Cartilage & bone, mbbs 1st year

5,185 views

Published on

for 1st year mbbs students

Published in: Education
1 Comment
5 Likes
Statistics
Notes
No Downloads
Views
Total views
5,185
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
317
Comments
1
Likes
5
Embeds 0
No embeds

No notes for slide

Cartilage & bone, mbbs 1st year

  1. 1. Histology of Cartilage
  2. 2. CARTILAGE
  3. 3. CARTILAGE
  4. 4. CARTILAGE
  5. 5. Cartilage <ul><li>General features: </li></ul><ul><li>Cells of cartilage – chondrocytes. </li></ul><ul><li>No blood vessels or lymphatics. </li></ul><ul><li>No nerves. </li></ul><ul><li>Surrounded by a fibrous membrane called perichondrium. </li></ul><ul><li>When cartilage calcifies, chondrocytes die & the cartilage is replaced by bone. </li></ul>
  6. 6. Hyaline Cartilage <ul><li>Features: </li></ul><ul><li>Intercellular substance is homogenous. </li></ul><ul><li>Contains numerous collagen fibers. </li></ul><ul><li>Cells are usually present in groups (of two or more), called cell nests or isogenous cell groups. </li></ul><ul><li>Distribution: </li></ul><ul><li>Costal cartilages, </li></ul><ul><li>Articular cartilage, </li></ul><ul><li>Thyroid, cricoid & arytenoid cartilages, </li></ul><ul><li>Nasal septum & lateral wall of nose, </li></ul><ul><li>Epiphyseal plate of cartilage. </li></ul>
  7. 7. Elastic Cartilage <ul><li>Matrix contains elastic fibers that form a network. </li></ul><ul><li>Distributions: </li></ul><ul><ul><li>Auricle or pinna, </li></ul></ul><ul><ul><li>Lateral part of EAM, </li></ul></ul><ul><ul><li>Medial part of auditory tube, </li></ul></ul><ul><ul><li>Epiglottis, </li></ul></ul><ul><ul><li>Corniculate & </li></ul></ul><ul><ul><li>Cuneiform. </li></ul></ul>
  8. 8. Fibrocartilage <ul><li>Numerous collagen bundles. </li></ul><ul><li>No perichondrium over the cartilage. </li></ul><ul><li>Distributions: </li></ul><ul><li>Intervertebral discs, </li></ul><ul><li>Pubic symphysis, </li></ul><ul><li>Manubriosternal joint, </li></ul><ul><li>Articular discs – TMJ, sternoclavicular joint, </li></ul><ul><li>Glenoidal labrum & acetabular labrum. </li></ul>
  9. 9. BONE - I
  10. 10. Functions of bone <ul><li>Give shape & support to the body & resist all forms of stress. </li></ul><ul><li>Provide surface for the attachment of muscles, tendons, ligaments, etc. </li></ul><ul><li>Serve as levers for muscular actions. </li></ul><ul><li>Protect visceral organs. </li></ul><ul><li>Bone marrow manufactures blood cells. </li></ul><ul><li>Store 97% of the body calcium & phosphorus. </li></ul><ul><li>Bone marrow contains R-E cells. </li></ul><ul><li>Paranasal air sinuses affect the timber of the voice </li></ul>
  11. 11. Classification of Bones <ul><li>According to shape: </li></ul><ul><li>Long bones: </li></ul><ul><li>Two ends called epiphysis & an intervening part diaphysis. </li></ul><ul><li>Contain nutrient foramen directed away from the growing end. </li></ul><ul><li>Typical long bone: Humerus, radius, ulna, femur, tibia, & fibula; </li></ul><ul><li>Miniature long bone: metacarpals, metatarsals & phalanges; & </li></ul><ul><li>Modified long bones: clavicle. </li></ul>
  12. 13. <ul><li>2. Short bones: </li></ul><ul><li>Shape is cuboid, cuneiform, trapezoid, or scaphoid. </li></ul><ul><li>Carpal & tarsal bones. </li></ul>
  13. 14. <ul><li>3. Flat bones: </li></ul><ul><ul><li>vault of the skull, ribs, sternum & scapula. </li></ul></ul><ul><li>4. Irregular bones: </li></ul><ul><ul><li>vertebrae, hip bone & bones in the base of the skull. </li></ul></ul>
  14. 15. <ul><li>5. Pneumatic bones: </li></ul><ul><ul><li>Maxilla, sphenoid, ethmoid, etc. </li></ul></ul>
  15. 16. <ul><li>6. Sesamoid bones: </li></ul><ul><li>patella, pissiform, fabella, etc. </li></ul><ul><li>Functions: </li></ul><ul><ul><li>To resist pressure; </li></ul></ul><ul><ul><li>To minimize friction; & </li></ul></ul><ul><ul><li>To alter the direction of pull of the muscle. </li></ul></ul><ul><li>7. Accessory bones: </li></ul><ul><li>Sutural bones </li></ul>
  16. 17. Developmental classification <ul><li>Membrane bone: </li></ul><ul><ul><li>Ossify in membrane, derived from mesenchymal condensations. </li></ul></ul><ul><ul><li>E.g. bone of vault of skull & facial bones. </li></ul></ul><ul><li>Cartilaginous bone: </li></ul><ul><ul><li>Ossify in cartilage & derived from the preformed cartilaginous models. </li></ul></ul><ul><ul><li>E.g. bones of limbs, vertebral column & thoracic cage. </li></ul></ul><ul><li>Membrano-cartilaginous bones: </li></ul><ul><ul><li>Partly in membrane & partly in cartilage. </li></ul></ul><ul><ul><li>E.g. clavicle, mandible, occipital, temporal, sphenoid. </li></ul></ul>
  17. 18. <ul><li>Regional classification: </li></ul><ul><ul><li>Axial skeleton: skull, vertebral column & ribs </li></ul></ul><ul><ul><li>Appendicular skeleton: bones of the limbs. </li></ul></ul><ul><li>Structural classification: </li></ul><ul><ul><li>Macroscopically </li></ul></ul><ul><ul><ul><ul><li>Compact bone, </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Cancellous bones </li></ul></ul></ul></ul><ul><ul><li>Microscopically </li></ul></ul><ul><ul><ul><ul><li>Lamellar bone, </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Fibrous bone, </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Dentine & </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Cement. </li></ul></ul></ul></ul>
  18. 20. Gross structure of an adult long bone <ul><li>Shaft: </li></ul><ul><ul><li>Periosteum </li></ul></ul><ul><ul><li>Cortex </li></ul></ul><ul><ul><li>Endosteum </li></ul></ul><ul><ul><li>Medullary cavity </li></ul></ul><ul><li>Two ends </li></ul>
  19. 21. <ul><li>Parts of a young bone: </li></ul><ul><li>Epiphysis: ends of bone, ossify from sec. centre of ossification. </li></ul><ul><li>Pressure epiphysis: head of femur, lower end of radius, etc. </li></ul><ul><li>Traction epiphysis: trochanters of femur & tubercles of humerus. </li></ul><ul><li>Atavistic epiphysis: coracoid process of scapula. </li></ul><ul><li>Aberrant epiphysis: epiphysis at the head of the first metacarpal & at the bases of other metacarpal bones </li></ul>
  20. 22. <ul><li>Parts of a young bone….. </li></ul><ul><li>Diaphysis: shaft of a long bone, ossify by primary centre of ossification. </li></ul><ul><li>Metaphysis : epiphysial end of diaphysis, zone of active growth. </li></ul><ul><li>Epiphysial plate of cartilage: separate epiphysis from diaphysis. it causes increased length of bone. </li></ul>
  21. 23. Blood supply of bones <ul><li>For long bone: </li></ul><ul><li>Epiphysial artery </li></ul><ul><li>Metaphysial artery </li></ul><ul><li>Periosteal artery </li></ul><ul><li>Nutrient artery </li></ul>
  22. 24. Histology of compact bone
  23. 25. Cells of Bone <ul><li>Osteoprogenitor cells: stem cells of mesenchymal origin that can proliferate & convert themselves into osteoblasts. </li></ul><ul><li>Osteoblasts: bone forming cells derived from osteoprogenitor cells & responsible for laying down the organic matrix of bone. </li></ul><ul><li>Osteocytes: cells of mature bone. </li></ul><ul><li>Osteoclasts: bone removing cells found in relation to surfaces where bone removing is taking place. </li></ul>
  24. 26. Cells of Bone
  25. 27. Histology of compact bone

×