Body mass estimation using bone micro- and macro-structure: a practical approach using CT imaging and computer analysis

When developing the biological profile, forensic anthropologists routinely estimate sex, age, ancestry, and stature. However, body mass is generally not included in the biological profile due to the lack of methods for accurately estimating body mass from skeletal remains, especially for obese individuals. As the prevalence of obesity increases so will the chances of encountering obese individuals in medicolegal death investigations. Therefore, the estimation of body mass or the body mass index (BMI) category may provide greater details for matching unknown and missing persons profiles than other biological components. In addition, obesity is known to affect the accuracy of methods for estimating age at death and facial approximations used to assist in the identification of unknown individuals. Thus, the ability to establish if an individual was obese at the time of death will be a valuable addition to the biological profile of unknown skeletal remains in medicolegal death investigations, and therefore of great importance to the criminal justice system. The purpose of the proposed research is to enhance medicolegal death investigations of unidentified skeletonized individuals by developing a novel method for accurate and reliable estimation of body mass and/or BMI categories with measured uncertainty from human skeletal remains and a user-friendly cross-platform software package (Forensic Body Mass Estimation Toolkit) that can be used by forensic anthropologists working in the United States. The project involves combining joint size, trabecular bone structure, diaphyseal cross-sectional properties, and whole bone shape focusing on differences associated with excess adiposity on weight bearing bones of the skeleton. The approach of the proposed study will either demonstrate a reliable and accurate relationship between skeletal features and body mass / BMI or demonstrate that no such relationship exists and that radically different approaches (non-skeletal) to body mass estimation will be required. This is a collaborative study that brings together three research groups with various complementary resources and skill sets. Texas State University has the equipment and skeletal sample necessary, and importantly, the technical knowledge required to scan, reconstruct, and archive such an ambitious sample of human skeletons. Researchers at Johns Hopkins University have the image processing and trabecular bone analysis software in place to carry out the analysis of the data generated by Texas State University. Neither group can carry out the research individually, but the collaboration of researchers at these two institutions ensures the success of the proposed project. Note: This project contains a research and/or development component, as defined in applicable law, and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14). CA/NCF