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OBJECTIVES Recent investigations have evaluated the influence of body composition on long bones in order to overcome the limits of body mass (BM) estimation methods and eventually lead to studying nutrition in past populations. Knowing how fat mass (FM) and fat-free mass (FFM) impact the skeleton would also enhance the understanding of mobility, activity, and locomotion derived from bone architecture. We investigated the relationship between BM and composition, and the architecture of the entire tibial and femoral diaphyses in an adult sample representative of a wide range of variation in age, BM, and composition. MATERIALS AND METHODS Body composition was measured directly from 78 whole-body CT scans for which the age, sex, BM, and stature were recorded. The entire diaphyseal thickness, volume, curvature, and cross-sectional geometry parameters of both the femur and tibia were numerically extracted. RESULTS FM correlates with large portions of the femoral thickness in females only. FFM correlates with the femoral diaphysis in males but not in females. FFM correlates with the tibia architecture in both sexes, while FM is correlated in males exclusively. DISCUSSION BM and body components influence the architecture of the diaphysis of lower limb long bones in sex-specific patterns that are mostly reflected in their thickness and can be recorded, in some cases, for their strength, rigidity, and volume. Our results suggest that (1) long bone diaphyses should be thoroughly studied, as a whole, when possible; and (2) BM and body components should be accounted for when deriving activity, mobility, or locomotion patterns from cortical bone.

Previous studies have reported that the ageing method of Suchey-Brooks (pubic bone) and some of the features applied by Lovejoy et al. and Buckberry-Chamberlain (auricular surface) can be confidently performed on 3D visualizations from CT-scans. In this study, seven observers applied the Suchey-Brooks and the Buckberry-Chamberlain methods on 3D visualizations based on CT-scans and, for the first time, on 3D visualizations from laser scans. We examined how the bone features can be evaluated on 3D visualizations and whether the different modalities (direct observations of bones, 3D visualization from CT-scan and from laser scans) are alike to different observers. We found the best inter-observer agreement for the bones versus 3D visualizations, with the highest values for the auricular surface. Between the 3D modalities, less variability was obtained for the 3D laser visualizations. Fair inter-observer agreement was obtained in the evaluation of the pubic bone in all modalities. In 3D visualizations of the auricular surfaces, transverse organization and apical changes could be evaluated, although with high inter-observer variability; micro-, macroporosity and surface texture were very difficult to score. In conclusion, these methods were developed for dry bones, where they perform best. The Suchey-Brooks method can be applied on 3D visualizations from CT or laser, but with less accuracy than on dry bone. The Buckberry-Chamberlain method should be modified before application on 3D visualizations. Future investigation should focus on a different approach and different features: 3D laser scans could be analyzed with mathematical approaches and sub-surface features should be explored on CT-scans.

Laboratory of Biological Anthropology, Department of Forensic Medicine, The Panum Institute,University of Copenhagen, 2200 Copenhagen, DenmarkKEY WORDS osteon population density (OPD); femur; histomorphometry; bone microscopyABSTRACT Unbiased selection of regions of inter-est (ROIs) and unbiased definition of histological struc-tures are needed to improve the repeatability of micro-scopic methods for age at death determination and toreduce operator subjectivity. We present resultsobtained by selecting ROIs according to stereologicalprinciples on a sample of 28 femoral cross sections ofCaucasoid males aged 20–89 years. A regular grid wasoverlaid on the cross section, and the ROIs wereselected as close as possible to the periosteum in theanterior, lateral, and medial regions. The areas consist-ing of all intact secondary osteons plus fragments wereoutlined and osteon population density, percent osteonpopulation, area, and perimeter were calculated usingstereological methods and software. Overall, the analy-ses of intra- and inter-section variability showed nosignificant difference between the ROIs, i.e., the loca-tion within the cross section of the ROIs does notaffect the outcome of the analyses. The individual vari-ability was found to be higher in adults aged 30–55years than in other age ranges. Am J Phys Anthropol000:000–000, 2010.

The effectiveness of the so-called skeletal markers of activity as functional indicators is widely debated. Among them, certain morphological features of the anterior aspect of the femoral head-neck junction (Poirier’s facet, cervical fossa of Allen, etc.) have been considered in relation to some behaviors and specific activities (e.g., squatting, horseback riding, etc.). However, disagreement on terminology and descriptions, the absence of standardized scoring methods and poor knowledge of the variability and distribution of these features make it difficult to interpret their meaning. The aim of this study is to analyze the variability of the anterior aspect of the femoral neck through a new scoring method taking into account three main traits: Poirier’s facet, plaque, and cribra (including the Allen’s fossa). This method has been applied to a sample of 225 adult individuals of both sexes coming from an identified modern skeletal collection, achieving low intraobserver and interobserver error values. The results highlight some significant trends: plaque, almost always bilateral, appears to be a normal condition of the femur, being present in approximately 90% of the individuals. Cribra is more frequent in females and decreases with age. Poirier’s facet shows a very low frequency. This method allows the representation of both the anatomical diversity of the region already described in literature and part of the variability never considered before. Our results suggest caution in considering these features as markers related to specific activities.

The effectiveness of the so-called skeletal markers of activity as functional indicators is widely debated. Among them, certain morphological features of the anterior aspect of the femoral head-neck junction (Poirier's facet, cervical fossa of Allen, etc.) have been considered in relation to some behaviors and specific activities (e.g., squatting, horseback riding, etc.). However, disagreement on terminology and descriptions, the absence of standardized scoring methods and poor knowledge of the variability and distribution of these features make it difficult to interpret their meaning. The aim of this study is to analyze the variability of the anterior aspect of the femoral neck through a new scoring method taking into account three main traits: Poirier's facet, plaque, and cribra (including the Allen's fossa). This method has been applied to a sample of 225 adult individuals of both sexes coming from an identified modern skeletal collection, achieving low intraobserver and interobserver error values. The results highlight some significant trends: plaque, almost always bilateral, appears to be a normal condition of the femur, being present in approximately 90% of the individuals. Cribra is more frequent in females and decreases with age. Poirier's facet shows a very low frequency. This method allows the representation of both the anatomical diversity of the region already described in literature and part of the variability never considered before. Our results suggest caution in considering these features as markers related to specific activities.