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- Sex estimation with the total area of the proximal femur: A densitometric approachPublication . Curate, Francisco; Albuquerque, Anabela; Ferreira, Izilda; Cunha, EugeniaThe estimation of sex is a central step to establish the biological profile of an anonymous skeletal individual. Imaging techniques, including bone densitometry, have been used to evaluate sex in remains incompletely skeletonized. In this paper, we present a technique for sex estimation using the total area (TA) of the proximal femur, a two-dimensional areal measurement determined through densitometry. TA was acquired from a training sample (112 females; 112 males) from the Coimbra Identified Skeletal Collection (University of Coimbra, Portugal). Logistic regression (LR), linear discriminant analysis (LDA), reduce error pruning trees (REPTree), and classification and regression trees (CART) were employed in order to obtain models that could predict sex in unidentified skeletal remains. Under cross-validation, the proposed models correctly estimated sex in 90.2-92.0% of cases (bias ranging from 1.8% to 4.5%). The models were evaluated in an independent test sample (30 females; 30 males) from the 21st Century Identified Skeletal Collection (University of Coimbra, Portugal), with a sex allocation accuracy ranging from 90.0% to 91.7% (bias from 3.3% to 10.0%). Overall, data mining classifiers, especially the REPTree, performed better than the traditional classifiers (LR and LDA), maximizing overall accuracy and minimizing bias. This study emphasizes the significant value of bone densitometry to estimate sex in cadaveric remains in diverse states of preservation and completeness, even human remains with soft tissues. (C) 2017 Elsevier B. V. All rights reserved.
- Femoral cortical bone in a Portuguese reference skeletal collectionPublication . Curate, Francisco; Cunha, EugeniaThis study aims to investigate patterns of femoral cortical bone fragility with age (at death) and to evaluate its associations with sex and bone mineral density. Radiogrammetric parameters of the femur and bone mineral density at the proximal femur were assessed in an adult sample (N=98) from the Coimbra Identified Skeletal Collection (Portugal). Diaphysis total width (DTW), femoral cortical index (FEMCI) and bone mineral density (BMD) are significantly higher in males, while medullary width (MW) is not statistically different between sexes. Cortical bone parameters of the femoral diaphysis are associated with age only in women, whereas BMD decreases with age in both sexes. The evaluation of femoral cortical bone reveals sex-specific trajectories of endosteal bone loss and periosteal apposition, stemming from sexual differences in the rate and pattern of bone loss, and in bone size. In females, endocortical bone loss rises with age, particularly in peri- and postmenopausal years, decelerating later in life. Concomitantly, accretion of bone in the subperiosteal surface persists throughout adulthood - partially offsetting bone fragility in women. Strength in the femoral mid diaphysis appears to be pre served throughout most of the life course in both sexes.
- Cortical bone loss in a sample of human skeletons from the Muge Shell middensPublication . Umbelino, Cláudia; Curate, Francisco; Perinha, Andreia; Ferreira, Teresa; Cunha, Eugenia; Bicho, NunoThe Muge shell middens of Cabeco da Arruda, Cabeco da Amoreira and Moita do Sebastiao (central Portugal) have been key sites of archaeological research for 150 years, possibly working as residential sites occupied by semi-sedentary communities during the final Mesolithic. The purposes of this article include the biocultural assessment of metacarpal cortical bone fragility and its associations with age at death, sex and osteoporotic fractures in the Portuguese Mesolithic, as well as a diachronic comparison of cortical bone health in Mesolithic (N = 34) and modern reference (N = 219) samples. Cortical bone at the Muge shell middens displays age and sex-specific trajectories of periosteal apposition and endosteal bone loss, most likely associated with hormonal and behavioural/cultural influences. Metacarpal endocortical bone loss seems to increase with age at death in females, with a simultaneous expansion of the diaphysis. The overall pattern of cortical bone health is similar to the pattern observed in a reference skeletal collection, but elderly women from Muge seem to lose less cortical bone than late twentieth century counterparts from Coimbra. Two older males exhibited vertebral compression fractures, but only one is possibly related with bone fragility.