Juvenile Body Mass Estimation from the Femur Using Postmortem Computed Tomography Data

Skeletal estimation methods to reconstruct the juvenile biological profile are largely limited to those estimating age, and to a lesser extent, sex. While body mass is not generally estimated as part of the biological profile in forensic investigations, this is a logical candidate for inclusion in the forensic biological profile, as it has long been of interest in paleoanthropology and several methods to estimate juvenile body mass currently exist. To explore the performance of body mass estimation for juveniles, we test the accuracy and precision of previously published panel regression formulae using two femoral measurements: the breadth of the distal metaphysis and the cross-sectional polar moment of inertia (J). The test sample consists of measurements of 94 individuals aged birth to 12.5 years, taken from post-mortem computed tomography scans housed at the Office of the Medical Investigator, New Mexico, USA. Results indicate that body mass estimates are more accurate when estimated from cross-sectional rather than metaphyseal measures. Both formulae, however, consistently underestimate weight, and the magnitude of the underestimation increases exponentially with age. This suggests that contrary to what others have argued, body mass estimation is complicated by population variation in body composition. This study reinforces the importance of documenting and investigating the ontogeny of human variation. The global increase in medical imaging in clinical settings can be leveraged to obtain skeletal data for juveniles from a wide range of ontogenic environments, marking an exciting time for the study of human variation

Prevalence of talon cusps in a Portuguese population: Forensic identification significance of a rare trait

Background: Dental techniques are frequently used in human identification; some of those include comparative analyses of dental features that, being rare or unique to an individual, can establish a positive identification. The usefulness of each feature depends on its population, frequency, and uniqueness. The aim of this study was to determine the prevalence of talon cusps in a Portuguese population. Materials and Methods: A prospective study was performed. Three hundred and two patients were studied, and talon cusps presence was assessed. Statistical tests were carried out using Statistical Package for the Social Sciences (SPSS) 17 software (SPSS Inc., Chicago, IL, USA). Statistical analysis relied primarily on descriptive statistics and crosstabs, with Chi-square analysis. Results: Results showed that talon cusps were observed in only 6.3% of patients. The maxillary lateral incisors were the most common teeth showing this feature (82.1% of all teeth). Conclusion: It can be concluded that talon cusps are an uncommon trait in these Portuguese population, and therefore, it is a feature that can be potentially very useful in forensic human identification, when antemortem dental records are available

Testing the quality of nonadult Bayesian dental age assessment methods to juvenile skeletal remains: The Lisbon collection children and secular trend effects

International audienc

Secular trends in social class differences of height, weight and BMI of boys from two schools in Lisbon, Portugal (1910-2000)

Data on the physical growth of children can provide useful information about the temporal changes in the economic conditions of the society in which they live and the extent of social inequalities within that society as well. Several studies have documented secular changes in the physical growth of children or of adult height, but seldom have the socioeconomic differences in secular trend been reported. The aim of this study is to examine differences in the secular trend of height, weight and BMI of 10-16-year-old boys enrolled in two schools of opposite socioeconomic makeup in Lisbon, Portugal, in the early and late 20th century. The samples from the upper-middle class come from the Colégio Militar, a military boarding school, and the lower-class samples come from the Casa Pia de Lisboa, a residential school for underprivileged boys. While boys from both schools show an approximate increase of 13.6 cm in height, 13.5 kg in weight and 2.4 kg/m2 in BMI, the Casa Pia students were shorter and lighter than their Colégio Militar counterparts throughout the 90-year period. Social class differences in mean height, weight and BMI tend to be greater in 1910 than in 2000, but results are statistically significant for height alone. When the two periods are taken together, Colégio Militar boys differ from their Casa Pia counterparts by approximately 6.4 cm in height, 4.8 kg in weight and 0.4 kg/m2 in BMI. Both samples show a considerable increase in height, weight and BMI but class differences in height, weight and BMI decreased slightly if at all, throughout the 90-year period. This suggests that socioeconomic disparities are persistent, having diminished only slightly since the early 20th century.Social inequalities Physical growth Economic development

Secular change in the timing of dental root maturation in Portuguese boys and girls

International audienc

Age estimation from stages of union of the vertebral epiphyses of the ribs

The research tryp to Lisbon of L.R. was supported by a grant from the Programa de Movilidad de Personal Joven Investigador from the Universidad Auto´noma de Madrid.This study attempts to fill a persistent gap in the literature by documenting the timing of epiphyseal union at the vertebral end of the ribs in a sample of modern Portuguese skeletons. The skeletal remains of 53 females and 45 males, between the ages of 11 and 30, were taken from the Lisbon documented skeletal collection. Individuals in the sample have been previously described as being representative of a middle‐to‐low socioeconomic segment of the early 20th century Lisbon population. Three anatomical locations were examined for epiphyseal union: the head, the articular tubercle and the nonarticular tubercle. The first epiphysis to show partial union is that of the nonarticular tubercle (females, 11–19 years; males, 11–19 years), followed by the epiphysis of the articular tubercle (females, 11–20 years; males, 16–20 years), and finally by the head epiphysis (females, 15–24 years; males, 16–22 years), which can still show incomplete epiphyseal closure at 25 and 24 years for females and males, respectively. A trend for earlier female maturation was observed, but the statistical tests only confirmed this result for some ribs and age groups. No directional asymmetry was found, but a significant fluctuating asymmetry was observed in all three epiphyses. A preliminary analysis showed that the asymmetric group of individuals in the study sample includes all the rural‐to‐urban migrants, relative to the symmetric group. Am J Phys Anthropol,Fundação para a Ciência e Tecnologia. Grant Number: SFRH/BPD/22142/2005Programa de Movilidad de Personal Joven Investigador from the Universidad Autónoma de MadridDepto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEpu

Age estimation from stages of epiphyseal union in the presacral vertebrae

The presacral vertebrae have various secondary centers of ossification, whose timing of fusion can be used for age estimation of human skeletal remains up to the middle to the latter third decade. However, detailed information about the age at which these secondary centers of ossification fuse has been lacking. In this study, the timing of epiphyseal union in presacral vertebrae was studied in a sample of modern Portuguese skeletons (57 females and 47 males) between the ages of 9 and 30, taken from the Lisbon documented skeletal collection. A detailed photographic record of these epiphyses and the age ranges for the different stages of epiphyseal union are provided. Partial union of epiphyses was observed from 11 to 27 years of age. In general, centers of ossification begin to fuse first in the cervical and lumbar vertebrae, followed by centers of ossification in the thoracic region. The first center of ossification to complete fusion is usually that of the mammillary process in lumbar vertebrae. This is usually followed by that of the transverse process, spinous transverse process, and annular ring, regardless of vertebra type. There were no statistically significant sex differences in timing of fusion, but there was a trend toward early maturation in females for some vertebra or epiphyses. Bilateral epiphyses did not show statistically significant differences in timing of fusion. This study offers information on timing of fusion of diverse epiphyseal locations useful for age estimation of complete or fragmented human skeletal remains.Depto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEpu