Difference between revisions of "Bone Histology"

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== Terms ==
== Terms ==
[[File:Axial skeleton.jpg|thumb|Axial skeleton]]
[[File:Axial skeleton.jpg|thumb|Axial skeleton]]
[[File:Appendicular skeleton.jpg|thumb|Appendicular skeleto]]
[[File:Appendicular skeleton.jpg|thumb|Appendicular skeleton]]
* '''canaliculus''' - (plural, canaliculi) small channel in the bone matrix in which an osteocyte process lies and communicates with other osteocytes and the Haversian canal.
* '''canaliculus''' - (plural, canaliculi) small channel in the bone matrix in which an osteocyte process lies and communicates with other osteocytes and the Haversian canal.
* '''haematopoiesis''' (Greek, ''haima'' = "blood"; ''poiesis'' = "to make") the process of blood cell formation.
* '''haematopoiesis''' (Greek, ''haima'' = "blood"; ''poiesis'' = "to make") the process of blood cell formation.

Revision as of 18:01, 1 September 2011



Endochondral bone.jpg

Our adult skeleton forms from a larger number of developmental elements that are replaced and fuse. In development there are 2 separate signaling pathways for pattern formation and the formation of bone itself. Furthermore bone formation can be divided into 2 specific forms that occur in anatomically different regions. This practical class will describe the development and structure of bone and finish with a study of abnormalities associated with bone.

The image shown to the left shows a histological section through the developing lower limb at the level of a developing joint (knee), surrounding the developing bone are skeletal muscles and connective tissue of the limb.

Note: This current page contains both additional information and images to the practical class set. These are provided for educational information and study purposes only.

For more development background see the Science Lecture - Musculoskeletal Development and notes on Bone Development.

Musculoskeletal Links: Introduction | mesoderm | somitogenesis | limb | cartilage | bone | bone timeline | bone marrow | shoulder | pelvis | axial skeleton | skull | joint | skeletal muscle | muscle timeline | tendon | diaphragm | Lecture - Musculoskeletal | Lecture Movie | musculoskeletal abnormalities | limb abnormalities | developmental hip dysplasia | cartilage histology | bone histology | Skeletal Muscle Histology | Category:Musculoskeletal
Historic Embryology - Musculoskeletal  
1853 Bone | 1885 Sphenoid | 1902 - Pubo-femoral Region | Spinal Column and Back | Body Segmentation | Cranium | Body Wall, Ribs, and Sternum | Limbs | 1901 - Limbs | 1902 - Arm Development | 1906 Human Embryo Ossification | 1906 Lower limb Nerves and Muscle | 1907 - Muscular System | Skeleton and Limbs | 1908 Vertebra | 1908 Cervical Vertebra | 1909 Mandible | 1910 - Skeleton and Connective Tissues | Muscular System | Coelom and Diaphragm | 1913 Clavicle | 1920 Clavicle | 1921 - External body form | Connective tissues and skeletal | Muscular | Diaphragm | 1929 Rat Somite | 1932 Pelvis | 1940 Synovial Joints | 1943 Human Embryonic, Fetal and Circumnatal Skeleton | 1947 Joints | 1949 Cartilage and Bone | 1957 Chondrification Hands and Feet | 1968 Knee


  • Understand the general microanatomy of bone
  • Understand bone cell types (location, structure, function)
  • Understand the histology of compact and spongy bone
  • Understand the 2 forms of developmental bone formation

Practical Audio

Skeleton dance.gif

Files below are Quicktime audio files recorded Wednesday 12 - 2 PM class (Podcast MP3 versions to follow).

Part 1 - Adult Bone Structure‎ | Part 2 - Bone Structure‎ | Part 3 - Developing Endochondral Ossification‎ | Part 4‎ - Developing Intramembranous Ossification

MH - Please note "perichondrium" instead of "periosteum" error somewhere in the above audio. Open in a separate tab to play the audio in the background.


Histology and Cell Biology: An Introduction to Pathology, A.L. Kierszenbaum, 2002 - Connective Tissue, Chapter 4 pp118-129; Osteogenesis, Chapter 5 pp131-145


UNSW Virtual Slidebox Virtual Slidebox Phase 1

Virtual Slidebox of Histology Decalcified rib, bone marrow | Developing bone | Paget's disease of bone

Bone Structure



  • Diaphysis - shaft
  • Epiphysis - expanded ends
  • Metaphysis - connecting region (between diaphysis and epiphysial line)
  • Medullary Cavity - (marrow) cavity within the bone.

More? Terms

Compact bone

  • (dense) no spaces or hollows in the bone matrix visible to the eye.
  • forms the thick-walled tube of the shaft (or diaphysis) of long bones, which surrounds the marrow cavity (or medullary cavity). A thin layer of compact bone also covers the epiphyses of long bones.

Trabecular bone

  • (cancellous or spongy bone) consists of delicate bars (spicules) and sheets of bone, trabeculae
  • branch and intersect to form a sponge-like network
  • ends of long bones (or epiphyses) consist mainly of trabecular bone.


Connective tissue covering the surface of bone (except articular surfaces).



Connective tissue lining inner surface of bone.

Bone Growth

  • Appositional growth occurs at either the periosteum (outer surface), or the endosteum (inner surface).
  • Osteoblasts secrete osteoid, a pre-bone material composed mainly of type I collagen that becomes mineralized.
  • Early bone matrix deposited in development and during repair is woven rather than lamellar in appearance and structure.
  • In development, there are 2 distinct types of bone formation (intramembranous and endochondral)

Bone Cells


Mouse osteoblast 01.jpg

  • derive from osteogenic stem cells the osteoprogenitor cells that differentiate to form pre-osteoblast then osteoblasts maturing to an osteocyte
  • osteoprogenitor cells - "resting cell" line the inner and outer surfaces of bone


  • mature bone-forming cells embedded in lacunae within the bone matrix
  • osteoblasts and osteocytes - secrete organic matrix of bone (osteoid), converted into osteocytes when become embedded in matrix (which calcifies soon after deposition)


Mouse osteoclast 01.jpg Osteoclast.jpg Bone remodeling cycle.jpg

  • bone-resorbing multinucleated macrophage-like cells
  • origin- fusion of monocytes or macrophages, Blood macrophage precursor, Attach to bone matrix
  • seal a small segment of extracellular space (between plasma membrane and bone surface), HCl and lysosomes secreted into this space by osteoclasts dissolves calcium phosphate crystals (give bone rigidity and strength)
    • Resorptive bay - (Howship's lacuna) shallow bay lying directly under an osteoclast.
  • do not mistake for megakaryocytes, found in bone marrow not associated with bone matrix.
    • megakaryocytes are also multi-niucleated and form platelets

Bone Marrow

Hematopoietic and stromal cell differentiation
  • red marrow - mainly haematopoietic (myeloid) tissue, newborn has all red marrow
  • yellow marrow - mainly fat cells, found in diaphysis region of long bones
  • stromal cells - all other support cells not involved in haematopoiesis

Chondroblasts and Chondrocytes

  • immature and mature cartilage forming cells located at articular cartilage regions.
  • Interstitial growth - occurs mainly in immature cartilage. Chondroblasts in existing cartilage divide and form small groups of cells (isogenous groups) which produce matrix to become separated from each other by a thin partition of matrix.
  • Appositional growth - occurs also in mature cartilage. Mesenchymal cells surrounding the cartilage in the deep part of the perichondrium (or the chondrogenic layer) differentiate into chondroblasts.

Histology - Cartilage

Bone Matrix

The bone matrix has 2 major components.

  • Organic portion composed of mainly collagen Type 1 (about 95%) and amorphous ground substance.
  • Inorganic portion (50% dry weight of the matrix) composed of hydroxyapatite crystals, calcium, phosphorus, bicarbonate, nitrate, Mg, K, Na.
    • storage calcium and phosphate
    • regulate blood calcium levels

Haversian Systems

Bone structure cartoon
  • also called osteons
  • Volkmann's canals - interconnect Haversian systems


  • concentric - surrounding each Haversian System
  • interstitial - bony plates that fill in between the haversian systems.
  • circumferential - layers of bone that underlie the periosteum and endosteum


  • osteocytes extending cytoplasmic processes into canaliculi
  • Additional Histology images: low | medium | high

Endochondral ossification

Endochondral bone.jpg

Endochondral ossification slides: Developing bone | Bone, Developing (LS, Femur) Cat H&E

Blue Histology - endochondral | Dev Biology - endochondral ossification | endochondral ossification animation

Endochondral ossification.jpg Endochondral ossification 2.jpg

Ossification endochondral 1c.jpg Articular cartilage.jpg

Additional Histology Slides: developing Vertebra | Vertebra medium

Intramembranous Ossification

Intramembranous ossification slides: Head (Neonatal) Rat H& Van Gieson

Blue histology - intramembranous | intramembranous ossification animation

Ossification centre.jpg Intramembranous ossification centre.jpg

Human Fetal Head (12 week)

Fetal head medial.jpg Fetal head lateral.jpg


Fetal head section.jpg

Histology Stains

Alizarin Red

  • an anthraquinone derivative used to identify calcium in tissue sections
  • calcium forms an Alizarin Red S-calcium complex in a chelation process and the end product is also birefringent.
  • reaction can also identify magnesium, manganese, barium, strontium, and iron may interfere
    • these elements usually in too low concentration to interfere with the staining


  • acronym for hematoxylin and eosin stain
  • hematoxylin - basic dye which colors basophilic structures with blue-purple hue (nucleus, DNA, RNA)
  • eosin Y - acidic alcohol-based which colors eosinophilic structures bright pink (cytoplasm, extracellular matrix, protein)

H&Van Gieson

  • Van Gieson's Stain is a mixture of picric acid and acid fuchsin used for differential staining of collagen and other connective tissue.
    • Nuclei - stains brownish black to black
    • Collagen (fibrous connective tissue) - stains pink or deep red
    • Muscle, Cytoplasm, RBC and Fibrin - stains yellow

Links: Histology Stains

External Links

Other Textbooks



Axial skeleton
Appendicular skeleton
  • canaliculus - (plural, canaliculi) small channel in the bone matrix in which an osteocyte process lies and communicates with other osteocytes and the Haversian canal.
  • haematopoiesis (Greek, haima = "blood"; poiesis = "to make") the process of blood cell formation.
  • Haversian canal - the central canal of an osteon (Haversian system) in compact bone, within which blood vessels and nerves travel throughout the bone.
  • Haversian system - (osteon) the historic name for the functional unit of compact bone. Consists of a central canal (Haversian canal) surrounded by lamellar bone matrix within which osteocytes reside.
  • Howship's lacuna - (resorptive bay) the historic name for the shallow bay or cavity lying directly under an osteoclast. This is the site of bone matrix resorption.
  • lacuna - (Latin, lacuna = “ditch, gap” diminutive form of lacus = “lake”) lacunae is the plural, cavity in bone or cartilage for cell.
  • lamellar bone - the highly organized strong bone matrix deposited in concentric sheets with a low proportion of osteocytes. Many collagen fibers parallel to each other in the same layer.
  • osteon - (Haversian system) the functional unit of compact bone. Consists of a central canal (Haversian canal) surrounded by lamellar bone matrix within which osteocytes reside.
  • resorptive bay - (Howship's lacuna) the shallow bay or cavity lying directly under an osteoclast. This is the site of bone matrix resorption.
  • suture - in the skull a form of articulation where the contiguous margins of the bones are united by a thin layer of fibrous tissue.
  • woven bone - the first deposited weaker bone matrix with many osteocytes and a matrix disorganized structure. Replaced by lamellar bone. Seen in developing, healing and bone disease.

Glossary Links

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Cite this page: Hill, M.A. (2021, January 17) Embryology Bone Histology. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Bone_Histology

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© Dr Mark Hill 2021, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G