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The image analysis captured most of the content but was cut off partway through Section 19. Here is the full, organized transcription of your Bone - Complete Notes:

BONE - COMPLETE NOTES

Page 1

1. Compact Bone Structure

  • Forms the outer surface of bones.
  • Composed of osteons (Haversian systems).
  • Each osteon = central (Haversian) canal + concentric lamellae of calcified matrix.
  • Lacunae with osteocytes between lamellae.
  • Canaliculi connect lacunae to central canal.
  • Perforating (Volkmann's) canals connect osteons.
  • Provides strength & protects inner parts.
Diagram labels: osteon, concentric lamellae, lacuna (with osteocyte), canaliculi, central canal, perforating canal

2. Spongy Bone

  • Inner portion, lining marrow cavity.
  • Honeycomb appearance of trabeculae & spicules.
  • Designed to withstand stress.
  • Trabeculae = tiny bone struts/plates.
  • Irregular lamellae, contain osteocytes but no osteons per se.
  • Receive nutrients from marrow tissue.
Diagram labels: trabeculae, marrow space

3. Spongy Bone Histology

  • Irregular bony trabeculae.
  • Covered by endosteum.
  • Spaces filled with red or yellow marrow.
  • No osteons; nutrients diffuse from marrow.
Diagram labels: trabecula, osteocytes, endosteum, marrow
Note: Spongy bone forms interior of epiphyses in long bones. Diaphysis (shaft) = compact bone around marrow cavity.

Page 2

4. Flat Bone Structure

  • Two layers of compact bone (outer & inner tables) sandwich spongy bone (diploë).
  • e.g. skull bones, sternum, ribs, scapula.
Diagram labels: outer compact, diploë (spongy), inner compact

5. Bone Structure (Long Bone)

  1. Articular cartilage - Hyaline cartilage on joint surfaces. Fibrocartilage in menisci of knee.
  2. Epiphyses - Ends of long bones (one at each end).
  3. Epiphyseal line - Remnant of growth plate (epiphyseal plate).
  4. Diaphysis - Shaft between epiphyses. Contains medullary cavity; yellow marrow in adults.
  5. Periosteum - Tough outer connective tissue. 2 layers: outer fibrous CT, inner osteogenic (osteoblasts, osteoclasts). Rich in blood vessels, nerves. Attached by Sharpey's fibers.
  6. Endosteum - Lines inner bone cavities. Contains osteoblasts & osteoclasts. Osteogenic.
  7. Sharpey's fibers - Collagen bundles that anchor periosteum to bone.
Diagram labels: Articular cartilage, Epiphysis, Spongy bone, Epiphyseal line, Compact bone, Medullary cavity, Diaphysis

6. Bone Blood Supply

  • Highly vascular.
  • 1. Nutrient arteries - enter via nutrient foramen (diaphysis) → medullary cavity.
  • 2. Periosteal arteries - supply periosteum & outer compact bone.
  • 3. Metaphyseal & epiphyseal arteries - supply epiphyses → form rich anastomoses.
Diagram labels: nutrient artery, nutrient foramen

Page 3

7. Bone Marrow

  • Yellow marrow - in medullary cavity of long bones. Not hematopoietic in adults. Made mainly of fat.
  • Red marrow - in axial skeleton, girdles & epiphyses of femur & humerus. Active hematopoietically.
Diagram labels: red marrow, yellow marrow

8. Bone Tissue

  • Two types: (a) Compact, (b) Spongy

9. Bone Cells

  1. Osteoclasts - Bone destroying cells (C = chewing)
  2. Osteoblasts - Bone forming cells (B = building)
  3. Osteocytes - Mature bone cells, spider shaped; maintain bone tissue.

10. Chemical Composition

  • Majority = inorganic molecules (Ca & phosphate).
  • Form hydroxyapatite: Ca₁₀(PO₄)₆(OH)₂
  • Gives hardness & strength.
  • Collagen fibers (type I) form matrix → elasticity & flexibility.

11. Bone Matrix

Organic (30-40%)Inorganic (60-70%)
Collagen fibers (type I)Calcium phosphate salts (Hydroxyapatite)
ProteoglycansCalcium carbonate
Glycosaminoglycans
Glycoproteins
→ Strong yet flexible bone.

Page 4

12. Bone Growth & Development

  • Bone derived from hyaline cartilage - interstitial ossification (within cartilage) or appositional growth (from outside).

13. Bone Development (Ossification/Osteogenesis)

  • Process of forming new bone.
  • Two methods:
    1. Endochondral ossification
    2. Intramembranous ossification

14. Endochondral vs Intramembranous Ossification

Endochondral (Cartilage model replaced by bone)Intramembranous
Involves cartilage intermediateBone replaces fibrous membrane
Forms most bones (long bones, vertebrae, pelvis)Forms flat bones (skull, sternum, mandible, clavicle)
Growth in length of long bonesOsteoblasts form bone directly
Fracture healingGrowth by appositional & interstitial
  • Appositional growth - adding layers outside (bone width).
  • Interstitial growth - growth from within (bone length).
  • Long bones develop by both methods.

15. Endochondral Ossification - 3 Sites

  1. Primary ossification center - in diaphysis (during fetal life).
  2. Metaphysis - region between epiphysis & diaphysis.
  3. Secondary ossification center - in epiphysis (at/after birth).
Diagram labels: secondary ossification center, metaphysis, primary ossification center

Page 5

16. Epiphyseal (Growth Plate) - 5 Zones

  1. Zone of resting cartilage
  2. Zone of cartilage proliferation
  3. Zone of hypertrophic cartilage
  4. Zone of calcified cartilage
  5. Zone of ossification

17. Bone Growth

  • Increase in length - interstitial growth at epiphyseal plate. Cartilage grows on epiphyseal side, replaced by bone on diaphyseal side.
  • Increase in width - appositional growth. Osteoblasts add layers outside; osteoclasts remove some inside to maintain marrow cavity.

18. Control of Bone Growth

  • Minerals - Ca, P essential.
  • Vitamins - A, C, D.
  • Hormones - GH, T3/T4, sex steroids (estrogen, testosterone).
  • Proper nutrition & exercise important.

19. Factors Affecting Bone Growth

A. Minerals

MineralRole
CalciumMakes matrix hard. Hypocalcemia/Hypercalcemia.
PhosphorusMakes matrix hard.
MagnesiumDeficiency inhibits osteoblasts.
BoronMay inhibit Ca loss, ↑ estrogen levels.
ManganeseInhibits formation of new bone.

B. Vitamins

VitaminRole
AControls activity & coordination of osteoblasts/osteoclasts.
B12May inhibit osteoblast activity.
CHelps maintain bone matrix (collagen). Deficiency → scurvy.
D (Calcitriol)Increases Ca absorption. Deficiency → Rickets (children), Osteomalacia (adults).

C. Hormones

HormoneRole
Growth Hormone (GH)Promotes general growth.
IGF (Insulin-like Growth Factor)Stimulates amino acid uptake & protein synthesis.
InsulinPromotes normal bone growth.
Thyroid Hormones (T3, T4)Promotes normal growth & maturity.
Estrogen & Testosterone↑ osteogenesis at puberty, responsible for gender differences.

D. Exercise

  • Mechanical stress stimulates bone formation.

20. Bone Remodeling

  • Adult bone constantly remodeled.
  • ~5-10% bone mass turned over each week.
  • Wolff's Law - shape of bone altered by mechanical forces.
  • Remodeling:
    1. Osteoclasts - resorb bone (ruffled border).
    2. Osteoblasts - form new bone.
  • Regulated by hormones: a. Parathyroid hormone - ↑ Ca absorption (↑ blood Ca). b. Calcitonin - ↓ Ca absorption (↓ blood Ca).

21. Osteoporosis

  • Imbalance: bone resorption > formation.
  • Up to 10% bone mass remodeled normally.
  • Trabecular bone more active → more affected.
  • Common fracture sites: wrist, hip, spine (high trabecular:cortical ratio).

22. Bone Markings & Landmarks

  • Processes - projections/levers (attachment), e.g. coronoid process.
  • Foramina - holes for vessels/nerves, e.g. foramen magnum.
  • Fissures - narrow slit-like openings, e.g. orbital fissure.
  • Sinuses - air-filled spaces, e.g. frontal sinus.
  • Articulations - joints between bones.
That covers all 22 sections across the 5 pages of your Bone Complete Notes, including all tables, diagram labels, and clinical correlations (osteoporosis, rickets, osteomalacia, scurvy).
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