The 89th Annual Meeting of the American Association of Physical Anthropologists (2020)

Sacral Traits as Age Indicators: A Validation Study


Anthropology, Texas State University

April 16, 2020 , Platinum Ballroom Add to calendar

Wide prediction intervals in adult age estimation have fueled continuous research into potential age indicators and methods to narrow the predictive range. Several methods have been proposed and a new program—Transition Analysis 3 (TA3)—is currently being developed. TA3 uses indicators of several elements based on experienced observations (Ousley et al., 2019). The sacrum is a point of interest in TA3, as well as Passalacqua’s (2009) method. To assess the use of the sacrum for adult age estimation, the seven traits from Passalacqua (S2/S3 fusion, S1/S2 fusion, microporosity, macroporosity, surface changes, apical changes, and S1 ring fusion) and the three dichotomized traits described in the proposed TA3 manual (S1 margin shape, S1/S2 fusion, sacral elbow) were scored preliminarily on 20 individuals from the Texas State Donated Skeletal Collection (TXSTDSC) ranging in age from 18-91 years. Results show that 85% of individuals scored using the Passalacqua coding system fall within the given ranges, 52% of those falling within the narrower 68% range. As TA3 does not have a given age range for each trait, the three features’ scores were assessed using a Pearson correlation regression analysis. S1 Margin Shape shows a significant correlation to age at death (r=.6887, p<.001) as does S1/S2 Vertebral Fusion (r=.6523, p<.01). No individuals had the presence of a sacral elbow, indicating a lack of significance in the sample. These results indicate that scoring age-related sacral traits may be a useful addition to age estimation methods for a modern population.

Slides/Poster (pdf)