Sense of Humerus

Emily Streetman: Anthropology Doctoral Student


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My experience as a JPAC visiting scientist

In June 2012, I visited the Joint POW/MIA Accounting Command Central Identification Laboratory (JPAC/CIL) at Hickam Joint Base in Honolulu, Hawaii. Despite the lengthy name, you might guess from the “POW/MIA” part of it that their mission is to identify and bring home all unaccounted-for American military servicemembers. It’s the single largest employer of forensic anthropologists in the country, trailed by the New York City Office of the Medical Examiner. You might not know that there are thousands of unaccounted-for American service members from conflicts in the 20th century. What you should know is that the team at JPAC works daily to find Americans’ remains, identify them, and send them home to family members who have lived in limbo for decades.

Photo by Flickr user Beverly & Pack

As a visiting scientist, I was there to work on a specific project. In this case, a two-pronged look at the patella (kneecap) as a uniquely identifying bone. Previous research* by Dr. Carl N. Stephan, the JPAC/CIL anthropologist who sponsored my visit, has looked at the clavicle in a similar way. The clavicle and cervical vertebrae 3-7 is a great locus to start, because all service members had to be screened for tuberculosis in the mid-20th century, so archives are filled with radiographic (x-ray) and photo-fleuroscopic films waiting to be matched to unidentified remains.

The first part of the patella research continues a series of validation studies that show how good forensic anthropologists are at determining a match – does this Person’s medical record match the John Doe in front of you?

The second part is more quantitative. Following Stephan et al. 2011a, we used a NextEngine scanner (3D-imager) to digitize the patella, processed the surface images with Meshlab, derived 15 outlines from each scan, generated Elliptical Fourier coefficients for each using Shape v.1.3.We compared these outlines with outlines derived from radiographs of the same patella in situ and analyzed the results with new code in R. (For a post on my experiences as a novice coding in R, click here.) . The results of both parts of the study have been submitted to the 2013 Annual Meeting of the American Academy of Forensic Sciences.

Overall, I had a great time at JPAC/CIL. Being on a military base was a new experience for me, and this was really only the second lab of which I’ve gotten to see the inner workings. Many of the employees from the CIL participate in the Scientific Working Group for Forensic Anthropology (SWGANTH) along with my advisor, Todd Fenton, so there’s a lot of overlap in the way we do things. However, in addition to lab work, CIL employees also go into the field (mostly in Southeast Asia, but with some European missions) to do recoveries. It’s this that seems to make or break newbies – so I’m interested in getting a taste of it by applying to the Forensic Science Academy, a semester-long program offered by JPAC/CIL that includes a 30-day field mission to Vietnam. Wish me luck!

 

*Stephan CN, Emanovsky PD, and Tyrrell AJ. 2011a. The use of clavicle boundary outlines to identify skeletal remains of US personnel recovered from past conflicts: results of initial tests. In: Lestrell PE, editor. Proceedings of the First International Symposium of Biological Shape Analysis. 2009 Jun 3–5. Tsukuba, Ibaraki, Japan. Singapore: World Scientific Publishing.

Stephan CN, Winburn AP, Christensen AF, and Tyrrell AJ. 2011b. Skeletal Identification by Radiographic Comparison: Blind Tests of a Morphoscopic Method Using Antemortem Chest Radiographs. Journal of Forensic Sciences 56:320–332.
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