Lecture - Musculoskeletal Development

From Embryology


This lecture is an introduction to the process of musculoskeletal development (bone and skeletal muscle) (b. In the body, this is mainly about mesoderm differentiation beginning with an embryonic connective tissue structure, the mesenchyme.

In the head, this is a mixture of mesoderm and neural crest differentiation, from mesenchyme and ectomesenchyme respectively. The lecture will cover mainly cartilage and bone, as muscle will be covered in the limb lecture and in this week's laboratory.

The axial and the appendicular skeleton.

  • axial skeleton - 80 bones (skull, vertebrae, ribs, and sternum)
  • appendicular skeleton - 126 bones (shoulders, pelvis, and limbs)

Note that genes that control skeleton patterning and cell differentiation are different.

2018 Lecture - Print PDF

Axial skeleton.jpg

Axial skeleton

Appendicular skeleton.jpg

Appendicular skeleton

Lecture Objectives

  • Understanding of mesoderm and neural crest development.
  • Brief understanding of connective tissue development.
  • Understanding of cartilage, bone and muscle development.
  • Understanding of the two forms of bone development.
  • Brief understanding of molecular bone development.
  • Brief understanding of bone abnormalities.
Stage14 sem1c.jpg

Week 5 Embryo showing somites.

Mall1906 fig02.jpg

Week 9.5 Fetus showing bone formation.

Lecture Resources

Mesoderm 001 icon.jpg
 ‎‎Week 3 Mesoderm
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Notochord 01 icon.jpg
 ‎‎Week 3 Notochord
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Notochord 02 icon.jpg
 ‎‎Week 3 Notochord
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Vertebra 003 icon.jpg
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Somite 001 icon.jpg
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Somitogenesis 01 icon.jpg
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Mesoderm migration movie 1 icon.jpg
 ‎‎Mesoderm Move
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UNSW Embryology logo
Hill, M.A. (2020). UNSW Embryology (20th ed.) Retrieved June 21, 2024, from https://embryology.med.unsw.edu.au
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

Archive: 2017 | 2016 PDF | 2015 | 2014 PDF | 2014

Virtual Slide: Musculoskeletal Embryo Stage 22

ANAT2341 Lab 9

The Developing Human, 10th edn.jpg Moore, K.L., Persaud, T.V.N. & Torchia, M.G. (2015). The developing human: clinically oriented embryology (10th ed.). Philadelphia: Saunders.
Larsen's human embryology 5th ed.jpg Schoenwolf, G.C., Bleyl, S.B., Brauer, P.R., Francis-West, P.H. & Philippa H. (2015). Larsen's human embryology (5th ed.). New York; Edinburgh: Churchill Livingstone.
2016 Lecture Video Recording  
This 2016 lecture video recording is similar in content to the current 2017 online lecture.

<html5media height="600" width="800">File:2016Lecture-Musculoskeletal.mp4</html5media>

Click to play new window - 2016 Lecture Video (48 MB)

Patterning and differentiation of the somitic mesoderm

  • Week 3 to 4 - paraxial mesoderm forms somites (somitogenesis) along the rostro-caudal axis establishes the axial body plan
    • paraxial mesoderm remains unsegmented in the head
  • Hox gene clusters control rostro-caudal patterning of the axial musculoskeletal system
    • provide positional clues for the development of specific structures e.g. cervical, thoracic, lumbar and sacral vertebrae.

Proposed Hox protein classification.jpg

Somite Patterning

Each somite pair is initially patterned into the same verntro-dorsal components - sclerotome and dermomyotome
  • Ventral signal - from notochord (sonic hedgehog, SHH)
  • Dorsal signal - from overlying ectoderm (bone morphogenic protein, BMP)
Dermomyotome is then divided into a dorsal dermatome and a ventral myotome
  • Dermatome - dermis of the skin
  • Myotome - skeletal muscle
Somite cartoon3.png Somite cartoon4.png
Myotome is then divided into a dorsal epaxial and a ventral hypaxial muscle group
  • epaxial muscles - located behind the vertebral column.
  • hypaxial muscles - located in front of the vertebral column
    • ventral body wall
    • somites at the level of the limbs will also form limb muscles (covered in limb lecture)
Somite cartoon5.png

Neural Crest Derived Cells

(see Neural Crest and Head Lectures)

  • Neural crest-derived cells are essential to form the bones and cartilage of the face and neck
  • Also forms the cranial nerves and pigment cells, dorsal root ganglia and the sympathetic neurons.

Cartilage Development

Most of the skeleton is formed initially by cartilage that is then replaced by bone
    • described as a "cartilage template" for ossification (endochondral ossification)
    • except for joint surfaces - hyaline cartilage
  • Hyaline cartilage develops from mesenchymal cells, forming chondrification centres.
  • chondroblasts secrete ECM components of matrix, that separates them into lacunae.
Fetal cartilage 01.jpg

chondrification centre

Cartilage 3 stages:
  1. Signalling interactions between mesenchyme and an epithelial population
  2. Cell Condensation - mesenchymal dispersed cell population, gathers together to differentiate
  3. Overt Differentiation

Cartilage replacement

  • periosteal bud invades the cartilage and allows osteoprogenitor cells to enter the cartilage.
    • blood vessel growth and osteoprogenitor cells attracted by growth factors released from dying chondrocytes.
Cartilage Template  
Chicken- wing cartilage.jpg Mouse limb cartilage and bone E14.5L.jpg
Chicken limb - cartilage Mouse limb - cartilage and bone
Endochondral ossification.jpg

Endochondral ossification

Cartilage Growth

  • 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.

(review your Histology materials)

Hypertrophic Chondrocytes

  • secrete VEGF, promoting vascular invasion
  • hypertrophic calcified cartilage becomes resorbed, by recruited chondroclasts/osteoclasts via MMP9

Formation of Bone

Endochondral bone.jpg Ossification centre.jpg
Endochondral primary ossification centres Intramembranous ossification centres

  • Two main forms of bone formation: Endochondral and Intramembranous.
  • Ossification process continues postnatally through puberty until mid 20s.
Endochondral ossification 2.jpg

Endochondral initial primary and later secondary ossification centres (sites cartoon


Periosteum is the source of osteoprogeitors for later bone growth

Endochondral Ossification

Endochondral bone cartoon.jpg

Endochondral Ossification[1]

  • Majority of skeleton formed by this process (vertebra, limb long bones)
  • Osteoblasts derived from the bone collar replace cartilage matrix with a matrix rich in type I collagen leading to bone formation
  • Ossification centres (primary and secondary)
  • Early ossification occurs at ends of long bone

- Diagram of ossification in long bone University of Bristol - ossification

Endochondral bone development - Role of VEGF

Development of Vertebrae

Week 4 - somite sclerotome surrounds notochord.
  • notochord (and floorplate) induces sclerotome migration and vertebral body cartilages.
  • neural tube induces vertebral arches.
  • Scleretome has 2 components
    • Rostral (upper) loose and a caudal (lower) compact
  • Early vertebral arch joined dorsally by a ligament (See Week 8 (Stage 22) vertebral arch)
    • allows the arch to expand with spinal cord growth
Developing vertebra.jpg

Initial formation of vertebral body

Gray0101.jpg Gray0082.jpg
Limb Bone Timeline
Mouse limb bone development timeline.jpg

Mouse limb bone development timeline[2]

(Note - this is shown as a general example of developmental bone changes you do not need to know the details)

Links: Bone Development Timeline | primary and secondary sites | Mice lacking Cbfa1 (Runx2) don't form bone

Vertebral segmentation

  • shifted 1/2 somite caudally - by fusion rostral compact with caudal loose to form vertebra from 2 sclerotomes allows
  1. segmental spinal nerves to emerge between the vertebral bodies (at the same level as the intervertebral discs)
  2. somite-derived muscle masses to interconnect between the intervertebral joints.

Adult vertebral column

  • 33 total - 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 5 coccygeal
Vertebra 003 icon.jpg
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Axial Elements

Intervertebral Disc Ribs Sternum
Structure - annulus and nucleus pulposus
  • dense region of sclerotome.
  • notochord initially contributes to nucleus pulposus of each disc, contribution replaced and lost postnatally.

Ossification endochondral 1c.jpg

vertebra origin: body, arch, and costal process
  • dense region of sclerotome contributes costal processes (thoracic region).
    • chondrification commences day 45 and rib cage is cartilage by end of embryonic period.


  • mesenchyme from ventral body wall (manubrium, body, ziphoid).
  • sternal cartilage "bars" fuse with costal processes and developing clavicles by end of embryonic period.


Intramembranous Ossification

Fetal head medial.jpgFetal head lateral.jpg

Ossification centre.jpg
  • Specialized form of ossification from a mesenchymal membrane. (skull and clavicle)
  • Neural crest-derived mesenchymal cells proliferate - some cells differentiate to form blood vessels, others become osteoblasts and begin secreting collagen-proteoglycan matrix that can bind calcium salts.
  • Initial mesenchyme condensation is avascular.
  • Angiogenesis is then required for intramembranous osteogenesis (vessels provide circulating factors)

Links: - Intramembranous ossification


skull bones
12 week fetal head

The Skull is a unique skeletal structure in several ways: embryonic cellular origin (neural crest), form of ossification (intramembranous and endochondrial) and flexibility (fibrous sutures). Musculoskeletal Development - Skull Development

The bones enclosing the brain have large flexible fibrous joints (sutures) which allow firstly the head to compress and pass through the birth canal and secondly to postnatally expand for brain growth.

These sutures gradually fuse at different times postnatally, firstly the metopic suture in infancy and the others much later. Abnormal fusion (synostosis) of any of the sutures will lead to a number of different skull defects.


  • Osteoprogenitor cell - periosteum and endosteum
  • Osteoblast - Secrete bone matrix, differentiate into osteocytes
  • Osteocyte - Mature bone cell, Embedded in matrix, matrix calcifies soon after deposition
Blood and Stromal Stem Cells  
Hematopoietic and stromal cell differentiation.jpg


  • Formation of mature osteoclasts involved in bone resorption - the osteoblasts regulate this process through the production of RANKL (Receptor Activator for Nuclear Factor κ B Ligand) which is found on the cell surface of osteoblasts.
  • RANKL is a key player in rheumatoid arthritis.
  • Osteoclast origin - fusion of monocytes or macrophages, Blood macrophage precursor
  • Attach to bone matrix - very large cells containing 15-20 nucleii.
  • Lysosomes - released into space between ruffled border and bone matrix, enzymes break down collagen fibres, resorption bays or Howship's lacunae



(This lecture is about skeletal muscle)

  • Skeletal muscle - cells originate from the paraxial mesoderm. Myoblasts undergo frequent divisions and coalesce with the formation of a multinucleated, syncytial muscle fibre or myotube. The nuclei of the myotube are still located centrally in the muscle fibre. In the course of the synthesis of the myofilaments/myofibrils, the nuclei are gradually displaced to the periphery of the cell.
  • Cardiac muscle - cells originate from the prechordal splanchnic mesoderm.
  • Smooth muscle - cells originate from undifferentiated mesenchymal cells. These cells differentiate first into mitotically active cells, myoblasts, which contain a few myofilaments. Myoblasts give rise to the cells which will differentiate into mature smooth muscle cells.

Skeletal Muscle Stages

specified cells myoblasts primary myotube secondary myotube myofibre
somite myotome migration to muscle location and proliferation initial myoblast fusion later myoblast proliferation and fusion innervation and expression of contractile proteins
  1. Myoblast - individual progenitor cells (from myotome)
  2. Myotube - multinucleated, but undifferentiated contractile apparatus (sarcomere)
  3. Myofibre (myofiber, muscle cell) - multinucleated and differentiated sarcomeres
    1. primary myofibres - first-formed myofibres, act as a structural framework upon which myoblasts proliferate, fuse in linear sequence
    2. secondary myofibers - second later population of myofibres that form surrounding the primary fibres.
Mouse muscle development  
Mouse limb tissue development.jpg

Muscle Fibre Types

  • Motor neuron will regulate the contractile properties of all associated myofibres.
    • A group of individual myofibres within a muscle will be innervated by a single motor neuron.
  • myosin ATPase activity determines - type IIB, IIA, IIX, and I fibres
    • Type I fibres - appear red, due to the presence of myoglobin (main type in fetal life)
    • Type II fibres - appear white, due to the absence of myoglobin and their glycolytic nature.

Muscle fibre type table  
You do not need to know the detailed table below, it is provided for information purposes only.
Fibre Type Type I fibres Type II a fibres Type II x fibres Type II b fibres
Contraction time Slow Moderately Fast Fast Very fast
Size of motor neuron Small Medium Large Very large
Resistance to fatigue High Fairly high Intermediate Low
Activity Used for Aerobic Long-term anaerobic Short-term anaerobic Short-term anaerobic
Maximum duration of use Hours <30 minutes <5 minutes <1 minute
Power produced Low Medium High Very high
Mitochondrial density High High Medium Low
Capillary density High Intermediate Low Low
Oxidative capacity High High Intermediate Low
Glycolytic capacity Low High High High
Major storage fuel Triglycerides Creatine phosphate, glycogen Creatine phosphate, glycogen Creatine phosphate, glycogen
Myosin heavy chain,
human genes


This term is used to describe the region of the somite that contributes skeletal muscle to the embryo body. Each somite pair level gives rise to a group of skeletal muscles supplied by a specific segmental spinal nerve. The muscle arises from a specific somite and the spinal nerve arises from a specific level of the spinal cord (identified by vertebral column).

Spinal Nerve Table  
You do not need to know the detailed table below, it is provided for information purposes only.

Humans spinal nerves (from top to bottom) and muscular functions:

  • C3, 4 and 5 supply the diaphragm for breathing.
  • C5 supply shoulder muscles and muscles to bend our elbow.
  • C6 for bending the wrist back.
  • C7 for straightening the elbow.
  • C8 bends the fingers.
  • T1 spreads the fingers.
  • T1 –T12 supplies the chest wall and abdominal muscles.
  • L2 bends the hip.
  • L3 straightens the knee.
  • L4 pulls the foot up.
  • L5 wiggles the toes.
  • S1 pulls the foot down.
  • S3, 4 and 5 supply the bladder, bowel, sex organs, anal and other pelvic muscles.

Satellite Cells

Muscle stem cells located under the basal lamina around each skeletal muscle fibre.

  • They have a role in postnatal growth and also regeneration of muscle fibres.
Muscle satellite cell EM02.jpg


  • Musculoskeletal mass doubles by the end of puberty
  • regulated growth by - sex steroid hormones, growth hormone, insulin-like growth factors
  • accumulation of (peak) bone mass during puberty relates to future osteoporosis in old age


Additional abnormalities will be covered in the limb development lecture.

"Arthritis and musculoskeletal conditions affect more than 6 million Australians. In 2004-05, direct health expenditure on these conditions amounted to $4.0 billion or 7.5% of total allocated health expenditure in Australia." Health expenditure for arthritis and musculoskeletal conditions, 2004-05

Australian abnormalities graph allsystem.pngAustralian abnormalities pie skmus.png



  • Spina Bifida - neural tube failure to close, disrupts neural arch formation
  • Block vertebra - failure of vertebra separation, lumbar region, chrondrification abnormality
  • Klippel-Feil Syndrome - non-segmented cervical vertebra, more female
  • see also scoliosis


  • Accessory rib (extra rib cervical or lumbar uni- or bilateral), short-rib polydactyly syndrome (lethal, chondroplasia), pigeon chest (rib overgrowth), funnel chest (sternum depression and lower costal cartilages)

Osteogenesis Imperfecta

  • brittle-bone syndrome
  • abnormal collagen type I, fail to assemble triple helix, degrade imperfect collagen, leads to fragile bones


Scoliosis.jpgScoliosis xray.jpg

  • assymetric growth impairment of vertebral bodies
  • lateral deviation of spine (Lateral flexion, Forward flexion, Rotation of vertebral column on long axis)
  • compensated by movement of vertebral column above and below affected region (producing a primary and two secondary curves)
  • progresses rapidly in adolescence and becomes fixed once bone growth is completed.

Congenital Hip Dislocation

Congenital Hip Dislocation
  • Instability: 1:60 at birth; 1:240 at 1 wk: Dislocation untreated; 1:700
  • congenital instability of hip, later dislocates by muscle pulls or gravity
  • familial predisposition female predominance
  • Growth of femoral head, acetabulum and innominate bone are delayed until the femoral head fits firmly into the acetabulum


MH - Covered in next lecture and lab.

  • Congenital Myopathies
  • Muscular Dystrophy


  1. <pubmed>26893264</pubmed>
  2. <pubmed>22174793</pubmed>| PMC3235105 | PLoS One.

Online Textbooks


External Links

External Links Notice - The dynamic nature of the internet may mean that some of these listed links may no longer function. If the link no longer works search the web with the link text or name. Links to any external commercial sites are provided for information purposes only and should never be considered an endorsement. UNSW Embryology is provided as an educational resource with no clinical information or commercial affiliation.


Bone Terms  
Bone Development
  • canaliculi - (singular, canaliculus) small channel in the bone matrix in which an osteocyte process lies and communicates with other osteocytes and the Haversian canal. Allow osteocytes to communicate with each other and to exchange substances by diffusion.
  • cartilage - connective tissue from mesoderm in the embryo forms most of the initial skeleton which is replaced by bone. In adult, found on the surface of bone joints.
  • Cbfa1 - Core-Binding Factor 1 (Runx2) transcription factor protein key to the differentiation of bone OMIM: Cbfa1
  • centrum - the primordium of the vertebral body formed initially by the sclerotome.
  • circumferential lamellae - compact bone layers that underlie the periosteum and endosteum (endosteal lamellae). (see concentric and interstitial lamellae)
  • clavicle - (Latin, clavicle = little key) bone which locks shoulder to body.
  • Cobb angle - clinical term for measuring axial skeleton abnormality. Measures coronal plane deformity on antero-posterior plain radiographs in the classification of scoliosis. Named after the American orthopedic surgeon John Robert Cobb (1903 - 1967).
  • concentric lamellae - compact bone layers surrounding each osteon. (see interstitial and circumferential lamellae)
  • desmal ossification - (intramembranous ossification) the process of mesenchyme directly ossifying into bone without a pre-existing cartilage template. Vascularised regions of mesenchymal cells proliferate and differentiate into pre-osteoblasts and then osteoblasts, occurs in parts of the skull and the clavicle.
  • diaphysis - anatomical term that refers to the shaft of long bones.
  • endochondrial ossification - the process of replacement of the cartilagenous framework by osteoblasts with bone.
  • endosteum - inner layer of cells lining the medullary cavity of long bones and is highly vascularised. A similar cellular region and fibrous layer lies on the outside of the bone, the periosteum.
  • epiphysis - anatomical term that refers to the expanded ends of long bones.
  • extracellular matrix - material secreted by and surrounding cells. Consists if fibers and ground substance.
  • fibroblast growth factors - (FGF) a family of at least 10 secreted proteins that bind membrane tyrosine kinase receptors. A patterning switch with many different roles in different tissues. (FGF8 = androgen-induced growth factor (AIGF)
  • fibroblast growth factor receptor - receptors comprise a family of at least 4 related but individually distinct tyrosine kinase receptors (FGFR1- 4). They have a similar protein structure, with 3 immunoglobulin-like domains in the extracellular region, a single membrane spanning segment, and a cytoplasmic tyrosine kinase domain.
  • heterotopic ossification - (HO) a disorder of extra-skeletal bone formation that occurs as a complication of trauma or in rare genetic disorders. PMID28455214
  • haematopoiesis (Greek, haima = "blood"; poiesis = "to make") the process of blood cell formation. In the adult, this occurs only in the bone marrow. In the embryo this occurs in other locations (yolk sac, liver, spleen, thymus) until bone develops.
  • 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. Named after Clopton Havers (1650-1702) an English physician and anatomist. PMID12999959
  • 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. Named after John Howship (1781–1841) a British anatomist who identified this region in 1820.
  • hyoid bone - part of the axial skeleton, is a U-shape bone in the neck that anchors the tongue and is associated with swallowing.
  • interstitial lamellae - compact bone layers that fill in between each osteon, interstitial lamellae, and do appear part of any Haversian system. (see concentric and circumferential lamellae)
  • intramembranous ossification - (desmal ossification) the process of mesenchyme directly ossifying into bone without a pre-existing cartilage template. Vascularised regions of mesenchymal cells proliferate and differentiate into pre-osteoblasts and then osteoblasts, occurs in parts of the skull and the clavicle.
  • 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. Replaces woven bone.
  • medullary cavity - (bone marrow) refers to the cavity within the bone, that is lined with cells (endosteum) and filled with bone marrow. in the adult, this can also be identified as either red or yellow marrow.
  • mesenchymal progenitor cells - (MPCs) cells able to differentiate in various types of connective tissue, including cartilage, bone and adipose tissue.
  • metaphysis - anatomical term that connecting region, that lies between the diaphysis and epiphysial line.
  • Moiré topography - clinical term for measuring axial skeleton abnormality. Measures spinal deviations using Moiré topography, a biosteriometric method producing a three-dimensional image of the shape of the trunk.
  • osteoblast - The mesenchymal cells that differentiate to form the cellular component of bone and produce bone matrix. Mature osteoblasts are called osteocytes. (More? bone)
  • osteoclast - Cells that remove bone (bone resorption) by enzymatically eroding the bone matrix. These cells are monocyte-macrophage in origin and fuse to form a multinucleated osteoclast. These cells allow continuous bone remodelling and are also involved in calcium and phosphate metabolism. The erosion cavity that the cells lie iwithin and form is called Howship's lacuna. (More? bone)
  • osteocyte - The mature bone-forming cell, which form the cellular component of bone and produce bone matrix. Differentiate from osteoblasts, mesenchymal cells that differentiate to form bone. (More? bone)
  • 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.
  • pedicle - (Latin, pediculus = small foot) part of the vertebral arch forming the segment between the transverse process and the vertebral body.
  • periosteum - the cellular region and fibrous layer lying on the outside of the bone.
  • primary centre of ossification - the first area where bone growth occurs between the periosteum and cartilage.
  • resorptive bay - (Howship's lacuna) the shallow bay or cavity lying directly under an osteoclast. This is the site of bone matrix resorption.
  • sclerotome - ventromedial half of each somite that forms the vertebral body and intervertebral disc.
  • Scoliometry - clinical term for measuring axial skeleton abnormality using a Pedi-Scoliometer (Pedihealth Oy, Oulu, Finland) to measure spine deviation.
  • Sharpey’s fibres - (SF) “perforating fibres” provide anchorage for the periosteum and in tooth anchorage.
  • suture - in the skull a form of articulation where the contiguous margins of the bones are united by a thin layer of fibrous tissue.
  • trabecular bone - lamellar bone not forming Haversian systems.
  • 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.
Other Terms Lists  
Terms Lists: ART | Birth | Bone | Cardiovascular | Cell Division | Endocrine | Gastrointestinal | Genital | Genetic | Head | Hearing | Heart | Immune | Integumentary | Neonatal | Neural | Oocyte | Palate | Placenta | Radiation | Renal | Respiratory | Spermatozoa | Statistics | Tooth | Ultrasound | Vision | Historic | Drugs | Glossary


 2018 ANAT2341 - Timetable | Course Outline | Moodle | Tutorial 1 | Tutorial 2 | Tutorial 3

Labs: 1 Preimplantation and Implantation | 2 Reproductive Technology Revolution | 3 Group Projects | 4 GM manipulation mouse embryos | 5 Early chicken eggs | 6 Female reproductive tract | 7 Skin regeneration | 8 Vertebral development | 9 Organogenesis Lab | 10 Cardiac development | 11 Group projects | 12 Stem Cell Journal Club

Lectures: 1 Introduction | 2 Fertilization | 3 Week 1/2 | 4 Week 3 | 5 Ectoderm | 6 Placenta | 7 Mesoderm | 8 Endoderm | 9 Research Technology | 10 Cardiovascular | 11 Respiratory | 12 Neural crest | 13 Head | 14 Musculoskeletal | 15 Limb | 16 Renal | 17 Genital | 18 Endocrine | 19 Sensory | 20 Fetal | 21 Integumentary | 22 Birth | 23 Stem cells | 24 Revision

 Student Projects: Group Projects Information Project 1 | Project 3 | Project 4 | Project 5 | 2018 Test Student | Copyright