One of Andrew’s most recent lessons sought to find the reason behind wrinkly fingers. When he announced the hypothesis of the latest study, it immediately took be back to high school. During my senior year, one of my teachers (oddly enough, my philosophy teacher) told me that the skin on our fingers wrinkle because they are beginning to rot. In the search for the true mechanism behind wrinkly fingers, I wanted to investigate this claim made by my teacher.

My high school philosophy teacher told my class that wrinkly fingers are the beginning of the skin rotting, essentially like trench foot (this refers to trench warefare in World War I, after which many men had to have their feet/legs amputated). According to Merriam-Webster, the medical definition of trench foot is “a painful disorder resembling frostbite and resulting from exposure to cold and wet.” This seems to be consistent with my philosophy teacher’s hypothesis, but in order to find out if it was related to wrinkly fingers, I needed to find out more about trench foot to be able to compare it to wrinkly fingers. In an article from the New England Journal of Medicine, one study showed that trench foot could be replicated in rabbits. The study reported that “lesions resembling trench foot have been reproduced in rabbits by shaving the legs and keeping the animals standing for a number of days in a refrigerated chamber on wet mud at a few degrees above freezing couldn’t find any studies related wrinkly fingers to the rotting skin in trench foot.” The article later states that feet become “swollen and blistered” and look “cadaveric in color.” This didn’t seem to correlate with wrinkly fingers, as wrinkly fingers don’t develop any legions on the skin, don’t get blisters, and certainly don’t swell up. In fact, the skin on your fingers seems to do the opposite of swell, but rather suck inside itself. After finding few other results, I decided to do some speculating of my own and figure out why the heck my philosophy teacher wanted to relate wrinkly fingers to a cold, wet, rotting foot.

I decided to take a step back and think about what I could be missing, and in the same article from the New England Journal of Medicine, I made a discovery of my own. Trench foot was often mentioned hand-in-hand with the term immersion foot. According to Merriam-Webster, immersion foot is “a painful condition of the feet marked by inflammation and stabbing pain and followed by discoloration, swelling, ulcers, and numbness due to prolonged exposure to moist cold usually without actual freezing.” Now, if immersing (hence the term “immersion foot”) one’s foot in cold water causes damage, couldn’t immersing one’s foot in warm water cause just as much damage?

Apparently, yes. After doing some research, I found that warm water immersion foot was studied in U.S. Soldiers during the Vietnam War. Another article from The Lancet , a medical journal from the United Kingdom, stated that warm water immersion foot “is a syndrome characterized by painful, white, wrinkled soles.” My results suddenly became a little bit more clear. Wrinkly fingers could be directly related to the effects of warm water foot immersion, not trench foot.

So, why do the two often get so confused? My theory is that it has something to do with the smell. Think of it like this. Warm water foot immersion is more like putting a band-aid around your finger for a long time, and trench foot is more like getting a bad case of frostbite on your fingers. When you take off the bandage, your fingers (and the bandage) smell pretty bad. When you get frostbite and the flesh on your finger starts to die, it can smell pretty bad too.

When I asked Andrew why there weren’t more studies or compiled works on the cause behind wrinkly fingers, he said it was because there were more pressing issues at hand. Personally, I think that everyone should know whether there fingers are going to rot or not.