Musculoskeletal System - Appendicular Skeleton Development

From Embryology


Human embryonic limb development (week 8)
Appendicular skeleton
Limb bud geometry and patterning[1]

The mesoderm forms nearly all the connective tissues of the musculoskeletal system. Each tissue (cartilage, bone, and muscle) goes through many different mechanisms of differentiation.

The musculoskeletal system consists of skeletal muscle, bone, and cartilage and is mainly mesoderm in origin with some neural crest contribution.

The intraembryonic mesoderm can be broken into paraxial, intermediate and lateral mesoderm relative to its midline position. During the 3rd week the paraxial mesoderm forms into "balls" of mesoderm paired either side of the neural groove, called somites.

Somites appear bilaterally as pairs at the same time and form earliest at the cranial (rostral,brain) end of the neural groove and add sequentially at the caudal end. This addition occurs so regularly that embryos are staged according to the number of somites that are present. Different regions of the somite differentiate into dermomyotome (dermal and muscle component) and sclerotome (forms vertebral column).

Bone is formed through a lengthy process involving ossification of a cartilage formed from mesenchyme. Two main forms of ossification occur in different bones, intramembranous (eg skull) and endochondrial (eg limb long bones) ossification. Ossification continues postnatally, through puberty until mid 20s. Early ossification occurs at the ends of long bones.

Musculoskeletal and limb abnormalities are one of the largest groups of congenital abnormalities.

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

Factor Links: AMH | hCG | BMP | sonic hedgehog | bHLH | HOX | FGF | FOX | Hippo | LIM | Nanog | NGF | Nodal | Notch | PAX | retinoic acid | SIX | Slit2/Robo1 | SOX | TBX | TGF-beta | VEGF | WNT | Category:Molecular

Some Recent Findings

Human embryo femur CS18 to CS23
Human embryo femur CS18 to CS23[2]
  • Morphogenesis of the femur at different stages of normal human development[2] "The present study aimed to better characterize the morphogenesis of the femur from the embryonic to the early fetal periods. Sixty-two human fetal specimens (crown-rump length [CRL] range: 11.4-185 mm) from the Kyoto Collection were used for this study. The morphogenesis and internal differentiation process of the femur were analyzed in 3D using phase-contrast X-ray computed tomography and magnetic resonance imaging. The cartilaginous femur was first observed at Carnegie stage 18. Major anatomical landmarks were formed prior to the initiation of ossification at the center of the diaphysis (CRL, 40 mm), as described by Bardeen. The region with very high signal intensity (phase 5 according to Streeter's classification; i.e., area described as cartilage disintegration) emerged at the center of the diaphysis, which split the region with slightly low signal intensity (phase 4; i.e., cartilage cells of maximum size) in fetuses with a CRL of 40.0 mm. The phase 4 and phase 5 regions became confined to the metaphysis, which might become the epiphyseal cartilage plate. Femur length and ossified shaft length (OSL) showed a strong positive correlation with CRL. The OSL-to-femur length ratio rapidly increased in fetuses with CRL between 40 and 75 mm, which became moderately increased in fetuses with a CRL of ≥75 mm. Cartilage canal invasion occurred earlier at the proximal epiphysis (CRL, 62 mm) than at the distal epiphysis (CRL, 75 mm). Morphometry and Procrustes analysis indicated that changes in the femur shape after ossification were limited, which were mainly detected at the time of initial ossification and shortly after that. In contrast, femoral neck anteversion and torsion of the femoral head continuously changed during the fetal period. Our data could aid in understanding the morphogenesis of the femur and in differentiating normal and abnormal development during the early fetal period."
  • Transient downregulation of Bmp signalling induces extra limbs in vertebrates[3] "Bone morphogenetic protein (Bmp) signalling has been implicated in setting up dorsoventral patterning of the vertebrate limb and in its outgrowth. Here, we present evidence that Bmp signalling or, more precisely, its inhibition also plays a role in limb and fin bud initiation. Temporary inhibition of Bmp signalling either by overexpression of noggin or using a synthetic Bmp inhibitor is sufficient to induce extra limbs in the Xenopus tadpole or exogenous fins in the Danio rerio embryo, respectively. We further show that Bmp signalling acts in parallel with retinoic acid signalling, possibly by inhibiting the known limb-inducing gene wnt2ba."
  • Global gene expression analysis of murine limb development[4] "Here we describe the global gene expression dynamics during early murine limb development, when cartilage, tendons, muscle, joints, vasculature and nerves are specified and the musculoskeletal system of limbs is established. We used whole-genome microarrays to identify genes with differential expression at 5 stages of limb development (E9.5 to 13.5), during fore- and hind-limb patterning."
More recent papers  
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Search term: Appendicular Skeleton Development | Limb Skeleton Development

Older papers  
These papers originally appeared in the Some Recent Findings table, but as that list grew in length have now been shuffled down to this collapsible table.

See also the Discussion Page for other references listed by year and References on this current page.

  • Spatially Controlled Cell Proliferation in Limb Bud Morphogenesis[5] "Our data run contrary to the proliferation gradient hypothesis, indicating instead that oriented cell behaviours are important for driving elongation."
  • Distinct roles of Hand2 in initiating polarity and posterior Shh expression during the onset of mouse limb bud development[6] "One such event is antero-posterior (AP) polarization of early limb buds and activation of morphogenetic Sonic Hedgehog (SHH) signaling in the posterior mesenchyme, which in turn promotes outgrowth and specifies the pentadactylous autopod. Inactivation of the Hand2 transcriptional regulator from the onset of mouse forelimb bud development disrupts establishment of posterior identity and Shh expression, which results in a skeletal phenotype identical to Shh deficient limb buds. ... Our study uncovers essential components of the transcriptional machinery and key interactions that set-up limb bud asymmetry upstream of establishing the SHH signaling limb bud organizer."
  • The apical ectodermal ridge (AER) can be re-induced by wounding[7] "First, we assessed the sequence of events following limb amputation in chick embryos and compared the features of limb development and regeneration in amphibians and chicks. Based on our findings, we attempted to re-induce the AER. When wnt-2b/fgf-10-expressing cells were inserted concurrently with wounding, successful re-induction of the AER occurred."


The Developing Human, 9th edn.jpg Keith L. Moore, T.V.N. Persaud, Mark G. Torchia. (2011). The Developing Human: clinically oriented embryology (9th ed.). Philadelphia: Saunders.
Larsen's human embryology 4th edn.jpg Schoenwolf, G.C., Bleyl, S.B., Brauer, P.R. and Francis-West, P.H. (2009). Larsen’s Human Embryology (4th ed.). New York; Edinburgh: Churchill Livingstone Chapter 18 - Development of the Limbs (chapter links only work with a UNSW connection).
  • Essentials of Human Embryology Larson Chapter 11 p207-228


Mouse limb (E14.5)
  • Identify the components of a somite and the adult derivatives of each component.
  • Give examples of sites of (a) endochondral and (b) intramembranous ossification and to compare these two processes.
  • Identify the general times (a) of formation of primary and (b) of formation of secondary ossification centres, and (c) of fusion of such centres with each other.
  • Briefly summarise the development of the limbs.
  • Describe the developmental abnormalities responsible for the following malformations: selected growth plate disorders; congenital dislocation of the hip; scoliosis; arthrogryposis; and limb reduction deformities.

Development Overview

Below is a very brief overview using simple figures of 3 aspects of early musculoskeletal development. More detailed overviews are shown on other notes pages Mesoderm and Somite, Vertebral Column, Limb in combination with serial sections and Carnegie images.

Mesoderm Development

Mesoderm cartoon 01.jpg Cells migrate through the primitive streak to form mesodermal layer. Extraembryonic mesoderm lies adjacent to the trilaminar embryo totally enclosing the amnion, yolk sac and forming the connecting stalk.
Mesoderm cartoon 02.jpg Paraxial mesoderm accumulates under the neural plate with thinner mesoderm laterally. This forms 2 thickened streaks running the length of the embryonic disc along the rostrocaudal axis. In humans, during the 3rd week, this mesoderm begins to segment. The neural plate folds to form a neural groove and folds.
Mesoderm cartoon 03.jpg Segmentation of the paraxial mesoderm into somites continues caudally at 1 somite/90minutes and a cavity (intraembryonic coelom) forms in the lateral plate mesoderm separating somatic and splanchnic mesoderm.

Note intraembryonic coelomic cavity communicates with extraembryonic coelom through portals (holes) initially on lateral margin of embryonic disc.

Mesoderm cartoon 04.jpg Somites continue to form. The neural groove fuses dorsally to form a tube at the level of the 4th somite and "zips up cranially and caudally and the neural crest migrates into the mesoderm.

Somite Development

Mesoderm cartoon 05.jpg Mesoderm beside the notochord (axial mesoderm, blue) thickens, forming the paraxial mesoderm as a pair of strips along the rostro-caudal axis.
Mesoderm cartoon 06.jpg Paraxial mesoderm towards the rostral end, begins to segment forming the first somite. Somites are then sequentially added caudally. The somitocoel, is a cavity forming in early somites, which is lost as the somite matures.
Mesoderm cartoon 07.jpg Cells in the somite differentiate medially to form the sclerotome (forms vertebral column) and dorsolaterally to form the dermomyotome.
Mesoderm cartoon 08.jpg The dermomyotome then forms the dermotome (forms dermis) and myotome (forms muscle).

Neural crest cells migrate beside and through somite.

Mesoderm cartoon 09.jpg The myotome differentiates to form 2 components dorsally the epimere and ventrally the hypomere, which in turn form epaxial and hypaxial muscles respectively. The bulk of the trunk and limb muscle coming from the Hypaxial mesoderm. Different structures will be contributed depending upon the somite level.

Limb skeletal muscle arises from the hypomere region of the myotomes adjacent to the developing upper (C5-C8) and lower (L3-L5) limb buds.

Limb Axis Formation

Limb bud geometry and patterning[1]

Four Concepts - much of the work has been carried out using the chicken and more recently the mouse model of development.

  1. Limb Initiation
  2. Proximodistal Axis
  3. Dorsoventral Axis
  4. Anteroposterior Axis

Mouse limb Patterning Images

Mouse Limb Images: Tbx3 and Tbx2 forelimb E10 | Alx3 and Gli3 forelimb E10 | Fgf and Hox forelimb E10.5 | Bmp4 forelimb E11.5 | Bmp4 hindlimb E11.5 | Shh forelimb E11.5 | Fgf8 hindlimb E11.5 | Sox9 forelimb E12.5 | Msx2 forelimb E12.5 | Shh hindlimb E12.5
Links: Fgf | Hox | Shh | Sox | Limb Development | Mouse Development

Limb Initiation

  • Fibroblast growth factor (FGF) coated beads can induce additional limb
  • FGF10 , FGF8 (lateral plate intermediate mesoderm) prior to bud formation
  • FGF8 (limb ectoderm) FGFR2
  • FGF can respecify Hox gene expression (Hox9- limb position)
  • Hox could then activate FGF expression

Note that during the embryonic period there is a rostrocaudal (anterior posterior) timing difference between the upper and lower limb development

  • this means that developmental changes in the upper limb can precede similar changes in the lower limb (2-5 day difference in timing)

Limb Identity

Forelimb and hindlimb (mouse) identity appears to be regulated by T-box (Tbx) genes, which are a family of transcription factors.

  • hindlimb Tbx4 is expressed.
  • forelimb Tbx5 is expressed.
  • Tbx2 and Tbx3 are expressed in both limbs.

Related Research - PMID: 12490567 | Development 2003 Figures | Scanning electron micrographs of E9 Limb bud wild-type and Tbx5del/del A model for early stages of limb bud growth | PMID: 12736217 | Development 2003 Figures

Limb patterning factors 09.jpg

Tbx3 and Tbx2 expression in E9.75 to 10.5 wild-type mouse embryonic forelimb.[6]

Body Axes

  • Anteroposterior - (Rostrocaudal, Craniocaudal, Cephalocaudal) from the head end to opposite end of body or tail.
  • Dorsoventral - from the spinal column (back) to belly (front).
  • Proximodistal - from the tip of an appendage (distal) to where it joins the body (proximal).

Proximodistal Axis

Limb proximodistal developmental regions
Mouse limb (E14.5)
  • Apical Ectodermal Ridge (AER) formed by Wnt7a
  • then AER secretes FGF2, 4, 8
  • stimulates proliferation and outgrowth

The developing limb can be described along the proximodistal axis as having three main regions:

  1. Stylopod - the proximal region the limb, the skeletal component of the upper limb (forelimb) is the humerus, and for the lower limb (hindlimb) is the femur.
  2. Zeugopod - the mid-section of the limb , the skeletal components of the upper limb (forelimb) are the radius and ulna, and for the lower limb (hindlimb) are the tibia and fibula.
  3. Autopod - the distal region the limb, the musculoskeletal component of the upper limb (forelimb) is the hands, and for the lower limb (hindlimb) is the foot.

Dorsoventral Axis

  • Somites - provides dorsal signal to mesenchyme which dorsalizes ectoderm
  • Ectoderm - then in turn signals back (Wnt7a) to mesenchyme to pattern limb


  • name was derived from 'wingless' and 'int’
  • Wnt gene first defined as a protooncogene, int1
  • Humans have at least 4 Wnt genes
  • Wnt7a gene is at 3p25 encoding a 349aa secreted glycoprotein
  • patterning switch with different roles in different tissues
  • mechanism of Wnt and receptor distribution still being determined (free diffusion, restricted diffusion and active transport)

One WNT receptor is Frizzled (FZD)

  • Frizzled gene family encodes a 7 transmembrane receptor

Fibroblast growth factors (FGF)

  • Family of at least 17 secreted proteins
  • bind membrane tyrosine kinase receptors
  • Patterning switch with many different roles in different tissues
  • FGF8 = androgen-induced growth factor, AIGF

FGF receptors

  • comprise a family of at least 4 related but individually distinct tyrosine kinase receptors (FGFR1- 4) similar protein structure
    • 3 immunoglobulin-like domains in extracellular region
    • single membrane spanning segment
    • cytoplasmic tyrosine kinase domain

Anteroposterior Axis

Shh expression in ZPA mouse forelimb (E11.5)[8]
  • Zone of polarizing activity (ZPA)
  • a mesenchymal posterior region of limb
  • secretes sonic hedgehog (SHH)
    • note digit 1 (thumb/big toe) is the only digit that forms independent of SHH activity.
  • apical ectodermal ridge (AER), which has a role in patterning the structures that form within the limb
  • majority of cell division (mitosis) occurs just deep to AER in a region known as the progress zone
  • A second region at the base of the limbbud beside the body, the zone of polarizing activity (ZPA) has a similar patterning role to the AER, but in determining another axis of the limb

Week 5

Stage13 bf2.jpg Stage14 somites limbbuds.png Stage15 bf1.jpg
Carnegie stage 13 Carnegie stage 14 Carnegie stage 15
Stage14 sem2l.jpg

Links: Week 5 | Carnegie stage 13 | Carnegie stage 14 | Carnegie stage 15

Week 6


Digital rays become visible on the upper limb.

Links: Week 6 | Carnegie stage 16 | Carnegie stage 17

Week 7

Stage18 bf1.jpg Stage18 bf1.jpg
Carnegie stage 18 Carnegie stage 19

Digital rays become visible on the lower limb.

Links: Week 7 | Carnegie stage 18 | Carnegie stage 19

Week 8

Stage20-23 limbs.jpg

Links: Week 8 | Carnegie stage 20 | Carnegie stage 21 | Carnegie stage 22 | Carnegie stage 23

Limb Rotation

Stage19- limb rotation.jpg

Human Embryo (stage 19) showing direction of limb rotation.

Fetal Growth

<html5media height="320" width="285">File:fetal growth.mp4</html5media> Embryonic period - the external appearance of both the upper and lower limb has been formed.

Fetal period - the limbs continue to grow significantly in length (elongate).

Play the associated animation to observe the relative change in limb dimensions.

Links: Fetal Development

Limb Bone

Carnegie stages for limb elements appearance
Skeletal Element Condensed
Cartilage Bone
Mouse limb cartilage and bone.jpg Humerus 16 1617 2122
Radius 16 17 2123
Ulna 16 1718 1723
Hand 17 1721 In fetus1and after birth
Femur 17 1718 2223
Patella 20 21 After birth
Tibia 17 1723 2223
Fibula 17 1718 In fetus
Foot 1718 1823 or later in fetus and after birth
   1 Intramembranous ossification at the tips of the distal phalanges of the hand may be in Stage 23.
Reference - O'Rahilly R. Gray DI. and Gardner E. Chondrification in the hands and feet of staged human embryos. (1957) Carnegie Instn. Wash. Publ. 611, Contrib. Embryol., 36:
Limb sox9 and Wnt6 expression[9]
Chicken- limb bud chondrogenesis

Bone formation within the limb occurs by endochondral ossification of a pre-existing cartilage template. Ossification then replaces the existing cartilage except in the regions of articulation, where cartilage remains on the surface of the bone within the joint. Therefore bone development in the limb is initially about cartilage development or chondrogenesis.

In addition, there are two quite separate aspects to this development.

  1. Pattern - where the specific regions will commence to form cartilage, which will be different for each cartilage element.
  2. Chondrogenesis - the differentiation of mesoderm to form cartilage, which will be essentially the same program for all cartilage templates.

A recent study has identified that the overlying limb surface ectoderm potentially inhibits limb early chondrogenesis through Wnt6 signaling.[9]

Links: cartilage | bone

Shoulder and Pelvis

Hip bone

The skeletal shoulder consists of: the clavicle (collarbone), the scapula (shoulder blade), and the humerus. Development of his region occurs through both forms of ossification processes.

Congenital dislocation hip.jpg

The skeletal pelvis consists of: the sacrum and coccyx (axial skeleton), and pelvic girdle formed by a pair of hip bones (appendicular skeleton). Before puberty, he pelvic girdle also consists of three unfused bones: the ilium, ischium, and pubis. In chicken, the entire pelvic girdle originates from the somatopleure mesoderm (somite levels 26 to 35) and the ilium, but not of the pubis and ischium, depends on somitic and ectodermal signals.[10]

Links: Musculoskeletal System - Shoulder Development | Musculoskeletal System - Pelvis Development

Wing as Limb Model

Chicken - wing cartilage

  • chicken wing easy to manipulate
    • removal, addition and rotation of limb regions
    • grafting additional AER, ZPA
    • implanting growth factor secreting structures

Mouse Limb Model

Mouse limb skeleton cartoon.jpg Mouse limb tissue development.jpg
Mouse limb skeleton cartoon[11]

Fore-limb and hind-limb buds for stages E9.5 to E13.5. Hindlimbs are morphologically delayed by about half a day.

  • Light blue - indicate mesenchymal condensations.
  • Thick black lines - indicate cartilage as determined by alcian blue staining.
Change in cell types and tissue formation as a function of mouse developmental stage.[11]


Mouse forelimb gene expression.jpg


Mouse hindlimb gene expression.jpg

Links: Mouse Development

Bat Limb Model

Bat limb 02.jpg

Bat limb 01.jpg

Images of the bat embryo Miniopterus schreibersii fuliginosus at embryonic Stages 13-17.[12]

(aer - apical ectodermal ridge; chp - chiropatagium; eb - elbow; kn - knee)

Links: Bat Limb Development | Bat Development


Fibroblast Growth Factors

  • Fgf8 - morphogen gradient forms by a source-sink mechanism with freely diffusing molecules.[13]

T-box Transcription Factors


The HAND2 gene encodes a basic helix-loop-helix (bHLH).

Links: Fibroblast Growth Factor | Sonic hedgehog | Wnt | Hand2 | OMIM


  1. 1.0 1.1 Kicheva A & Briscoe J. (2010). Limbs made to measure. PLoS Biol. , 8, e1000421. PMID: 20644713 DOI.
  2. 2.0 2.1 Suzuki Y, Matsubayashi J, Ji X, Yamada S, Yoneyama A, Imai H, Matsuda T, Aoyama T & Takakuwa T. (2019). Morphogenesis of the femur at different stages of normal human development. PLoS ONE , 14, e0221569. PMID: 31442281 DOI.
  3. Christen B, Rodrigues AM, Monasterio MB, Roig CF & Izpisua Belmonte JC. (2012). Transient downregulation of Bmp signalling induces extra limbs in vertebrates. Development , 139, 2557-65. PMID: 22675213 DOI.
  4. <pubmed>22174793</pubmed>
  5. Boehm B, Westerberg H, Lesnicar-Pucko G, Raja S, Rautschka M, Cotterell J, Swoger J & Sharpe J. (2010). The role of spatially controlled cell proliferation in limb bud morphogenesis. PLoS Biol. , 8, e1000420. PMID: 20644711 DOI.
  6. 6.0 6.1 <pubmed>20386744</pubmed> Cite error: Invalid <ref> tag; name 'PMID20386744' defined multiple times with different content
  7. Satoh A, Makanae A & Wada N. (2010). The apical ectodermal ridge (AER) can be re-induced by wounding, wnt-2b, and fgf-10 in the chicken limb bud. Dev. Biol. , 342, 157-68. PMID: 20347761 DOI.
  8. Bandyopadhyay A, Tsuji K, Cox K, Harfe BD, Rosen V & Tabin CJ. (2006). Genetic analysis of the roles of BMP2, BMP4, and BMP7 in limb patterning and skeletogenesis. PLoS Genet. , 2, e216. PMID: 17194222 DOI.
  9. 9.0 9.1 Geetha-Loganathan P, Nimmagadda S, Christ B, Huang R & Scaal M. (2010). Ectodermal Wnt6 is an early negative regulator of limb chondrogenesis in the chicken embryo. BMC Dev. Biol. , 10, 32. PMID: 20334703 DOI.
  10. <pubmed>18087724</pubmed>
  11. 11.0 11.1 Taher L, Collette NM, Murugesh D, Maxwell E, Ovcharenko I & Loots GG. (2011). Global gene expression analysis of murine limb development. PLoS ONE , 6, e28358. PMID: 22174793 DOI. Cite error: Invalid <ref> tag; name 'PMID22174793' defined multiple times with different content
  12. Wang Z, Han N, Racey PA, Ru B & He G. (2010). A comparative study of prenatal development in Miniopterus schreibersii fuliginosus, Hipposideros armiger and H. pratti. BMC Dev. Biol. , 10, 10. PMID: 20092640 DOI.
  13. <pubmed>19741606</pubmed>


Wagner GP & Vargas AO. (2008). On the nature of thumbs. Genome Biol. , 9, 213. PMID: 18341703 DOI.

Hill RE. (2007). How to make a zone of polarizing activity: insights into limb development via the abnormality preaxial polydactyly. Dev. Growth Differ. , 49, 439-48. PMID: 17661738 DOI.


Satoh A, Makanae A & Wada N. (2010). The apical ectodermal ridge (AER) can be re-induced by wounding, wnt-2b, and fgf-10 in the chicken limb bud. Dev. Biol. , 342, 157-68. PMID: 20347761 DOI.

Galli A, Robay D, Osterwalder M, Bao X, Bénazet JD, Tariq M, Paro R, Mackem S & Zeller R. (2010). Distinct roles of Hand2 in initiating polarity and posterior Shh expression during the onset of mouse limb bud development. PLoS Genet. , 6, e1000901. PMID: 20386744 DOI.

Stefanov EK, Ferrage JM, Parchim NF, Lee CE, Reginelli AD, Taché M & Anderson RA. (2009). Modification of the zone of polarizing activity signal by trypsin. Dev. Growth Differ. , 51, 123-33. PMID: 19207183 DOI.

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Additional Images

Historic Images

Limb Images: 274-278 Spinal Column and Lower Limb | 279-284 Lower Limb | 285-288 Knee | 289 Os Coxae | 290 Femur | 291 Tibia | 292 Fibula | 293 Foot | 294 | 295 | 296 | 297 | 298-299 | 300 Forearm and Hand | 301 Upper Limb Joints | 302 Clavicle | Upper Limb Ossification 1 | Upper Limb Ossification 2 | Bone Development Timeline

Skeleton and Connective Tissues: Connective Tissue Histogenesis | Skeletal Morphogenesis | Chorda Dorsalis | Vertebral Column and Thorax | Limb Skeleton | Skull Hyoid Bone Larynx

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Cite this page: Hill, M.A. (2024, March 4) Embryology Musculoskeletal System - Appendicular Skeleton Development. Retrieved from

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