Development of Cartilage and Bone

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Stephen E. Fish, Ph.D. Mitchell L. Berk,
Ph.D. Marshall University J. C. E. School of
Medicine
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Note to instructors I use these PowerPoint
slides in histology lectures that I give to first
year medical students. Copy the slides, or just
the images into your own teaching media. We all
know that teaching science often requires
compromises and simplification for specific
student populations, or the requirements of a
specific course. Please feel free to offer
suggestions for improvements, corrections, or
additional illustrations. I would be pleased to
hear from anyone who finds my work useful, and am
always willing to make it better. Also, the
images have been compressed to screen resolution
to keep PowerPoint file size down, and I can
provide them at any resolution. Contact me about
the illustrations and Mitchell L. Berk about the
photomicrographs. Stephen E. Fish,
Ph.D. Fish_at_Marshall.edu Berk_at_Marshall.edu
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Development of Cartilage Bone
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Cartilage development A
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Cartilage development B
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Cartilage development C
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Cartilage development D
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Cartilage development E
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Cartilage development F
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Early cartilage growing fast
Fibrous perichondrium
Cells producing matrix beginning to divide
Cellular (chondrogenic) perichondrium
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Maturing cartilage
Staining of concentrated GAGS makes territorial
matrix
Division stopped leaving isogenic Cell nests
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Rules for bonedevelopment, growth, repair

• Bone stem cells love blood cartilage stem cells
  hate blood
• Osteoblasts make bone within about 200 µm of
  capillaries surround them
• Cartilage lives by diffusion, if it is blocked
  chondrocytes die cartilage calcifies
• Dying calcified cartilage initiates bone
  formation
• Osteoclasts oppose osteoblasts

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Intramembranous Ossification A
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Intramembranous Ossification B
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Intramembranous Ossification C
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Intramembranous Ossification D
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Intramembranous Ossification E
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Intramembranous Ossification F
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The dense immature woven bone cortex is remodeled
into mature compact bone
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Intramembraneous periosteal ossification
continues on the outside of bones A

• The cellular periosteum is a remnant of
  mesenchymal membrane
• Addition of bone on the outside is done in
  relation to capillaries

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Intramembraneous periosteal ossification B
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Intramembraneous periosteal ossification C
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Intramembraneous periosteal ossification D
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Growth of the baby head A

• Fontenelles (soft spots) is mesenchymal membrane
  with fibrous periosteum
• Growth in head size requires enlargement of skull
  plates

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Growth of the baby head B

• Growth on the plate edges surface is by
  intramembranous periosteal ossification
• Thickness and curvature changes also require
  remodeling (osteoblast vs. osteoclast)

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The adult skull used for the drawing
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Endochondral ossification A
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Endochondral ossification B
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Endochondral ossification C
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Endochondral ossification D
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Endochondral ossification E
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Endochondral ossification F Detail on the
epiphyseal growth plate
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Endochondral ossification G
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Left hand 2ond digit Proximal phalanx
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Developing finger bone
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The cartilage growth plate metaphysis
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The cartilage growth plate metaphysis
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Calcified cartilage
Bone
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When a bone breaks A
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When a bone breaks B
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When a bone breaks C The repair process starts
with cartilage
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When a bone breaks D New bone grows
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When a bone breaks E Cartilage dies
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When a bone breaks F Cartilage dies bone grows
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When a bone breaks G The ends are welded together
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When a bone breaks H New bone is remodeled
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Sherman says
My bone!