Academic literature on the topic 'Human Sex Determination'

Thesis (M.S.F.S) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.<br>This study compares sexual variation of the human skeletal pelvis through geometric morphometric analyses. Digitization of the skeletal elements provides the framework for a multi-faceted examination of shape. The sample used in the study consists of individuals from the Bass Donated Skeletal Collection, located at the University of Tennessee-Knoxville. Landmarks digitized for the study are derived from the 36 points implemented in Joan Bytheway and Anne Ross’s geometric morphometric study of human innominates (2010). The author hypothesizes that morphological variation between males and females will be visible to varying degrees throughout the pelvis, with structures to be compared consisting of the ilium, ischium, pubis, obturator foramen, and acetabulum. Particular attention will be paid to the pelvic canal, as this area seems to carry the most sex-specific function of the bone. It is hypothesized that structures directly contributing to the pelvic canal will be more sexually dimorphic than peripheral structures. Data points plotted throughout the pelvis will allow for comparison of various regions. Results indicate that the innominate can be divided into modules with relatively low levels of covariation between them. Greatest amounts of sexual dimorphism are located at the pubis and ischium. The shape of the acetabulum and obturator foramen display little variation between the two sexes. Areas that have the potential for sex determination could be investigated more thoroughly in the future and may be of use in forensic cases in which remains are incomplete.<br>2031-01-01

The identification of the sex and age-at-death of an individual is of primary importance in the analysis and description of adult human skeletal remains in both forensic and archaeological contexts. Many current methods of sex and age determination have been derived on a very small number of skeletal collections and critical evaluations of their reliability on material of different provenance have been few. The purpose of this investigation was to evaluate the utility of methods (a) in widespread use for age and sex estimation, or (b) even if not in widespread use but offering particular advantages and (c) derived during the course of this investigation with a view designed to improving accuracy of prediction and ease of application. Three European skeletal series of documented age and sex of different temporal origins were used for this evaluation. Only non-destructive tests were evaluated. For sex determination metric and non-metric observations from the innominate were tested, as it is generally considered the most dimorphic area of the adult skeleton. The discriminatory potential of long bone dimensions was also assessed since they tend to survive inhumation better than the innominate and may be the only skeletal material represented in fragmentary remains. Pubic symphyseal metamorphosis is probably the most frequently used method for age-at-death estimation and its utility as a predictor of chronological age was examined as was the degree of degenerative joint disease as evidenced from the long bones. A method was devised based on estimates of bone loss from radiographs and densitometric traces of the humerus. It provided the lowest standard error of estimate in age-at-death assessment. Many of the methods in current use proved less efficient in sex and age identification in the samples investigated than on the material on which they were derived. The reasons for this, and the implications for the reconstruction of biological identity from skeletal remains are discussed and recommendations for age and sex estimations on the innominate and long bones are made.

One of the main problems in reconstructing the biological profile of unidentified human remains is the reliability of the methods used. These methods are normally developed on modern identificated human skeletal collections, but human variability can introduce problematic biases when applied on osteological collections from different geografical and cronological contexts. This study test the reliability of selected macroscopic methods for sex determination: the index of sexualization of Acsadi and Nemeskeri, the Phenice method and for the age estimation: the synostosis of cranial sutures (Meindl and Lovejoy), the morphological variations at the pubic symphysis (Suchey and Brooks), the morphological variations at ileum surface (Lovejoy, et al.), the modifications of the sternal end of the fourth rib (Iscan et al.) and the variations of the degree of sacral vertebral body fusion (Belcastro et al.) on a large sample (n.489) of know sex and age from Certosa Cemetery of Bologna and “Colecção Esqueletos Identificados" of Coimbra. Regarding age, for each method was calculated the standard values of bias and inaccuracy. The method of pubic symphysis might be the most reliable for age estimation but we must consider the width of age ranges considered by the method. The values of inaccuracy are over 10 years in individuals older than 50 and 27 years in individuals older than 60. The index of sexualization confirm in more than 99% of cases the known sex and the Phenice method gave good results with the 87% of confirm. The reliability of the tested methods in the two european populations was confirmed, with the pelvis as the most diagnostic district, in particular the pubic symphysis. Nevertheless, the dramatic increase in values of bias and inaccuracy with increasing age confirms the need for new or revised age estimation methods that better suits the study of the remains of older individuals.

One of the main problems in reconstructing the biological profile of unidentified human remains is the reliability of the methods used. These methods are normally developed on modern identificated human skeletal collections, but human variability can introduce problematic biases when applied on osteological collections from different geografical and cronological contexts. This study test the reliability of selected macroscopic methods for sex determination: the index of sexualization of Acsadi and Nemeskeri, the Phenice method and for the age estimation: the synostosis of cranial sutures (Meindl and Lovejoy), the morphological variations at the pubic symphysis (Suchey and Brooks), the morphological variations at ileum surface (Lovejoy, et al.), the modifications of the sternal end of the fourth rib (Iscan et al.) and the variations of the degree of sacral vertebral body fusion (Belcastro et al.) on a large sample (n.489) of know sex and age from Certosa Cemetery of Bologna and “Colecção Esqueletos Identificados" of Coimbra. Regarding age, for each method was calculated the standard values of bias and inaccuracy. The method of pubic symphysis might be the most reliable for age estimation but we must consider the width of age ranges considered by the method. The values of inaccuracy are over 10 years in individuals older than 50 and 27 years in individuals older than 60. The index of sexualization confirm in more than 99% of cases the known sex and the Phenice method gave good results with the 87% of confirm. The reliability of the tested methods in the two european populations was confirmed, with the pelvis as the most diagnostic district, in particular the pubic symphysis. Nevertheless, the dramatic increase in values of bias and inaccuracy with increasing age confirms the need for new or revised age estimation methods that better suits the study of the remains of older individuals.

The identification of victims involved in mass fatality incidents, as well as the identification of unknown individuals in criminal cases has become an increasingly important issue nowadays. Sex assessment represents a key point in forensic evaluations due to its significance in providing biological identity. Even though the availability of documented skeletal remains to forensic practitioners is a common practice in many countries, in Turkey, contemporary documented skeletal remains are not available for this purpose. For this reason, studies have been focused on living populations. Previous research has shown that modern technologies such as CT scanning present very promising potential in establishing new standards for contemporary populations. Therefore, the main aim of this project was to examine the application of the measurements taken from 3D CT images of the femur in order to assess sex, and to contribute to the establishment of discriminant function equations for the Turkish population for forensic applications. The accuracy and reproducibility of imaging methods in the assessment of the measurements taken from femora are essential when estimating sex. This research also concentrated on determining the accuracy and repeatability of CT measurements, using the femur. Prior to primary data collection, a preliminary study was performed in an effort to test the reliability of the femur measurements. The results of reliability analysis indicated no significant difference between the three observations of each measurement. Thus, the methodology employed in the current study appears reliable and reproducible. In addition, a validation study was conducted to determine the linear measurement accuracy of the 3D volume rendering models derived from a medical CT scanner and the influence of different reconstruction parameters. The differences between measurements obtained from dry bones and their 3D volume rendered models were also evaluated. The results from this study indicated that there were no statistically significant differences between measurements taken from different reconstruction parameters and measurements obtained from CT images and drybones. Using the CT data, volume-rendering function (VR), 3D Curved Multiplanar reconstruction (MPR), and Scout View on OsiriX were employed in order to compare the accuracy and reliability of each rendering method and to determine which technique is optimal for linear measurements. Overall, the measurements taken from the 3D Volume Rendering images had the highest intra-observer reliability when compared to the other two rendering methods. This research study produced data and interpretations that will inform on and improve population specific standards of sex assessment from three-dimensional postcranial osteometric landmarks. Additionally, this research is believed to provide value for a developing discipline of forensic anthropology, and integrate within the existing systems of criminal investigation and disaster victim identification practices in Turkey. A Turkish sample population, consisting of 300 adult hospital patients was examined via the interpretation of CT reconstructed images using the OsiriX software. The 3D reconstructions were then created using the volume-rendering function in OsiriX (v.5.6.). Following the 3D reconstruction, an image of each femur was segmented from the surrounding bones to ensure the correct usage of landmarks as accurately as possible. Thirteen measurements were acquired using a 3D viewer after being located and marked on each CT reconstructed femora. These thirteen anthropometric parameters were measured and analysed by basic descriptive statistics and discriminant analysis methods using the SPSS 21.0 software package. The intra-observer variation was assessed by obtaining the intraclass correlation coefficient in order to evaluate the accuracy of the linear measurements taken. Asymmetry was also tested. The results indicated that an accuracy of 92.3% was acquired from a combination of six of the measurements, and the Femur Vertical Diameter of Neck (FVDN) measurement was found to be the most dimorphic with 88.0% accuracy.

Visual and metric analysis both provide accepted methods for sex determination in humans. Visual ascertainment uses differing morphological traits in males and females to establish sex. Researchers have continually sought accurate methods of sexing long bones when skulls or pelves are absent or fragmented. These long bone elements may not have sexually distinct characteristics, but tend to survive in the field quite well. Metric analysis depends on size dimorphism between males and females to correctly assign sex. Metric methods fail where the sexes overlap or when skeletal elements cannot be assigned to their correct biological population. Under these conditions, visual ascertainment is extremely useful. It relies on descriptive features, not size, to interpret the shape variations between male and female elements. For example, physiological soft tissue variations in the "carrying angle'" of the arm at the humero-radioulnar junction are known to be sexually dimorphic; therefore, the hard tissue features of the distal humerus also should be sexually dimorphic. I observed six distinct visual characteristics of the distal humerus to determine sex in a blind study conducted on 649 individuals sampled from diverse biological populations. In addition to visual assessment, I collected four humeral measurements to determine whether quantitative analysis would be a better indicator of sex than non-metric analysis. I used nonparametric statistical methods to examine· the significance of each morphological feature and its relationship to known sex. All characteristics showed a high association with sex, and the relationships between sex and each characteristic were statistically strong. The final predictive quality of this method was 84% regardless of population; I concluded that my visual method is a dependable sex predictor among diverse populations. Every biological group varied considerably in size dimensions, but exhibited common morphological features of the distal humerus. This confirms that visual techniques provide accurate results regardless of biological affiliation. In many cases, visual assessment was as accurate or more accurate than metric analysis. Therefore, the distal humerus and its unique physical features provide an alternative method to previously used quantitative techniques in the determination of sex.