Why does it hurt so much to stub your toe?

August 4, 2012 10:02 AM

Clinical assistant professor of kinesiology Chris Geiser at Marquette University explains why it hurts so damn much when you stub your toe.
posted by escabeche (29 comments total)

I broke a toe running up my parents' deck stairs - my mother had inexplicably placed a large rock on them and it was right after the transition from very bright sunlight to shade. You know that feeling of sharp pain when you stub a toe, but it fades very quickly? When you break a toe IT DOESN'T FADE. So if you don't like that feeling, don't kick rocks.
posted by jimmythefish at 10:10 AM on August 4, 2012

How about why stubbing is so much more painful when your hands/feet are cold?
posted by DU at 10:16 AM on August 4, 2012

It has been suggested that individuals who received lots of sensory information from their toes were less likely to strike them, creating an evolutionary advantage for people blessed with this type of sensory information. So there are many components to this amazingly painful question.

Can't decide if our genes are super hoarders or just ridiculously ignorant about modern medicine. And why is this stuff coded to my reptilian brain and yet I can't remember the name of the person I met five minutes ago?
posted by Foci for Analysis at 10:19 AM on August 4, 2012 [1 favorite]

It has been suggested that individuals who received lots of sensory information from their toes were less likely to strike them, creating an evolutionary advantage for people blessed with this type of sensory information.

Fun fact: The part of the brain that receives sensory information from the toes is directly adjacent to the bit that receives sensory information from the genitals.

Word of advice: Avoid stubbing your genitals.
posted by Sys Rq at 10:33 AM on August 4, 2012 [21 favorites]

How about why stubbing is so much more painful when your hands/feet are cold?

You feet just aren't cold enough. Try getting them nice and frostbitten so they lose all feeling.
posted by Sys Rq at 10:34 AM on August 4, 2012

This question has been simmering on the back burner of my mind my entire life. I feel better now.
posted by scose at 10:41 AM on August 4, 2012 [1 favorite]

In training for night movement, I found out that I can feel blades of grass through the soles of my boots, and that I can hear better with my mouth wide open.

I need to know why it hurst more (when you stub your toe) if you don't scream, and why certain words make it feel better. I can't wait to hit Mr Obvious with that stuff.
posted by mule98J at 11:05 AM on August 4, 2012 [6 favorites]

Every time I stub my toe I realize I couldnt hold out for one minute with a truly motivated interrogator.
posted by villanelles at dawn at 11:14 AM on August 4, 2012 [16 favorites]

I need to know why it hurst more (when you stub your toe) if you don't scream, and why certain words make it feel better. I can't wait to hit Mr Obvious with that stuff.

Swearing can help relieve pain, study claims. The actual paper is here.
posted by jquinby at 11:17 AM on August 4, 2012 [16 favorites]

I need to know why it hurst more (when you stub your toe) if you don't scream, and why certain words make it feel better.

I recently stubbed and broke a toe. My cat is going through a very nervous period thanks to renovation work next door, and hates loud noises with more than her ususal passion. So, I tried. I hopped carefully about, softly breathing "oh oh oh", spinning on my good foot, throwing head around. The pain just climbed and climbed and climbed. It only started back down when I caved and informed the doorjam that it was a goddamned fucking asshole.
posted by likeso at 11:17 AM on August 4, 2012 [18 favorites]

So, our toes are like a dog's nose?
posted by zzazazz at 11:25 AM on August 4, 2012

And why is this stuff coded to my reptilian brain and yet I can't remember the name of the person I met five minutes ago?

Because that person isn't going to kill you.

At least, not that your reptilian brain knows of.
posted by Etrigan at 11:28 AM on August 4, 2012

Fun fact: The part of the brain that receives sensory information from the toes is directly adjacent to the bit that receives sensory information from the genitals.

Word of advice: Avoid stubbing your genitals.
posted by Sys Rq

Excellent thinking, Sys Rq.

I think it's quite likely that any mutation which caused greater pain sensitivity in the genitals would also bump up the pain sensitivity of the toes as a side effect, and that more sensitivity in the toes would therefore be promoted by any selective advantage conferred by greater pain sensitivity of the genitals, all the more so because of the imprecision and blurriness of the way the developing brain hooks itself up as bundles of nerve fibers grow along chemical gradients to reach their targets, so that you would expect mixed areas at the common borders of adjacent sensory domains in the brain pertaining to separated parts of the body, given that there's no difference in tissue types to keep them apart.

In some ways the severe pain that can come from my toes isn't all that immediately useful to me because it takes a significant fraction of a second to arrive after I realize I've stubbed them, just enough time to stop moving and think 'Oh Crap!' before it really hits.
posted by jamjam at 11:39 AM on August 4, 2012

Thanks! Definitely had wondered this from time to time; the amount of pain caused by a stubbed toe has always seemed way out of proportion compared to the amount of damage that's actually been caused, but this explanation makes some sense even if it does seem a bit post hoc.

Now can someone explain knuckle cracking? What the hell is going on there and why do I feel twitchy if one of my knuckles needs popping?
posted by Scientist at 12:03 PM on August 4, 2012

Sys Rq's comment is much more informative than the OP, which is just a mashup of obvious kinesiology and speculative EP.
posted by localroger at 12:21 PM on August 4, 2012

Now can someone explain knuckle cracking? What the hell is going on there and why do I feel twitchy if one of my knuckles needs popping?

When you stretch the relevant joint, the change of pressure causes bubbles of dissolved gas (I think usually nitrogen) to come out of solution and then pop in the liquid of the joint. You're hearing those microbubbles pop.

Not sure why it feels good to do it.
posted by kavasa at 1:04 PM on August 4, 2012 [1 favorite]

This is timely.

I stubbed my toe on an ill placed box of books while trying to get a cat off the top of the bi-fold closet doors at 5am this morning. My toe is swollen and purple. I'm not sure the swearing did anything to mitigate the pain.
posted by The Hamms Bear at 1:38 PM on August 4, 2012

I thought I'd broken my toe playing soccer recently. The Hamms Bear, you may have a subungual hematoma (blood pooled under the nail causing pain by pressure buildup). I got my nail pierced by a doctor to let the blood out, but my friend tells me he just burned a hole in his with a heated paperclip. My toe had been almost unwalkably painful for three days and was pretty much back to a mild bruise the day after I got this done, I highly recommend it.
posted by jacalata at 2:18 PM on August 4, 2012 [1 favorite]

> The part of the brain that receives sensory information from the toes is directly adjacent to the bit that receives sensory information from the genitals.

Sys Rq is strongly advised to not give Mrs. Marcelus a foot massage.
posted by bukvich at 3:32 PM on August 4, 2012 [1 favorite]

I stubbed my genitals once... 'Cause I can. It's okay, go ahead and feel jealous.
posted by ashbury at 4:56 PM on August 4, 2012

I took anatomy this summer and was really excited to find out that our feet carry really wonderful evidence of our chimp-like ancestor. Humans are the only bipedal modern apes, and part of becoming bipedal was losing our opposable big toe. Our big toe gradually moved in line with our other toes, and stopped being able to move independently, probably because having a giant thumb sticking out of our feet would make running long distances efficiently difficult (this is why primates that brachiate, like gibbons, have reduced their thumbs to basically stubs). But - the musculature controlling our big toe is practically the same as the musculature controlling our thumb. Because evolution just tinkers, it's easier to keep control of the toe the same as it was when it was much more awesome than to evolve new and potentially more efficient muscle control.
posted by ChuraChura at 5:40 PM on August 4, 2012 [1 favorite]

It's actually all purple and swollen right behind the nail (on the "this little piggy had none" toe) which is great because I'm a big baby who won't be puncturing anything with a red hot paper clip unless I'm stranded on a deserted island and maybe not even then, thank you very much.
posted by The Hamms Bear at 6:27 PM on August 4, 2012 [1 favorite]

Fwiw, anecdotal evidence suggests that when you stub your toe into something, you _may_ avoid most the pain by simply telling yourself immediately that 1) "i realize that I've hurt myself", and 2) "Please don't hurt, I'll take care of it". It doesn't seem to work if you don't believe it; so - ymmv....
posted by onesidys at 9:45 PM on August 4, 2012

posted by jquinby: "The actual paper is here."

I knew it! I just fucking knew it.
posted by mule98J at 10:31 PM on August 4, 2012

Um... I can certainly move my big toe independently of the others. Can't really do that with any other of my toes, but my big toes are certainly free to do their own things.
posted by Navelgazer at 11:12 PM on August 4, 2012

And upon thinking this over and experimenting, can do limited independent movement with the little toe as well. But not the three in the center.
posted by Navelgazer at 11:14 PM on August 4, 2012

Fun fact: The part of the brain that receives sensory information from the toes is directly adjacent to the bit that receives sensory information from the genitals.

And that is why if you have a foot amputated, you might experience orgasms in your phantom foot.
posted by homunculus at 12:07 AM on August 5, 2012

Product of a little pseudo-ego Googling there, homunculus? Pseudo-ego Googling never nets me anything that cool.
posted by cgc373 at 12:15 AM on August 5, 2012 [2 favorites]

Right, because we still have the muscles that allow our big toe to oppose, but our toes have changed shape and we have a band of connective tissue holding all our metatarsal bones together, not just the metatarsals of your four not-big toes. That's why we can't use our feet as extra hands.
posted by ChuraChura at 3:47 AM on August 5, 2012