strength and resists tearing and compression
- within IVD, meniscus, and pubic symp
Elastic cartilage
- Elastin fibers as part of the ECM
- Provides flexible shape and support to soft tissues
- External ear, epiglottis
Chondrocytes are embedded
-in lacunae, pockets of ECM
Isogenous groups
-multiple chondrocytes in the same lacunae derived from the same mother cell
Territorial matrix
ECM around lacunae
Intraterritorial matrix
-ECM between perichondrium and chondrocyte layer
Cartilage fibers
- Bonds between type II collagen, hyaluronan, and sulfates GAG on dense proteoglycans
- All cartilage types are relatively a vascular, receiving nutrients by diffusion from surrounding CT
Most important role of collagen
Shock absorber
Cartilage development
- Mesenchyme proliferates and differentiates into chondrocytes
- Chondrocytes produce ECM
- Cells disperse within ECM
- Individual chondrocytes undergo mitosis to form isogenous cell groups
Articular Cartilage
- Hyaline cartilage forms it
- Smooth, Low-friction interface
- Synovial fluid allows nutrients and waste product to circulate between non-vascular cartilage and CT vasculature
- Articular Cartilage has low metabolic activity, so heals slowly and slow turn over
Why does Articular cartilage heal slowly
-Low metabolic activity
What stimulates growth and inhibits growth of cartilage
- Stim: Growth hormone and thyroid hormone
- Inhibit: adrenal stress hormones; that’s why being stressed is bad for cartilage healing
Elastic cartilage body locations
- External ear
- Epiglottis
- Eustachian tube
- Parts of Larynx
Elastic cartilage has what types of fibers and stain darkly with what
-Elastin fibers stain darkly with trichrome
Fibrocartilage cells
- Line up in isogenic chondrocyte arrays
- Collagen fibers are arranged in such a way that tensile strength is maximized
Strongest and most abundant collagen found in what cartilage
Fibrocartilage
Osteoarthritis
- Chronic that occurs with aging
- Gradual loss of hyaline cartilage lining within joints
Osteoarthritis pathophys
- Fragments within Articular cartilage trigger secretion of enzymes like matrix matellaproteinases from macrophages in adjacent tissues
- Pro-inflammatory factors exacerbate damage, causing pain
Osteoarthritis and age-related hyaline cartilage degen
Calcification, especially in the costal cartilage attachment to ribs
Tumors of Cartilage
- Benign chondroma: slow growing
- Malignant chondrosarcomas: cells produce normal matrix components. They seldom metastasize and are generally removed surgically
