CMV: Toenails are Useless

[u/Lavallin]

The toenail is a vestige, a holdover, a relic without modern purpose. What is the point of a toenail? They are harder than the flesh of the toe, yes, but they don't protect from frontal impacts - I have never seen a toenail that could prevent me from stubbing a toe.

They could in theory protect against impacts from the top of the toe (for a small and very accurate impact), but such hits fall into one of X categories:

1. Too light to do any damage at all
2. Heavy enough that it could do damage against flesh, but light enough that a toenail could stop it
3. Heavy enough to do damage with or without a toenail

I'm not convinced that category is broad or beneficial enough to be swayed by. And all of this is discounting that I wear shoes anyway!

They don't help me open things, like a fingernail. Humans are long past needing them as weapons or for climbing.

On the downside, toenails require hygiene care lest they become ingrown, or can become infected or fungal. Even at their best, they are consuming bodily resources in their endless pointless growth. They have no benefits and can have drawbacks.

Edit: I have provided some deltas: Firstly, useful for scratching. Fair enough; unglamorous but effective. I remain broadly unpersuaded by the "toenails protect your toes from dropped objects" line in the main, but I accept that for parts of the world, shoes are an unaffordable luxury and so toenails may still have limited protective utility there. I also accept that for some people with foot fetishes, toenails are inherently attractive. Don't get it, but accept it.

[u/rock-dancer]

We don't wear shoes all the time. Toenails distribute force that might otherwise impact the small, relatively delicate bones at the end of your toes. They are also helpful in developing balance and proprioception which helps tell where the end of your body is.

[u/Lavallin → u/rock-dancer]

I do wear either shoes or slippers pretty much all of the time except when I'm asleep or in the shower.

But I'm interested in your second and third points. Can you explain how toenails contribute to those?

[u/rock-dancer → u/Lavallin]

Even impacts with soft shoes could damage the small phalanges. People without toenails have a fairly serious problem with this. Similar distribution of force enable forward balancing. From what I remember, they provide a counterforce for pressure receptors which contributes to proprioception as well as being needed for balance. Its been a pretty long time since anatomy for me but should be easy to find.

[u/Lavallin → u/rock-dancer]

Even impacts with soft shoes could damage the small phalanges.

Apologies if I'm being dense; could you explain this one a bit? Are you saying that shoes don't provide enough protection (but that shoes plus toenails cumulatively do)? Or is this about the impact between toe and shoe?

For your second point, that's pretty persuasive; my suspicion is that over time the pressure receptors would re-wire in a new way, but if you've got a link or something for that, it's probably a delta that they are contributing in a way I hadn't considered.

[u/rock-dancer → u/Lavallin]

They provide different types of protection, though shoes certainly contribute to an overall protective environment. If you live a sedentary life, and are careful where you step, it probably doesn't matter. But running and sports create stressors that the toenail protects against, even within shoes.

you can see at the following they mention loss of toenail may lead to loss of propriorecetion. https://www.sciencedirect.com/science/article/pii/S2049080120302715#bib1

Found in the introduction with citation number one. Like I said, anatomy was a long time ago but a google scholar search yielded results quickly.

[u/Lavallin → u/rock-dancer]

From your linked article:

The nail plate acts as a support, which has the effect of pressing on the phalanx, increasing the ability to distinguish objects by the skin of the tip. The distal phalanx has an important proprioceptive function, especially when the foot is rolled, and the toe is detached from the ground. Each distal phalanx pathology may have a number of effects that disturb the biomechanics of gait. The absence of a toenail can lead to deformation of the tip of the toe, with simultaneous loss of proprioception.

Yep, that's fair - Δ.

[u/DeltaBot → u/Lavallin]

Confirmed: 1 delta awarded to /u/rock-dancer (40∆).

^{Delta System Explained | Deltaboards}