Set 5: Lecture 5 - Cartilage and Bone Structure

Skeletal cartilage characteristics

High water content, flexible, avascular, surrounded by perichondrium

Appositional growth

Cartilage growth from outside, making it wider

Interstitial growth

Cartilage growth from inside, making it longer

Axial skeleton function

Protection of brain, spinal cord, and thoracic organs

Appendicular skeleton function

Movement through limbs and girdles

Long bone example

Femur; acts as lever, supports weight

Short bone example

Carpal bone; designed for strength and stability

Flat bone example

Scapula; serves as protector and muscle attachment point

Irregular bone example

Vertebra; has complex shape with various functions

Crest

Prominent ridge bone marking for muscle/ligament attachment

Trochanter

Very large blunt irregular projection bone marking

Spine

Pointed projection bone marking

Tuberosity

Large rough and rounded projection bone marking

Head

Rounded articulated projection with narrower neck

Foramen

Round or oval opening in bone for vessels/nerves

Epiphyses

Ends of long bone with thin compact bone and thick spongy bone

Diaphysis

Shaft of long bone with thick compact bone and medullary cavity

Periosteum

Outer membrane of bone with fibrous and osteogenic layers

Spongy bone

Honeycomb lattice structure found in epiphyses

Compact bone

Dense bone with bundled osteons forming outer layer

Osteon structure

Concentric cylinders with central (Haversian) canal and perforating (Volkmann) canals

Organic components of bone (35%)

Bone cells (osteoblasts, osteocytes, osteoclasts) and collagen fibers

Inorganic components of bone (65%)

Hydroxyapatites (calcium phosphate) providing hardness and strength