Review ArticleForensic age estimation in human skeletal remains: Current concepts and future directions
Introduction
Forensic anthropology is a discipline that is continually evolving and expanding. Not only does the role of the forensic anthropologist include the traditional study of human skeletal remains for the purpose of identification (e.g. building a biological profile, trauma analysis, facial reconstruction), but it now also frequently involves identifying the living (e.g. ascertaining whether a person has reached the age of criminal responsibility). The expansion of the discipline, combined with rapidly improving technology, has seen a real increase in the development of new, and refinement of existing, methods. The historical development, current state, and future direction of the discipline was recently comprehensively reviewed by Komar and Buikstra [1].
Forensic anthropologists generally apply their expertise to medicolegal investigations, from single homicide cases, through to mass death scenarios resulting from violent activities (e.g. 9/11 – [2]; Bali bombing – [3]; war crimes – [4]) and natural disasters (south Asian tsunami – [5]). When unknown remains are referred to the forensic investigator, one of the first stages of the identification process (after ascertaining that the remains are actually human and of forensic relevance) involves formulating the biological profile (osteobiography); sex, age, ethnicity and stature. With each of these factors a range of considerations ultimately determine choice of method and accuracy. The present paper briefly reviews a selection of the principal methods used for one aspect of the identification process, the estimation of personal age in human skeletal remains, and discusses some of the factors that underlie how an appropriate technique is selected.
Section snippets
Selecting an appropriate method
Age estimation depends in part on the skeletal elements available for analysis; different bones are inherently more resilient than other to damaging taphonomic processes, resulting in some bias in preservation [6], [7]. The nature of the death(s) being investigated also influences this process; e.g. a high velocity impact usually results in increased fragmentation [8]. Subsequent considerations are typically related to the actual method(s), which as outlined by Ritz-Timme et al. [9], should
Age estimation – juveniles
It is well-documented that age estimation is usually most accurate in individuals still growing. In mature individuals, most standards generally rely on the highly variable deterioration of morphological markers (e.g. pubic symphysis; sacro-iliac joint; sternal rib ends) that are more influenced by environmental factors, as opposed to the more predictable and well-documented developmental markers characteristic of the juvenile skeleton (e.g. dental development; skeletal growth and maturation)
Age estimation – adults
Age estimation in adults, in the absence of key developmental markers, depends on the more highly variable degeneration of bones. This is further complicated by the fact that individualistic factors (e.g. lifestyle, health and nutrition) can influence skeletal remodeling throughout life, introducing an extra source of bias into the final assessment. Different parts of the skeleton can thus ‘age’ at different rates, both between and within individuals. In their analysis of the Branch Davidian
So what does the future hold?
Anthropologists interested in the skeleton have traditionally relied on the direct examination of physical remains as a primary source of research data. As repositories of documented skeletons (both juvenile and adult) are becoming increasingly rare, and considering that many of the extant collections comprise individuals dating from historic periods, alternative data for modern populations must be found. Clinical images, such as radiographs, computed tomography scans and magnetic resonance
Official disclaimer
The author discloses no financial relationship with commercial entities.
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