The timing and sequence of events in the development of the limbs in the human embryo

OʼRahilly, Ronan; Gardner, Ernest

doi:10.1007/bf00315559

Cited by 184 publications

(106 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In the 6th week, the primordium of the femoral head is completely composed of cartilage and the joint cavity has already been formed, which was also confirmed by O'Rahilly and Gardner (1975). In this stage, the cartilaginous primordium has all the characteristics of an immature cartilaginous tissue.…”

Section: Discussionsupporting

confidence: 57%

“…Light microscopic studies of early ontogenetic development of articular structures in man have been made by a large number of authors (Gray et al, 1957;Gardner and O'Rahilly 1968;Cihak 1972;O'Rahilly and Gardner 1975;Glenister 1976;Levitt and Dorfman 1974, inter alia). It follows from these works that articular surfaces as well as other joint components come into existence in the period between the 6th and lOth week after fertilization and that the joint cavity appears in the 8th week (Gardner and O'Rahilly 1968).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Submicroscopic Structure of Human Articular Cartilage in the Period of 19 to 38 Weeks after Fertilization

Horký¹

1991

Acta Vet. Brno

View full text Add to dashboard Cite

Horky D.: Submicroscopic Structure of Human Articular Cartilage in the Period of 19 to 38 Weeks After Fertilization. Acta vet. Bmo, 60, 1991: 111-126.Articular cartilage of 15 and 19 foetuses of both sexes aged between 19 to 38 weeks after fertilization was studied by transmission electron microscopy and scanning electron microscopy, respectively. The specirilens, obtained from indicated abortions and spontaneous miscarriages, were processed by routine methods.In the course of the development of articular cartilage, certain periods can be distinguished which clearly reflect the changes in the submicroscopic structure of its individual components and in the forming of its surface. In the first ninety days, such a period occurs between the 6th and 11th week after fertilization. Later, such periods occur at the age of 19 to 20 weeks and 27 to 37 weeks after fertilization. The two latter periods were the subject matter of our investigations.Besides other changes, the period between the 19th and 20th week marks the appearance of intracytoplasmic filaments in the cytoplasm of chondroblasts in the surface and middle layers as an important differentiation sign, and in the 27th week the chondral membrane first appears on the surface of the cartilage. In the period between the 27th and 36th week of development, differentiation changes in chondroblasts continue and, as a result, the cells attain characteristics of chondrocytes of adult cartilage. The fibrous component of intercellular substance becomes more abundant, so that the differentiation between the pericellular and intercellular matrices, particularly in the middle and deep layers, is quite clear.Up to the 19th to 20th week of development, cartilaginous surface is very uneven. Covered with a surface layer of intercellular matter, numerous chondroblasts extend into the joint cavity. From the 27th week on, and particularly in the 37th week, there is a decrease in the number of chondroblasts, which, before birth, form characteristic cell pairs. The cells are set in depressions separated from the neighbouring area with a groove. Depressions and grooves are the result of a collapsed pericellular matrix, elevations rest on a sublayer of chondroblasts. Ultrastructure, human articular cartilage, prenatal development Articular cartilage if formed from the mesenchyme during the development of the skeleton as a part of the cartilaginous blastema of the bone primordium, which is made into a definite bone in the course of ossification. From developmental, microscopic and functional points of view, articular cartilage is a part of the joint, which is in fact a specifically differentiated cleft originating from the above-mentioned mesenchymal blastema. The cartilage thus formed is almost perfectly adapted to perform its function in the organism's locom':ltion. During ossification, the preformed bone primordium is gradually removed. Articular cartilage is not affected by this process and remains intact in the direction afthe joint cavity (Bonucci

show abstract

Section: Discussionsupporting

confidence: 57%

Section: Discussionmentioning

confidence: 99%

Submicroscopic Structure of Human Articular Cartilage in the Period of 19 to 38 Weeks after Fertilization

Horký¹

1991

Acta Vet. Brno

View full text Add to dashboard Cite

show abstract

“…of dysmelia) are not caused by genetic defects, but by unspecified "accidents", involving limb amputation, during embryogenesis. We suggest that explanations for unequal frequencies of congenital phantoms for upper and lower as well as for left and right limbs (Table 2) may ultimately be found in the "laws" governing fetal development -such as the slightly earlier development of upper compared to lower limbs (O'Rahilly and Gardner 1975) and the differential vascularization of left and right limb buds (Bouwes Bavinck and Weaver 1986). With respect to this laterality issue, we note the surprisingly low interest by embryologists, teratologists and developmental neuroscientist in this issue and plead for a closer collaboration across the different medical and psychological disciplines.…”

Section: Phantoms Of Congenitally Absent Limbs As Manifestations Of Amentioning

confidence: 94%

“…Dysmelia is a heterogenous condition affecting the physical integrity of the body (O'Rahilly 1951;O'Rahilly and Gardner 1975). It involves a deficit in limb formation caused by genetic or developmental factors that results in a deformation of arms or legs.…”

Section: Animation Without Incarnation: Phantom Sensations Of Congenimentioning

confidence: 99%

Incarnation and animation: physical versus representational deficits of body integrity

Hilti

Brugger

2009

Exp Brain Res

View full text Add to dashboard Cite

Hilti, L; Brugger, P (2010). Incarnation and animation: physical versus representational deficits of body integrity. Experimental Brain Research, 204(3) AbstractTwo apparently disparate phenomena of defective body integrity are reviewed. The first concerns dysmelia, characterized by the congenital absence or deformation of limbs, and the focus of the review is on phantom sensations of people with this kind of physical integrity disorder. The second phenomenon consists of non-psychotic individuals' desire to have a healthy limb amputated, which is interpreted as a mismatch between the physical integrity of a particular limb and its representation in multimodal cortical areas of the brain. We outlined commonalities and differences between the two conditions and note the absence, in both areas of research, of a unified theory that would account for the reported phenomenology. Phantom limbs in dysmelia and the desire for limb amputation most likely are the consequence of very early developmental dissociations between physical and phenomenal body shapes. They are mirror images of one another in that the former constitutes an "animation without incarnation" and, the latter, an "incarnation without animation". Keywords-body integrity identity disorder (BIID) -paraphilias -parietal lobes -body image, body schema -borderlands of psychiatry and neurology 2 This paper examines two apparently disparate phenomena of corporeal awareness. In both, the completeness or integrity of one's own body is hampered. The first is the occurrence of phantom limbs in individuals born with an "incomplete" body, in which the physical body is incomplete, but the missing limb seems to be represented in the subject's brain, at least as can be inferred from its phenomenal presence. The second phenomenon is the strong desire, by non-psychotic and otherwise well-adjusted healthy individuals, to have a fully functional limb removed. In this condition, it can be argued that despite the physical presence of a limb, the lack of acceptance is due to some underrepresentation in the subject's brain. We review the literature on both conditions and propose that phantom sensations of physically absent limbs and the request for removal of normally developed extremities may be mirror images of one another on the conceptual level: an animation without incarnation and an incarnation without animation, respectively.

show abstract

“…1969: Cihak. 1972: O'Rahilly and Gardner, 1975, The most extensive review of skeletal development in the pre natal foot was completed by Gardner el al. [1959] who examined 184 serially sectioned embryos and fetuses and consulted 104 references.…”

Section: Introductionmentioning

confidence: 99%

Skeletal Relationships in the Human Embryonic Foot Based on Three-Dimensional Reconstructions

McKee¹,

Bagnall²

1987

Cells Tissues Organs

View full text Add to dashboard Cite

Several investigators have reported that the relationships of the embryonic skeletal elements are strikingly different from the adult condition.The present study examined these relationships during the final four stages of the embryonic period (i.e., stages 20–23). Six serially sectioned human embryos, ranging from 21.7 to 34.0 mm crown-rump length, approximately 51–57 postovulatory days, were studied. Three-dimensional reconstruction, involving wax plate and transparency models, was used to recreate the skeletal elements of the embryonic foot, representing each of the four developmental stages by a separate reconstruction. These models provided three different views of the embryonic foot because they were developed from specimens that were sectioned in three different sectional planes. The serial sections of the other two embryos were subsequently studied by microscopic examination. For each of the six embryos, the skeletal relationships were determined, paying particular attention to the arrangement in the hind-foot. These observations were compared with skeletal material of the adult foot which represented the end point of the developmental continuum. In contrast with much of the previous literature the skeletal relationships of the embryonic hindfoot were found to be similar to the adult condition: the fibula projected further distally than the tibia; there was no evidence that the tip of the fibular malleolus was in contact with the calcaneus; and most importantly, the calcaneus was situated below the talus, not beside it as reported by other investigators.

show abstract

The timing and sequence of events in the development of the limbs in the human embryo

Cited by 184 publications

References 48 publications

Submicroscopic Structure of Human Articular Cartilage in the Period of 19 to 38 Weeks after Fertilization

Submicroscopic Structure of Human Articular Cartilage in the Period of 19 to 38 Weeks after Fertilization

Incarnation and animation: physical versus representational deficits of body integrity

Skeletal Relationships in the Human Embryonic Foot Based on Three-Dimensional Reconstructions

Contact Info

Product

Resources

About