Time Since Injury

I bet if you’ve watched crime tv shows and movies, or read lots of crime novels you know what “time since death” is. It’s the time between the body’s death and when the body was found. It can be abbreviated TSD. This is a popular thing at the University of Tennessee (UT), where the postmortem interval (PI), aka TSD, is estimated using techniques and methods to determine that time interval based on rate of decomposition, temperature, environment (arid, moist) insect activity, possibly a particular type of injury that caused death could have contributed to the PI, etc. Everything counts. BU didn’t have body farm like UT does for these types of experiments, so I never dealt with decomposing bodies, although it’s super interesting; one that I considered for my thesis work in the beginning stages of thesis prep.

Writing a thesis: I think it’s a very silly thing to just pick a topic you like and then report on it when it comes to a scientific experiment. It was like pick something FA that you like at random. Then you can write a thesis on it. I know that there are a lot of topics to be explored and I knew what they were but it’s not that easy. I would feel more comfortable doing an experiment on or studying something that needs to be experimented on or studied, something at hand. It’s like creating something out of nothing just to analyze it sometimes, like trying too hard, I don’t like that feeling. If I wanted to study decomposition, I would need test subjects, a location that allows me to let something rot away, and lots of information about the environment. As you can imagine a decomposing body in Boston takes a lot longer to reach skeletonization than it does in Tennessee, in general. Why? Mainly because of the higher temperatures and the higher level of humidity in Tennessee, likely leading to an increased number of insects feeding. So say you were going to use pigs to do your study: pigs are said to decompose most similarly to humans than other species. Two reasons that I know of is one, because they don’t have fur so the skin exposure is similar, and two, the types of decomposition chemicals and chemical counts are more similar than compared with other animals or other species. The scenario would be: I’m buying a pig for my experiment. (Interesting http://venus.uvic.ca/tag/forensic-research/) I’ve read that it costs $1 per pound for a pig carcass and a pig can weigh like 200 pounds. Ok, so I get a little one that’s only 100 pounds (I don’t know if that’s accurate). Well I can’t just have one pig to watch decompose because I’ll have nothing to compare it to and no one is going to take a single pig decomp analysis as seriously as multiple pigs. So I’d need to buy multiple pigs for the experiment. And then I go to hell for it. Just kidding.. but really.. I’m not into using living things for experimentation because I think that’s cruel in nearly all cases, but these experimental pigs are most likely coming from slaughter houses and they’re already dead when I get them, so it’s ok. NOT! Possibly even a worse concept, but who am I to say? Would I be inadvertently supporting slaughter houses? Too much to think about so no thanks, this pig idea and decomp idea is out. I’m not about to join any revolts to defend this matter, but it’s just not my cup of tea plus holy crap that’s expensive and there was no funding for our thesis work.

Needless to say, decomp wasn’t entirely what I was interested in, but it certainly was on the top of my mind because it’s an appealing and popular subject. Well I didn’t get into FA because it was popular. I didn’t watch Bones one day and say, “oh cool, let me spend $80,000 to go to school for that even though it’s extremely unlikely that I will get a job pertaining to that field”. I liked anatomy, I liked history, I liked chemistry, and then after taking some courses I LOVE anthropology. I like the nitty gritty experimentation and reporting aspect of scientific research. (Call me a geek but) I can read forensic science journals all day about other people’s experiments/studies but until I get in there and see what’s up for myself I can’t just trust everything I see or read. Next, I reflected on the commonly over-asked question “what do you want to be when you grow up?” When I was younger I said physical therapist, linguist, or archaeologist. So I’m thinking what can I get out of that so I don’t get bored with this thesis project that will take me an estimated 9 months?

Ok healing in bone. Oo xrays.. oo and histology.. cool technology! So I proposed the idea to analyze histological slides of bone at different stages of healing to see what it looks like and identify common indicators. Then the director of the program asked how I would feel about looking at the histology of age in bone? She had some monkeys almost ready for experimentation (already dead, not killed for experimentation). Well, that didn’t work out because the monkeys had Hepatitis and couldn’t be used after all. Then I thought Boston Medical Center must have histology slides from living people; why do they have to be dead? That didn’t work out either; but I still believe it could. Just like FAs can make conclusions about bony stuff from CT scans and radiographs taken on living people over time to compare. If there are methods developed for analyzing living people with these technologies then the sample quantity will largely increase. Plus nothing would have to die to make a good scientific conclusion or ten. So I’m still on healing in bone. I think it’s fascinating and I think it can tell a lot regarding the reconstruction of events surrounding death, even if the injury didn’t directly cause death, and to make a positive identification. Dr. Prince suggested using the Civil War Collection at the Armed Forces Institute of Pathology since those specimens have sustained injury(ies). I got in contact with Dr. Damann and he suggested to read a relatively recent article by Barbian and Sledzik to prepare myself and get some ideas. My proposal was to analyze healing in bone using eyesight only with no magnification, over time, using Barbian and Sledzik’s method but slightly modified. I ended up modifying their method a lot but that’s beside the point.

Why did I want to look at the appearance of healing bone over time? I wanted to be able to figure out when the person was injured before they died. I deemed this “time since injury” and I’ll abbreviate it TSI. I’m so creative, I know haha.. I definitely learned how to deal with when a project plan is altered many times and try to stay on track for the original goal. It also didn’t help that I wrote to my advisors for about 4 months before I got a response. It would have been nice to have a little more guidance but whatever I only grew about 200 gray hairs and had minor anxiety attacks over it.

My presentation at NEAA: After establishing my selection, I was able to clearly display my staging system using a photo and description for each stage of each response. I had a laser pointer to point out the details. I can’t show the photos because it’s confidential and personal and I signed a paper saying I wouldn’t. Following the photos, there was a results table showing the week in which the response was first and last observed, and then there were several slides of charts showing trends. By analyzing when the responses were first and last observed I was able to make a few conclusions such as response number 1 was not observed after 4 weeks. So if you found a bone at a crime scene with that response at that stage you can use this result to help determine that death happened within the first 4 weeks after injury. The first set showed the number of responses observed over time, the next set showed the score over time (Barbian and Sledzik’s method), and the last set showed my stages over time. What I got from this was a line graph that showed a trend for when each response was most commonly observed and at what stage. The line graph helps visualize the overall objectives of the study.

This stage of this response is most likely observed 4 weeks after death.

My major conclusions were that unlike Barbian and Sledzik the score of responses did not increase over time, some time frames for when the responses are observed were established, and most importantly the observation that infection mimics some of these targeted responses. Two examples of how this experiment relates to everyday life is one, a common type of injury amongst a group of people and time of injury before death (TSI) may indicate a mass fatality of some sort which can give the FA clues about what happened (humanitarian/human rights efforts), and comparing antemortem and postmortem radiographs or medical records may assist in a positive identification; meaning if there was a bone found and we estimated it was injured 5 weeks before, we can go to the local hospital, look for similar injuries at that time, then use that information in addition to other information to work towards making a positive identification of the victim.

Further directions: statistical comparison between groups, use radiographs or other technology, focus on the combination of responses over certain time using my scoring method, and to do this with a sample without a high rate of infection.

After my presentation I think there was one other person but I have no recollection of what went on for 15 minutes proceeding my presentation haha. Or it’s just been too long to remember what it was about. At the end the mediator told me that her husband had some questions/comments about my presentation. He’s an MD! He brought up the idea/issue that the victims might not have died from injuries and infection but from organ problems. It’s an interesting concept that the cause of death would contribute to the TSI calculation, as would numerous other factors. But like I mentioned earlier, the more sample specimens the better to get a general understanding of what happens. It’s not going to be 100% of the time this is what bone healing looks like 3 weeks after injury. So I responded to him that I think it’s a great inquiry and I would definitely love to pursue this topic further, but my experiment couldn’t get too deep into that plus the collection I observed had a limited amount of information. My approach was to have a specific and narrow focus so that extraneous factors wouldn’t interrupt or complicate my study. That wasn’t entirely avoided, but good enough.

The next day, Saturday, I went back down to BSU to see some posters and hear some more presentations. They were undergraduate presentations on ethnographic work basically and there were only a few posters. One poster was interesting. What is the stigma or a rape kit and this feminist presenter was trying to convey that negative implications come from using rape kits and rape kit results. One outcome could be that the results are positive and the woman is deemed victimized, the results are positive and people still don’t believe the woman, they think she is lying, the results are negative and the woman is labeled as a liar and no one believes her, the results are negative or positive and the woman didn’t want her personal information to be “out there” but if the case is presented to a jury then the woman’s very personal business is sort of plastered all over the wall for everyone to see. She did a good job standing her ground. I asked her a bunch of questions because she has statistics on her poster that she got from a few different places. It was interesting. I asked her if she thought that rape kit testing was overall a good thing and beneficial and she said no and supported her answer by providing facts that lead her to believe that the kits don’t work. I’m not saying I believe her but she did a good job presenting her argument.

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