Skeletal maturation of the human fetus assessed radiographically on the basis of ossification sequences in the hand and foot

The effect of propolis administration on fetal development

Propolis is one of the bee products that widely used in health therapy. However, there has no study evaluating the developmental toxicity of propolis. This study was aimed to analyze the effect of propolis administration during pregnancy on fetal development. The pregnant mice were divided into five groups including control group (Tween 80 1%), low-dose (380 mg/kg b.wt.) and high-dose (1400 mg/kg b.wt.) of water extract of propolis from Banten (WEB), and low-dose (380 mg/kg b.wt.) and high-dose (1400 mg/kg b.wt.) of ethanol extract of propolis from South Sulawesi (EES). Propolis was administered for 18 days of gestation and then sacrificed to analyze the fetal development by examining external and skeletal abnormalities. The histopathological examination of placenta was also conducted. The result showed both low-dose groups did not inhibit fetal development. However, the high-dose of EES significantly reduced the weight, crown-rump of fetuses and increased the number of resorption (p < 0.05). Fetal weight was the only significantly reduced parameter of fetal growth in the highdose group of WEB (p < 0.05). The histopathological examination of placenta showed a reduction of labyrinth development in both high-dose groups. Dose of 380 mg/kg dose of Indonesian propolis is relatively safe for consumption during pregnancy.

The persistence of epiphyseal scars in the adult tibia

Estimation of chronological age from skeletal material is dependent upon estimation of maturational stage observed. Following completion of epiphyseal fusion, a transverse radio-opaque line, termed "epiphyseal scar", may be observed in the region of the former growth plate. According to the literature, this line is likely to become obliterated shortly after completion of epiphyseal fusion. Consequently, presence of an epiphyseal scar has been interpreted as an indication of recent epiphyseal fusion; however, this has not been validated by quantitative research. A study was undertaken to determine persistence of the epiphyseal scars in a cross-sectional population of adults between 20 and 50 years of age. This study examined 1,216 radiographs of proximal and distal tibiae from both sexes and sides of the body. This study suggested that 98.05% of females and 97.74% of males retained some remnant of the epiphyseal scar at the proximal tibia whilst 92.72% of females and 92.95% of males retained some remnant of the epiphyseal scar at the distal tibia. General linear model (GLM) analysis determined that chronological age accounted for 2.7% and 7.6% of variation in persistence of the epiphyseal scar at the proximal and distal tibiae, respectively. This study suggests that obliteration of the epiphyseal scar is not as dependent on chronological age as previously thought. It is, therefore, recommended that this feature not be used as an indicator of chronological age during forensic age assessment.

Sonographic visualization of the middle phalanx of the fetal fifth digit between 13 and 17 weeks of gestation

OBJECTIVE

To assess in utero visualization of the middle phalanx of the fifth digit (MPFD) between 13 and 17 weeks of gestation.

METHODS

This was a prospective cross-sectional study in which women attending for fetal sonographic examination between 13 + 0 and 17 + 6 weeks of gestation were evaluated for the presence of the middle phalanx of the fifth digit (MPFD). A total of 682 fetuses with normal findings on first-trimester anatomical examination were recruited. Using transvaginal multifrequency 4-8 and 5-9 MHz probes, the fifth finger was examined in both axial and lateral views until optimal visualization of the MPFD was achieved.

RESULTS

The MPFD was visualized in 14.3% (2/14) of cases at 13 weeks, 70.3% (154/219) at 14 weeks, 82.2% (240/292) at 15 weeks, 97.4% (111/114) at 16 weeks and 100% (43/43) at 17 weeks of gestation.

CONCLUSIONS

Ultrasound visualization of the MPFD gradually increases during the 13- to 17-week period. This emphasizes the limited role of non-ossification of the MPFD as a sonographic marker of Down syndrome before 17 weeks of gestation.

A histological and radiological investigation of the nasal bone in fetuses with Down syndrome

OBJECTIVES

Previous studies of nasal bone development in Down syndrome have used radiographs or ultrasound for the detection of nasal bone length or nasal bone absence. The aim of this study was to investigate the presence and size of the nasal bones in postmortem Down syndrome fetuses by means of radiographs and histological examination.

METHODS

Thirty-three aborted human fetuses (gestational age 14-25 weeks) with Down syndrome were included. A mid-sagittal tissue block was excised from the skull base to the foramen magnum and along the lateral aspect of the spine. Radiographs of the tissue block were taken in lateral, frontal and axial projections. The length of the nasal bone was measured. The tissue blocks were cut in serial sections and stained. The crown-rump length (CRL), foot length (FL) and number of ossified bones in the hand and foot (CNO) were recorded.

RESULTS

A total of 8/33 fetuses had bilateral nasal bone absence and two had unilateral absence. In fetuses with radiographically diagnosed nasal bone absence, no nasal bone could be found histologically. The majority of the Down syndrome fetuses had CRL, FL and CNO values within the range of those for normal age-matched fetuses. Nasal bone length was normal or reduced.

CONCLUSIONS

Absence of the nasal bone was registered by postmortem examination in one-third of fetuses with Down syndrome. In some fetuses this could be a result of delayed maturation associated with Down syndrome. The phenotypic differences in nasal bone appearance may reflect genotypic differences in the Down syndrome group.

Nerve growth factor receptor immunolocalization during human palate and tongue development

OBJECTIVE

To investigate the temporospatial pattern of nerve growth factor receptor (NGFR) immunolocalization during human palatal closure.

MATERIALS

Human palate and tongue tissues from 33 embryos/fetuses, 9 to 22 weeks of fertilization age.

METHODS

Tissues were divided according to developmental stage and palatal development (before, during, and after closure) and then subjected to decalcification, paraffin embedding, serial sectioning, survey staining, and p75NGFR immunohistochemical staining.

RESULTS

Specific temporospatial patterns of p75NGFR reactivity were observed; reactivity was intense in the soft tissue palatal shelves before and during palatal closure and was weaker in the palate after palatal closure. In the tongue, intense reactivity was seen throughout 9 to 22 weeks.

CONCLUSION

The observed patterns suggest that p75NGFR may enable the visualization of physiological events in palatal closure during normal human development.

Aspects of skeletal development in fragile X syndrome fetuses

The purpose of the present investigation was to describe the skeletal development in prenatal fragile X syndrome. We studied fetuses (4 males, 2 females), with gestational ages (GA) 12-14 weeks, from 5 unrelated, different, known carrier mothers. Because of trauma to the fetus during abortion, different parts of the 6 fetuses were available for investigation. The vertebral column and the facial skeleton of all the fetuses were examined, the feet and hands of 5 fetuses, and the cranial base of 3 fetuses. The tissue remnants were examined radiographically and histochemically, and the results compared with previously published normal findings. Radiographic findings included normal ossification sequence, except for 1 fetus where there was an abnormal sequence in the first finger; normal morphology of ossification centres; and nasal bones were absent in the 5 fetuses and present in 1 (14 weeks of gestation). The histological study suggests presence of an acid mucopolysaccharide malfunction in the supporting tissue, because the normal cartilage resorption and orthochromatic cartilage reactions do not appear during the initial enchondral ossification. In addition, the apoptosis of ectodermally derived cells (notochord and palatal epithelial layers) appears delayed or abnormal. The sella turcica was malformed in the 2 fetuses investigated for sella turcica morphology.

Fetal age: methods of estimation and effects of pathology

Accurate identification of fetal age is important in a wide variety of circumstances. Seventeen anthropometric and radiographic measurements were taken on fetuses between 15 and 42 weeks of gestational age, both with and without pathologic conditions. A full evaluation including radiographic, karyotypic, gross anatomic, and histologic examination of the fetus and placenta identified 72 individuals as nondysmorphic with no signs of chronic uterovascular insufficiency. These specimens served as the control group. Based on least-squares regressions of this group, age-estimation equations were calculated for all variables. Six models were adequately described by linear equations; the remaining 11 required a quadratic term. Based on standard error of the estimate (S(y:x)), skeletal measures proved the most accurate age estimators. Pathologic conditions were shown to have an influence on age estimation indicated by high levels of inaccuracy and, in some instances, significant bias.

Abnormal timing in the prenatal ossification of vertebral column and hand in Crouzon syndrome

We report on a radiographically examined fetus (gestational age 13 weeks) with Crouzon syndrome caused by a mutation in the gene encoding the fibroblast growth factor 2 (FGFR2). We found an approximately 2-week delay in vertebral body and hand ossification with normal vertebral arch ossification, suggesting that regionally delayed skeletal maturation might be a manifestation of FGFR2 mutation syndromes. The findings support other studies indicating that different signaling pathways control skeletal maturation in vertebral bodies and vertebral arches.

Pituitary gland and sella turcica in human trisomy 21 fetuses related to axial skeletal development

The purpose of the present investigation was to study the sella turcica/pituitary gland region in trisomy 21 fetuses and to relate the findings in the region to the ossification pattern in the axial skeleton formed by the cranial base and spine. Material from 22 human fetuses with trisomy 21, CRL 80 mm to CRL 190 mm, corresponding to gestational ages from 14 to 21 weeks, was examined and compared with material from gestation-matched normal controls. After radiography, tissue blocks from the cranial base, including the pituitary gland, were examined and compared with those of normal fetuses. Four different types of sella turcica/ pituitary gland morphology were observed. Thirteen fetuses (Type I) were morphologically normal. Minor abnormalities occurred in the sella turcica and pituitary gland (adenopituitary gland tissue pharyngeally) in six fetuses (Types II and III). There was agreement between the histologically recorded deviations in the sella turcica and the radiographic observations of the basisphenoid bone. In three cases (Type IV) out of 22, more pronounced structural abnormalities occurred in the sella turcica, and radiographically the basisphenoid bone appeared cleft. All sella turcica changes observed in trisomy 21 were situated anteriorly in the base of the sella. In all cases the basilar part of the occipital bone was normal. Minor changes in the sella turcica region were mainly accompanied by cervical vertebral abnormalities, while the most severe abnormalities occurred in association with malformations in the lumbar vertebrae. There was no association between sella turcica malformations and the absence or presence of the nasal bone.

Prenatal development of the normal human vertebral corpora in different segments of the spine

STUDY DESIGN

Vertebral columns from 13 normal human fetuses (10-24 weeks of gestation) that had aborted spontaneously were investigated as part of the legal autopsy procedure. The investigation included spinal cord analysis.

OBJECTIVES

To analyze the formation of the normal human vertebral corpora along the spine, including the early location and disappearance of the notochord.

SUMMARY OF BACKGROUND DATA

Reference material on the development of the normal human vertebral corpora is needed for interpretation of published observations on prenatal malformations in the spine, which include observations of various types of malformation (anencephaly, spina bifida) and various genotypes (trisomy 18, 21 and 13, as well as triploidy).

METHODS

The vertebral columns were studied by using radiography (Faxitron X-ray apparatus, Faxitron Model 43,855, Hewlett Packard) in lateral, frontal, and axial views and histology (decalcification, followed by toluidine blue and alcian blue staining) in and axial view. Immunohistochemical marking with Keratin Wide Spectrum also was done.

RESULTS

Notochordal tissue (positive on marking with Keratin Wide Spectrum [DAKO, Denmark]) was located anterior to the cartilaginous body center in the youngest fetuses. The process of disintegration of the notochord and the morphology of the osseous vertebral corpora in the lumbosacral, thoracic, and cervical segments are described. Marked differences appeared in axial views, which were verified on horizontal histologic sections. Also, the increase in size was different in the different segments, being most pronounced in the thoracic and upper lumbar bodies. The lower thoracic bodies were the first to ossify. The morphologic changes observed by radiography were verified histologically.

CONCLUSIONS

In this study, normal prenatal standards were established for the early development of the vertebral column. These standards can be used in the future--for evaluation of pathologic deviations in the human vertebral column in the second trimester.

Human fetal hand size and hand maturity in the first half of the prenatal period

The purpose of the present study has been to establish radiographic standards of hand length and finger bone size in the first half of the prenatal period, and to relate these measurements to general fetal size (CRL) and foot length (FL), as well as to the skeletal maturity assessed from a Composite Number of Ossified bones in hand and foot radiographs (CNO). The right hand and foot of each of 251 normal human fetuses (CRL 47-194 mm) were radiographed. From each hand radiograph hand length (DM), third proximal phalangeal bone length (PP) and third metacarpal bone length (MC) were measured. The study showed that third proximal phalangeal and metacarpal bone lengths both provide a valuable basis for estimating hand length. Both hand length and the length of the third metacarpal bone were found to be good predictors of general fetal size (CRL). The study provides standards for the relationships between hand and finger bone sizes, general fetal length and foot length. By combining third metacarpal bone size and skeletal maturity of the hand and foot general fetal development (age and crown-rump length) can be estimated. Insight into normal hand size and finger bone size at different stages of normal development including skeletal maturation is useful in future evaluation of handsize under pathological conditions.

Palate structure in human holoprosencephaly correlates with the facial malformation and demonstrates a new palatal developmental field

In this study we analyzed palate structure in holoprosencephaly and correlated it with the facial malformations. Eleven human holoprosencephalic fetuses (three cyclopic, two ethmocephalic, one cebocephalic, four with median cleft lip, and one with short philtrum) at 17-23 weeks of gestation and three children (age 2 1/2, 6 and 7 years) with a single central incisor were studied. Photographic and radiographic methods were used. We found that in holoprosencephaly palate structure is abnormal. The severity of this malformation decreases with decreasing severity of facial malformation. Thus, the study shows a close relationship between the facial and the palatal malformation. In all phenotypes the premaxillary area is malformed. From this region, a fan-shaped field along the midpalatal suture is involved in all facial phenotypes, the fan being broadest in cyclopia and narrowest in the short philtrum malformation. A similar fan-shaped field can be discerned in the face, where the broadest fan also indicates the greatest severity with cyclopia, and the narrowest fan the least severe median lip malformation. In the palate field, the anteroposterior furrows seemingly demarcate the field. The findings may be of importance for the future evaluation of palatal malformations in children.

Pattern of malformations in the axial skeleton in human triploid fetuses

We examined the axial skeleton in 15 human triploid fetuses (10 with XXX and 5 with XXY sex chromosomes). All fetuses 14-29 weeks of gestational age (GA), underwent whole-body radiography, permitting analysis of the nasal bone and the spine. From 9 of these, detailed radiographs were taken of midsagittal blocks of the cranial base and the spine, permitting detailed analysis of the cranial base.

NASAL BONE

Of 14 fetuses, where the nasal bone was seen on lateral projection, it appeared short in 10 cases.

SPINE

The spine was normal in 7 of 15 fetuses; malformations occurred in 8. These were osseous fusions between 2 or more vertebral bodies, most frequently in the cervical and thoracic regions, and disproportions in the sizes of the cervical bodies. Fusions occurred in 5 cases alone, and in one case in combination with disproportions of vertebral size. Disproportions alone occurred in 2 cases.

CRANIAL BASE

Malformation of the basilar part of the occipital bone was found in 5 of the 9 fetuses investigated. Of 9 fetuses, bilateral ossification centers of the postsphenoid bone occurred in 7, and shell-like ossification centers in 2. There was no difference in the type of malformations in the different axial fields related to genotype (XXX and XXY).

CONCLUSION

The most remarkable findings in the axial skeleton of triploid fetuses are vertebral fusions in 6 of 15 cases; clefts of vertebral bodies, previously reported as common findings in trisomy fetuses, are not demonstrated.

Pattern of malformations in the axial skeleton in human trisomy 13 fetuses

The purpose of this study was to analyse the development of the axial skeleton in human trisomy 13 fetuses and to define which fields in the axial skeleton are affected in this condition. We investigated nine human fetuses with trisomy 13 and gestational ages of 14-19 weeks. Whole body radiographs and radiographs of midsagittal tissue blocks of the cranial base and the spine were studied. In the youngest fetus, 14 w GA, no malformations were observed. In eight fetuses, 17-19 weeks GA, malformations occurred in the lumbosacral spine. In four fetuses additional malformations were observed in the thoracic spine. The study showed that there was a correspondence between the extent of malformation in the lumbosacral spine and the thoracic spine. When mild malformation occurred in the lumbosacral region, no malformation was observed in the thoracic region, whereas malformation was observed in the thoracic region when there was extensive malformation in the lumbosacral region. Malformations did not occur in the cervical spine or the basilar part of the occipital bone, but the postsphenoidal part of the sphenoid bone was small and irregular in the six cases where it could be examined. In seven fetuses there was malformation or agenesis of the nasal bone. This pattern of axial skeletal malformations in trisomy 13 fetuses was not described previously. Comparisons are made with previous studies of the fetal axial skeleton in trisomy 18 and trisomy 21, where the pattern of malformations was different. We reiterate our recommendation that axial skeletal radiography should be part of the postmortem examination of fetuses with suspected or verified chromosome abnormalities.

Pattern of malformations in the axial skeleton in human trisomy 18 fetuses

We examined and described the development and abnormalities of the axial skeleton in 10 human trisomy 18 fetuses. Whole-body radiographs and radiographs of midsagittal tissue blocks of the cranial base and the spine were studied. In 3 fetuses no spinal radiographs were available. Seven osseous regions or fields along the body axis were analyzed, four in the spine, and three in the cranial base and nasal bones. Malformations occurred in the occipital field in all fetuses. This was a characteristic notching, either unilateral or bilateral, of the basilar part of the occipital bone. Nasal bones were abnormal in 8 cases, either absent or hypoplastic. Malformations were found in the thoracic and/or lumbosacral field in 7 fetuses. A single abnormality was found in the cervical spine in one fetus. The pattern of axial skeletal malformation in trisomy 18 fetuses recorded in the present study has not been described previously. Axial skeletal radiography should be included in autopsies of fetuses when chromosome disorders are present or suspected. The methods applied here are unaffected by autolysis.

Axial skeleton and pituitary gland in human fetuses with spina bifida and cranial encephalocele

The purpose of this study was to investigate the axial skeleton and the pituitary gland in fetuses with spina bifida or cranial encephalocele in order to elucidate the pathogenesis of the conditions. The findings were related to former investigations performed on normal fetuses and on fetuses with anencephaly and rachischisis. Eight human fetuses from spontaneous or therapeutic abortions, 11-28 weeks of gestational age, were investigated. Radiographs were taken of the axial skeleton and histological investigation, including immunohistochemical marking for thyroid-stimulating hormone was performed on tissue blocks of the cranial base, including the sella turcica and the pituitary gland. Radiography revealed only minor malformations in the axial skeleton and not in all cases. The types of malformations resembled those seen in anencephaly and rachischisis. Histological investigations revealed severe malformations in the sella turcica region in spina bifida and minor ones in cranial encephalocele. Pharyngeally located adenopituitary gland tissue occurred in all fetuses. Anencephaly and cranial encephalocele seemingly are conditions resulting from different expressivity of the same multifactorial process of maldevelopment involving mesoderm (skeleton), neurectoderm (spinal cord and brain), and surface ectoderm (adenopituitary gland tissue). It is suggested that the molecular biological signaling between the notochord, the scleroderm, and the surface ectoderm is disturbed in spina bifida and cranial encephalocele.

Postmortem axial skeletal radiography can reveal fetal CNS malformations

The routinely performed autopsy of a macerated fetus will often be of dubious value, particularly as regards the examination of the central nervous system (CNS). Former studies have demonstrated a close relationship between certain CNS malformations and axial skeletal malformations revealed radiographically. In the present report a postmortem examination of a severely macerated fetus demonstrates a transsphenoidal encephalocele. A supplementary histological examination confirmed this condition and furthermore revealed absence of the pituitary gland. The findings were related to a strongly elevated serum alphafetoprotein level in the 18th gestational week. This report emphasizes the value of postmortem axial skeletal radiography of autolyzed fetuses suspected for CNS malformations.

Human prenatal craniofacial development related to brain development under normal and pathologic conditions

A survey is given of current knowledge of the interrelationship between facial, cranial and brain development in humans. First, normal facial, cranial (mandible, maxilla, palatine bone, cranial base, theca cranii, dentition), and brain development are described separately. Then, developmental interrelationships are illustrated under normal and pathologic conditions (cleft lip and palate, holoprosencephaly, anencephaly, amniotic band sequence). New observations are described in detail, and references are given to previously published articles. A close interconnection exists between the development of the face, the craniofacial skeleton, and the brain. This is illustrated by new observations in cleft palate fetuses and new theories about the etiology of holoprosencephaly and tooth agenesis. The survey focuses, moreover, on the importance of the face and the cranial base in endocrine development. Borderlines between face regions and cranial regions with different developmental origin are set up for future elucidation of the etiology behind syndromes involving the craniofacial regions.

On the presence of a secondary cartilage in the mental symphyseal region of human embryos and fetuses

The presence of a secondary cartilage in the mental symphyseal region was examined in this study. A double-staining method with alcian blue and alizarin red S was performed on both whole human embryos and fetuses (developmental age between 8 and 17 weeks, crown-rump length, CRL, between 37 and 124 mm) and their disjointed mandibles. Histological and histochemical techniques were applied to transverse serial sections of whole disjointed fetal heads. The ossification process observed in the mental symphysis is quite different from that of the mandibular body, whose membranous ossification is induced by the contiguous Meckel's cartilage. No evidence of any fusion of Meckel's cartilage with the symphyseal cartilage, that lies within the symphyseal space, was detected. On the basis of these findings, we suggested that the mental secondary cartilage is able to change into bone according to an endochondral ossification process. Moreover, the role of mechanical causes in the development of the mental symphysis was hypothesized.

Diagnostic distinction between anencephaly and amnion rupture sequence based on skeletal analysis

The axial skeletal development of eight second trimester aborted fetuses, clinically diagnosed as amnion rupture sequence with cranial involvement, was examined radiographically and histologically. Three of the eight fetuses showed axial skeletal malformation in the spine and the craniofacial skeleton corresponding to the malformations seen in anencephaly. These are vertebral body malformations, consisting of double corpora and of osseous malformations in the components of the cranial base, the corpus of the occipital bone, and the postsphenoid bone. These types of malformation, which have previously been described, are located along the original course of the notochord. The findings show that it is possible by means of radiography of the axial skeleton to distinguish between anencephalic fetuses which become secondarily involved in amnion rupture and fetuses which were initially normally developed. The method supplements detailed fetal examination and provides important information for genetic counselling.

The midline craniofacial skeleton in holoprosencephalic fetuses

Craniofacial skeletal development in eight human holoprosencephalic fetuses from second trimester abortions were examined by radiography and histology. The whole spectrum of associated facial malformations from anophthalmia through cyclopia, ethmocephaly, cebocephaly, and median cleft lip to short philtrum was represented. Cases with the most severe facial malformations also had the most severely affected facial skeleton. In the facial skeleton, the premaxilla was most often affected; it was absent in seven cases and malformed in the one with only a short philtrum. This and other facial skeletal malformations can be explained as abnormal fusion of the facial bones because of defective development of the nasal cartilage. The occipital bones were normal, but the basicranial skeleton anterior to the spheno-occipital junction was affected in all cases. The findings support the hypothesis that the facial malformations in holoprosencephaly result from disturbance in embryonal life of the mesoderm at the rostral end of the notochord.

Simple autopsy method for analysis of complex fetal cranial malformations

A new radiography technique for examining second trimester abortions permits an accurate analysis of growth and maturation of the fetal skull. Reference material for normal development has been previously published. The potential of the method is demonstrated with three examples: thanatophoric dysplasia, Arnold-Chiari malformation, and anencephaly.

Tubular hand bone growth during the latter half of the prenatal period: an allometric analysis

The growth of the 19 tubular hand bones from fetal months 5 to 9 was studied by the allometric method. The hand bones were carefully dissected under a low power stereoscopic microscope. The length and breadth of all bones was found to be monophasic in relation to crown-rump length. In general, maximum bone and ossified shaft lengths in the same row group demonstrate similar allometric coefficients. The specific growth rate of ossified shaft length for all fetal hand bones is greater than the growth rate of maximum length. The highest allometric coefficients for both maximum length and ossified shaft length were obtained from the middle phalanges. The shape of the metacarpals and distal phalanges becomes thinner, while the other bones become thicker or maintain their length-breadth ratio. The relative growth pattern of the first proximal phalanx differed from the middle phalangeal group of the other digits. This suggests that current nomenclatures for the three bones of the pollex is appropriate.

Development of deciduous mandibular incisors related to developmental stages in the mandible

On the basis of morphological and histochemical studies of 71 human mandibles from the former half of prenatal life, five stages (D I to D V) in the development of the deciduous mandibular incisors are described. These stages are related partly to general parameters of fetal development, such as M age (menstrual age), CRL (crown-rump length), CNO (composite number of ossified bones in hand and foot) and partly to stages in the skeletal development of the symphysis menti (SM I to SM V). The investigation revealed close relationship between the development of the deciduous mandibular incisors and the skeletal development of the deciduous mandibular incisors and the skeletal development of the mandible in the region of the incisors. No such relationship was found between the development of the deciduous mandibular incisors and general parameters of fetal development.

Developments in the identification of human skeletal material (1968-1978)

A review of publications over the last ten years of methods in the field of physical anthropology for determining age, sex, race and stature of human skeletal material is presented. Comparisons are made with the types of papers published in the previous ten years (1958-1968) in six categories: (1) Visual examination of bones (2) Anthropometric measurements of bones (3) Anthropometric measurements with subsequent use of statistics in the form of discriminate function analyses (4) Time and sequence of eruption of the teeth (5) X-ray examination of the internal structure of bone sections (6) Microscopic examination of the internal structure of bone.

Relation between symphyseal and condylar developmental stages in the human fetus

In 51 human fetuses from the first half of the prenatal period, developmental stages in the symphysis menti and the mandibular condyle were assessed by histochemical reactions. The study showed the association between the timing of the developmental stages in the two mandibular growth zones.

Histochemical and radiologic studies of the human fetal mandibular condyle

Histochemical investigations on the mandibular condyle were performed on 72 human embryos and fetuses of crown-rump lengths (CRL) ranging from 26 to 186 mm, representing skeletal maturity indices expressed in CNO values (CNO = composite number of ossified bones in the hand and foot) ranging from 0-0 to 19-12. The development of the mandibular condyle is described according to morphology and to histochemical reactions for glycosaminoglucuronglycans, collagen, glycogen, alkaline and acid phosphatase, and nonspecific AS esterase. The development is described for (1) the bony component of the mandibular condyle, (2) the condylar cartilage, and (3) the fibrous cover of the mandibular condyle. For each tissue component, maturation steps are set up and included in the total evaluation of the condylar maturity stages. The developmental sequence set up on the basis of the morphologic and histochemical findings was followed by all condyles investigated. From this it may be presumed that the developmental sequence in human mandibular condylar components is constant during the former half of the prenatal period. The material available did not justify a description of skeletal development in the mandibular condyle as a function of fetal size, CRL, or skeletal maturity in the hand and foot.

Ossification in the hand and foot of the macaque (Macaca nemistrina). I. General features

The appearance of the secondary centers of ossification was investigated in hand and foot radiographs of 112 fetal and neonatal Macaca nemestrina and a maturational index calculated using a scoring system that differentiated between the initial and later stages of ossification. Cumulative incremental curves of skeletal maturation, constructed by plotting the maturational indices against gestational age, demonstrated three distinct periods of ossification: the First Acceleration when primary centers appear, the Plateau, and the Second Acceleration when the secondary centers ossify. Similar curves are constructed for human prenatal and postnatal ossification. The results are also compared with those reported for M. mulatta, and the bases of the observed differences are discussed. Compared with other primates, the fetal and neonatal macaque shows a developmental precocity which may be an ontogenetic adaptation to the socioecological setting of terrestrial life.

Early prenatal attainment of adult metacarpal-phalangeal rankings and proportions

As shown in 56 human embryos and fetuses between 15 and 104 mm in crown-rump length, "adult" metacarpal-phalangeal length rankings are attained by the seventh intrauterine week and near-adult bone-to-bone ratios or proportions by the theirteenth week. Micrometric measurements of optically-projected histological hand sections show relative elongation of the distals between the 15-29 mm and 30-44 mm crown-rump range, and relative reduction to radiogrammetrically-determined adult proportions by the 90-104 mm CRL.