General anatomy on what is bone, type of bone and briefly describe in presentation

1. Bones
&
Types
Presenter: Dr. Rahul Sharma
Bpt ( JMI)
MSc.ANATOMY
AIIMS, RISHIKESH
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2. Objectives
• Introduction
• Skeleton
• Bone
• Classifications
• 1 Clinical vignette
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3. Skeleton
Form a rigid frame work of body
Includes
Bones
Cartilages
Joints
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5. Axial skeleton
•Skull
1. Cranium
2. Facial bone
• Ear ossicles
• Hyoid bone
• Sternum
• Vertebral
column
• Rib cage
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6. Appendicular
skeleton
• Upper limb +
pectoral girdle
• Lower limb +
pelvic girdle
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7. Bone
• Os (Latin)
• Osteon ( Greek)
Hard structure , form rigid framework of body
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8. Structurally
Highly vascular mineral connective tissue
• 2/3 Made up of
• Organic component
(make it tough & resilient)
• Inorganic salts
(Make it hard and rigid)
• 1/3 made up of
connective tissue
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9. Characteristics
• Living tissue
• Highly vascular
• Supply by nerve and blood vessel
• Constant turn over of its calcium content
• Show pattern of growth
• Subjected to disease & heal after fracture
• Regenerative power
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10. Microscopic Structure
• Cells
• Ground substance + fibre , form the
intercellular substance or matrix
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11. Cells
Osteoproginator
cells
• Osteoblast
• Osteocytes
• Osteoclast
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12. Ground substance or Matrix
3. Type 1 collagen fibre
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13. Classification
• Acc to shape of bone
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14. • Long bone
Mid elongated shaft (diaphysis)
Two expanded ends (epiphyses)
Central inner medullary cavity
• Typical long bones
humerus, radius, ulna, femur, tibia,
fibula;
• Miniature long bones have only one epiphysis
e.g. metacarpals, metatarsals and phalanges; and
• Modified long bones have no medullary cavity e.g clavicle
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15. • Short bones:
Shape is usually cuboid, cuneiform,
Trapezoid or scaphoid.
Examples: tarsal and carpal bones
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16. • Flat bones
Shallow plates
Form boundaries of body cavities.
Examples:
Vault of skull, ribs,
sternum & scapula
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17. • Sesamoid bone
Bony nodules found embedded in tendons or joint
capsules.
No periosteum and ossify after birth
Functions of sesamoid bones are:
(a) To resist pressure;
(b) To minimise friction;
(c) To alter direction of pull of muscle
(d) To maintain local circulation.
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18. • Pneumatic bone
Irregular bones contain large air spaces lined by
epithelium
examples: maxilla, sphenoid, ethmoid.
Function:-
Make skull light in weight,
Help in resonance of voice,
Act as air conditioning chambers for inspired air
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19. • Accessory bone (supernumerary bone)
Not always present .
Occur as ununited epiphyses
Developed from extra-centres of ossification.
Examples: Sutural bones, os trigonum
(lateral tubercle of talus),os vesalianum
(tuberosity of 5th metatarsal)
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20. Structural classification
Macroscopically,
• Compact bone
• Cancellous bone
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21. Compact bone consist of
• Lamella of collagenous sheet
• Haversian system or osteon
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22. Cancellous bone/ spongy bone
• Meshwork of bony spicules.
• Present interconnected rods and plates of bones
• don’t form haversian system
• Architecture of cancellous bone is depend upon
trajectory theory (Wolf’s law)
Pressure lamellae Tension lamellae
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24. Microscopically
Classification is based on arrangement of different
component in matrix
• Woven bone – Collagen fasiscle and bony crystal
arranged in mesh network, like woven fabric e.g, callus
bone , young fetal bone
• Lamellar bone- Mineralized matrix arranged in layer of
thin sheet e.g. All adult bone
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25. Gross structure
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26. Epiphyses
• Type of epiphyses
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27. Developmental classification
Membranous bone
• Develop from membranous ossification
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29. Cartilagineous bone
• Develop from cartilagineous ossification
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30. Intra-cartilagnious ossification
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31. Clinical Vignettes
• Many of the joints present in midline are
secondary cartilaginous joint in axial skeleton,
what type of joint is xiphisternal joint?
What type of bone is sternum?
• Synchondrosis joint
• flat bone
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32. References
• Vishram Singh general anatomy e.2014
• BD Chaurasia_s Handbook of General
Anatomy, 4th Edition
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