Normally, our nail beds are permanently covered by fingernails. Why are there any nerves under them?
After an unfortunate incident involving a sharp kitchen knife last weekend, I’ve discovered that having a patch of suddenly bare nail bed is uniquely uncomfortable. The cut was largely parallel to the surface of the fingernail, starting about halfway up the nail and exiting at the end of the nail, and resulted in a roughly 1/4" diameter patch of missing nail.
Just a stray air current on it was miserable, never mind the manipulations involved with cleaning the wound area and bandaging it. I’ve had all sorts of scrapes and cuts on my body, and don’t recall any that would hurt and sting so intensely if gently blown on that I want to hack the remaining part off, figuring an amputation would probably hurt less.
Normally, I have a fairly high pain tolerance - I’ve had doctors remark that most people with a back injury as bad as mine was (since fixed surgically) would be curled up in a little ball and unable to walk, but I was carrying on as if little was wrong and saying “My back kinda hurts.” But the pain caused by a piece of finger nail being sliced off? Utter agony. I can understand the whole bamboo shoots under the nails thing now.
I did that a few years ago on a paper trimmer in a print shop. Shaved half my thumbnail off.
When i turned around to tell my partner “I cut half my fingernail off”, she did the whole “poor baby broke a fingernail” sarcastic thing. Until she looked at it…and almost face planted int he middle of the shop.
And yes, it hurt like hell and I am another one with a very high pain tolerance.
There are huge amounts of nerve endings just below the epidermis all over your hands. Removing a nail is like shaving off some skin to the raw part underneath. The part under the nail bed isn’t really any different than any other part of your skin. Just a couple of days ago, I scraped off a piece of skin on the side of my finger, and when I washed it under water as warm as what I usually use, it felt like a hot poker.
Evolutionarily speaking, if I had to guess, I’d say lots of nerves under the fingernails is a side effect of lots of nerves on the rest of the finger, something harmless enough that evolution hasn’t gotten around to getting rid of. Though it’s also possible that they nerves pick up a lot of information about the stresses on the end of the fingernail, and that’s we use that information more than we realize in handling things.
I once managed to drive a wood splinter under my thumbnail, past the quick. The pain was severe, the pain of removing the splinter was intense. The doctor pumped my thumb so full of local anesthetic that it looked like my big toe, it was literally oozing back out of the numerous injection sites. Even that wasn’t enough to keep it from hurting, a nurse had to hold my hand down while the doctor jabbed hemostats up under the thumbnail to pull the splinter out. I had a rasied line of discoloration growing out of that nail for a long time.
Pre-dentistry, knowing what tooth is going bad was a matter of life and death. If it can be pulled out in time you may save yourself from a potentially fatal infection.
Fingernails might be the same thing. An infection under the fingernail can quickly get out of control. Signaling it with intense pain may have been natural selection’s only option in making us quickly tend to it.
I vote for this one. I use my nails for lots of things and if there were no nerves to give feedback on what the nail is doing, it would be a lot more clumsy.
I did find some medical articles on the treatment of nail bed injuries that mention how the sense of touch in the affected finger will be diminished until the new nail grows in - seems that the nail provides a sort of back-pressure to the nerves in the fingertip.
I recommend the application of liquid bandage, available at any drugstore. There will be a moment of sharp, stabbing pain as it is applied, but once it covers the entire wound you will no longer feel a thing, and you will have the use of that finger back.
Liquid Bandage? Oh, you’re a special kind of sadist.
I’ve used that stuff before on other injuries, and for me, at least, it’s not a moment of pain, but several minutes of searing pain so bad that I want to gnaw off the injured part.
This whole thread is making me cringe. I learned very quickly to put knives and forks (the tines are brutal) business-end down in the silverware holder in my dish drying rack. The bamboo-shoots-under-the-fingernail torture would be brutal, I’m sure.
I’ve used it on open wounds where a bandage couldn’t be applied because the continued work to be done would take it off and dirt would get under it anyway. It did a decent job of sealing the wound from dirt and was worth every bit of momentary pain which didn’t last long.
