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NanoByte
11-13-1999, 12:34 AM
How do fingernails and toenails, after being damaged to an irregular distal periphery, know to cause more growth at their shortened locations than at their less-damaged locations, so that they soon again have roughly a uniform length across their width?

Ray

11-13-1999, 01:02 AM
They don't.

The longer parts of the nail wear down while the short sections don't. The apparent result is that the short sections grow faster, but this is an illusion.

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Sue from El Paso

Experience is what you get when you didn't get what you wanted.

NanoByte
11-13-1999, 01:22 AM
Observation certainly proves that what you say is untrue. That is generally my main problem with physicians. Normal nails not damaged grow until they are cut/damaged. If this does not occur, the damaged part catches up in length to the undamaged part. State your authority. . .or is this answer of yours based on watching nails grow? Is this another old physicians' tale / shamans' legend?

Ray (Ouch! Cut those things!)

handy
11-13-1999, 10:16 AM
NanoByte, not mine. Mine grow as the guy said.

Nails are inert horn. The base doesn't know what the tip is doing anymore than your scalp knows what your hair tips are doing.

Whammo
11-13-1999, 10:26 AM
Nano... do you have a link to a medical journal or something that can substantiate your theory?

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"Boy, wouldja get a load of the cloaca on that one"? -Cecil Adams, october 8 1999

funneefarmer
11-13-1999, 02:01 PM
May I make a suggestion?

Draw a line across the nail with nail polish. Then damage the nail unevenly, by cutting or whatever other method. Note the progress of the line of polish on your nail. Get back to us in a couple of weeks with the result.

Konrad
11-13-1999, 03:02 PM
Nanobyte: Do you also believe hair grows faster if you shave?

DrMatrix
11-13-1999, 08:19 PM
Sue said the faster growth is an illusion. Then nanobyte said "Observation certainly proves that what you say is untrue." Do you know what illusion means?

Thank you Sue for your answer.

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Virtually yours,

DrMatrix

NanoByte
11-13-1999, 10:32 PM
Healthy nails of people in most occupations do not "wear" down. They keep getting longer until they break or someone cuts them. If a nail is well-trimmed and a part of it breaks, and you don't cut any of the nail, both sides will grow outward, but their lengths will differ less as they do. The longer side does not "wear down". There is normally nothing around to make it wear down. There appears to be some mechanism that creates more growth on the broken side than on the unbroken side. If there is not, then some other explanation is in order, other than saying the longer portion of the nail "wears down", or the length equalization is an "illusion". Cut a nail of yours and "observe" your own "illusion".

Is DrMatrix an MD or a doctor-lover? There seems to be a bunch of the latter here. If something can be categorized within the "medical realm", we must suspend objective analysis and let MDs do their role-playing thing? Phooey!

The one from the funny farm:

Drawing a line on your nail with nail polish, of course, won't prove anything. Your nail, in adjusting the relative lengths of the two different-length portions, will certainly distort, in the adjustment process, the line that you draw.

B_Line 12:

Is your idea of reality what's written in a medical journal? Do you believe things are necessarily written in medical journals because they were consistently objectively observed. Haven't you ever noticed how many of such writings start out with claims that end up "proven" by the end of the writing, but with only nebulous associations stated in between? Most of those medical journals would take up far less shelf space if they only had cloacae in them.

Ray (If your nails wear down, quit scratching the blackboard. Role-playing is for fiction; reality requires observation of the real world, not linking to a medical journal.)

Court Jester
11-13-1999, 10:46 PM
I should probably take this to the pit, but I won't. You sir are an idiot. Nails (both finger and toe) grow from the nail bed that is under the cuticle. The amount "pushed out" is pretty much constant across the width of the nail. I have no idea what your problem with MD's is, but it does grow tiresome quickly. You asked a question, you got a logical, well thought out answer. You attacked the answer because it was from an MD. You stated that your observations were better than hers. Why? One assumes that you would only observe your own nails, while a Doc, no matter what his specialty, would see many nails.
By the way, nails do wear down, even without cutting. As you drag them across your bed spread, the table, your clothes or skin, you cause friction that erodes the nails.


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A hat with bells on is not funny, it is the jester underneath.

Kat
11-13-1999, 11:07 PM
The one from the funny farm:

Drawing a line on your nail with nail polish, of course, won't prove anything. Your nail, in adjusting the relative lengths of the two different-length portions, will certainly distort, in the adjustment process, the line that you draw.

I think that was the point.

A doctor-lover? Where? Lynch him. As for that doctor...well, Heaven forbid that just because a person spends 4 years of college and 4+ years in medical school learning about the human body and who knows how many years practicing medicine that she should believe that she could know anything at all about fingernails. She's obviously deluded. I bet she doesn't even have any fingernails of her own.

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Your Official Cat Goddess since 10/20/99.

Semper Ubi Sub Ubi

Kat
11-13-1999, 11:13 PM
As I re-read that last post, I noticed that some sarcasm seems to have crept in. I hope no one was inconvenienced, blinded or scarred for life by that little slip.

Fyodor
11-13-1999, 11:23 PM
Trivia: On the old-fashioned sea-going sailing ships a very common injury was to have all your fingernails popped off. You've probably seen in movies where the sailors all scramble up into the rigging and line up along a yardarm, standing on ropes, and start to claw up the sail canvas with their hands. If this was during a storm the wind might pop the canvas as they clawed it up and a lot of the sailors, when they descended, would have bloody hands and be missing most, if not all, their finger nails. And you thought you had a tough job.

DrMatrix
11-14-1999, 12:27 AM
In the middle of one of his rants <bNanoByte[/b] asks:Is DrMatrix an MD or a doctor-lover?I am not an MD. DrMatrix is just my UserName. If I am not mistaken our friend Sue is an MD. So I quess I am one of the doctor-lovers.
Jeez, chill out.

NanoByte
11-14-1999, 01:11 AM
Strange sort of jester:

You list yourself as "Member". Do you claim you have authority to take a thread to The Pit?

You, of course, decided I was "an idiot" by reading medical journals and linking to Web pages, right? Is that what Straight Dope means?

Nails (both finger and toe) grow from the nail bed that is under the cuticle.

Of course, I do not quarrel with that at all.

The amount "pushed out" is pretty much constant across the width of the nail.

I agree with that only where the distal edge is more or less equidistant, across its span, from the cuticle.

You asked a question, you got a logical, well thought out answer.

That's your opinion, but what is the worth of an opinion of a jester throwing out epithets? It's clear that what she said was nota "logical, well-thought-out" answer. She claimed the unbroken part of a partially broken-off nail "wears off" so sufficiently as to make it "illusive" that the two sides of the nail conform fairly closely, before the long side grows too long, but at such time as the broken side reaches essentially the desired length. That explanation is clearly just cranked out to fill the gap, so to speak, since, if nails simply "wore" off at such rate, people would not always be cutting them.

You attacked the answer because it was from an MD.

I attacked the answer because it made no sense, clearly did not result from even from ordinary observation, and was obviously a stereotypical MD response simply parroting a thesis resultant from the basic rote-learned medical memorization of the fact that the nail grows only from its root end; and that, if it be observed that the two sides grow other than in equal amounts, it is just an "illusion". Yes, everyone other than MDs, and those who shrink from contesting their half-baked answers, run around seeing illusions all the time.

You stated that your observations were better than hers. Why?

I stated that her answer made no sense, because observation of my nails and of others practices of having to cut off nails at a frequent rate, if they don't want them too long, constitutes clear evidence that the amount that normal nails "wear off" is insignificant. I certainly don't deny that they lose a timy, insignificant amount of their length from wear. I also, however, note what it takes to file down a nail -- vastly more abrasian with very rough material, than the nail ever meets otherwise. It would seem to me that a site labeled The Straight Dope would support posting that was not just "professional" hiccups without real-world content. The Web elsewhere is a madhouse of MDs and others jabbering various degrees of "health-care" factoids.

One assumes that you would only observe your own nails, while a Doc, no matter what his specialty, would see many nails.

Do you really believe MDs "see" more nails than you do? I don't know how much, or in what area(s), this MD specializes; but, from her answer, I would have to assume that she spends little time actually observing how nails grow. You'd probably be better informed talking to a mani/pedicurist on this subject (which is not really medical), than to an MD not specialized in nail care (and I don't know of any that specialize beyond dermatology in general).

As you drag them across your bed spread, the table, your clothes or skin, you cause friction that erodes the nails.

And you don't believe it matters whether this happens at the rate of 3 molecules per day or 0.050" per day? Clearly, you do not care about the importance of the rate at which something happens, so long as you can say it happens.

A hat with bells on is not funny, it is the jester underneath.

Yes, I'd say the jester underneath, in this case, comes out quite "funny". Maybe he has bats where he should have bells.

Kat:

quoting me:
"Drawing a line on your nail with nail polish, of course, won't prove anything. Your nail, in adjusting the relative lengths of the two different-length portions, will certainly distort, in the adjustment process, the line that you draw."

I think that was the point.

So, how would you describe the difference in the shape/position of such a line, under the two outcomes that are in conflict in this thread?

As for that doctor...well, Heaven
forbid that just because a person spends 4 years of college and 4+ years in medical school learning about the human body and who knows how many years practicing medicine that she should believe that she could know anything at all about fingernails.

You express here exactly the sort of disgusting outlook that provides this society with such in- or negatively effective physicians. And this subject isn't really a medical one. No MD can become any measure of hero in understanding how finger- or toenails grow/adjust. But, more generally, you throw out the absurdity here that MDs are always spouting -- that they should get paid according to how many years it took them to get through school -- schooling that mostly consists of simple, rote memory, rather than taxing reasoning ability. I've observed those people around Stanford and all the games they play. Role-playing and memorizing is not learning how the body actually works while either whole or damaged.

I noticed that some sarcasm seems to have crept in. I hope no one was inconvenienced, blinded or scarred for life
by that little slip.

You figure a little sarcasm will "scar somebody for life"? Maybe you ought to figure out what years in school learning to role-play, when collectively pursued by a whole exclusively society-entrenched profession, can do to people.

Al Zheimers:

An interesting note about the sailors' fingernails, but I hope it wasn't intended to impact the issues in this thread. (Not many of us scramble up the rigging these days. . .but if we did, and we lost a fingernail or two, we'd probably sue the ship owners out of existence. ;) )

Ray (Hit the nail on the head; don't just wear it down.)

TheNerd
11-14-1999, 01:35 AM
Ray, in the experiment proposed by funneefarmer, the line would remain more or less in it's original form (though pushed out a little from the cuticle) if you are wrong. If you are right, then the portion of the line nearest the damaged part of the nail should deform outward faster than the rest of the line, leaving a pronounced bell-curve sort of shape.

AuMatar
11-14-1999, 01:53 AM
I may be able to bring in a little experimental data here. When I was a young kid (7? 8? around there), something happened that caused me to have a thumb sucking problem while I slept. Anyway, by the time I went to the doctor, the nail was erroded allmost all the way to the cuticle, but it was eroded in a curve, something to do with the angle I stuck it in my mouth at. So I had ample time to observe the nail grow back, as it took at least a month to do. It grew at a fairly constant rate, the part that was more worn down did NOT grow faster to meet the other end.

Also, for a logical argument, assume Nano is right. The nail grows by being pushed out, not by adding to the front. So all one side growing faster would do is cause that side to push out more, making your entire nail curve off. Also, in response to one of his other posts, the destruction of a nail is far more than a few molecules per day. It is actually shaved off at a good clip. The only thing is that it grows fastert than it is shaved, so it doesn't appear that way.

dasmoocher
11-14-1999, 02:10 AM
I'm starting to wonder if the sun really rises… Just how would a nail know to grow faster on one side if the distal edge on that side was shorter than the other edge? Must be some undiscovered property of keratin. Those bullshit medical journals have obviously neglected this important phenomena; there's nothing worth reading in them anyway.

funneefarmer
11-14-1999, 05:25 AM
Well I'm glad someone thought a real life experiment would be a good way to find out the straight dope. It's a shame that the original poster doesn't feel the same way.

Nickrz
11-14-1999, 05:53 AM
I nominate this thread for The Straight Dope "Please Set Claw Depth" award.

Let's try to be civil to one another.

(I'll perform Ray's experiment, but you'll have to wait awhile for the results. I have snail nails).

11-14-1999, 11:35 AM
In the more light, less heat category of posts...

1. Nails are acellular, non-living material. They are mainly made of the protein keratin, which is laid down by the nail matrix, which is under, and slightly closer to the wrist from, the cuticle.

2. The rate of growth of finger nails varies tremendously from person to person, and even from finger to finger (thumbs are the fastest), but does NOT vary from side to side to side of a given nail.

3. Cites for this are difficult to come by, since this falls in between what is available in the on-line Comptom's & what is published in medical journals. Here is a decent basic info site: http://nh.ultranet.com/~mhabif/html/anatomy.html

4. Nails grow at a pretty steady rate, gradually slowing down as we get older. Even though healthy nails constantly grow, they lengthen at a slower rate, because the tips of them are being worn down at a rate slower then the rate of growth.

Rate of growth = a mm/month
Rate of wear = b mm/month
a > b
Rate of lengthening = a-b mm/month

Note: b varies with nail thickness/hardness, nail length, and the harshness of hand activities.

5. Think of a nail file or emory board, Ray. It is pretty easy to shorten nails by a measureable amount in a few minutes with one of these. Albeit more slowly, the same thing happens when our fingertips run across any rough surface.

6. When part of a nail is lost, the part that remains at normal length projects further from the nail bed than the damaged section, thus it is more exposed to normal wear, while the damaged portion of the nail is protected.

Rate of lengthening for damaged nail = a (since it is protected from wear)
Rate of lengthening for undamaged nail = a-b

Since a > a-b, the damaged nail appears to be catching up to the undamaged section.

Rate of growth for the entire nail = a.

7. You certainly can try the fingernail polish experiment if you choose. Or you can accept what quite a few people have told you. I can tell you that fingernails sometimes get horizontal ridges, or white bands, indicating keratin that came out differently during a period of illness, nutritional lack, or trauma to the nail matrix. I have looked at a lot of fingernails, Ray. These lines have always remained perfectly straight, with no distortion whatsoever, in every case.

btw, "take it to the pit" means that the discussants start a new thread in the Pit to continue their rants, rather than clutter other forums with closed-minded, prejudiced diatribe.


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Sue from El Paso

Experience is what you get when you didn't get what you wanted.

Kat
11-14-1999, 01:37 PM
You express here exactly the sort of disgusting outlook that provides this society with such in- or negatively effective physicians.

No, I take exception to your constant haranguing of physicians and your implications that they know nothing about the human body. Jesus, we learned how fingernails grow in my freshman biology class, so forgive me if I believe that physicians, who take much more biology than I, and probably you, ever did, might conceiveably know more about it (biology and the way the human body, including fingernails, works) than I do.

But, more generally, you throw out the absurdity here that MDs are always spouting -- that they should get paid according to how many years it took them to get through school -- schooling that mostly consists of simple, rote memory, rather than taxing reasoning ability.

1) Please quote where I said one word about money or pay.
2) If you think all that doctors do in college and medical school is memorization...I'm not going to finish that sentence, because it's get nasty.

You figure a little sarcasm will "scar somebody for life"? Maybe you ought to figure out what years in school learning to role-play, when collectively pursued by a whole exclusively society-entrenched profession, can do to people.

Umm...that was more sarcasm.

JimOfAllTrades
11-14-1999, 04:41 PM
Observational data which may be germain:

My work switches me from the office to the work site on a regular basis. I'll be in the office for anywhere from a week to several weeks, then spend a day or two at a scalehouse, or working in an industrial process control setting, or pulling wire & cable through some wall or crawl space.

I keep my nails fairly short out of habit (hey, I'm a guy), but when I move from the office (where they are relatively protected from major damage) to the work site, I'm pretty much guaranteed to break one or two if they extend at all past my finger tip. So I'm frequently in the situation of having a nail that's been broken off, sometimes very unevenly.

My nails, at least, do not seem to grow at an uneven rate from side to side. I have to trim the undamaged side several times, often over over a couple of weeks, before ever having to trim the damaged side.

The assorted lines on my nails caused by smacking them various tools always seem to stay at the same relative angle, again sometimes for weeks, while the damage grows out.

So for me, anyway, the situation is exactly as described by MajorMD and the others who disagree with the OP.

Ugly

Drain Bead
11-14-1999, 08:14 PM
[hijack]

Sue,

I must have smashed the crap out of one of my fingers without knowing it, or slept on it wrong, or something. I woke up once in the middle of the night with the tip of my middle finger on my left hand about twice the size of the other fingertip. I took some Aleve, soaked it in peroxide, and forgot about it.

Two weeks later, I notice a yellow spot growing out on one side of that fingernail. It got bigger and bigger, and after it grew out for a while, started cracking. I now have a large hole in the base of my nail, and there's no sign of new nail growing up to replace it.

What the hell have I done to my finger?

[hijack]

Lord Jim
11-14-1999, 08:44 PM
I have a real life experience to add to this thread, though it doesn't seem to be what is driving it. I can't even make enough sense of all the bickering to know which side of the arguement this may fall.
I have two fingers with flaws in the nail for a long time (long time). The nail on my right thumb is split back beyond the cuticle, the two parts grow completely independent of each other. The right side is about 1/8 inch wide and it seems to grow slightly faster than the main portion of the nail. As, when the nail needs cutting, the smaller portion is slightly longer than the nail right next to it that is part of the main nail.
Now to the second finger of my right hand. (ok, I'm left handed, my right hand is the sacrificial lamb). It has a damaged portion just on the right side of the center about 1/16 inch wide. The two portions of the nail are not separated but the damaged area is very thin. If the nail grows out even slightly it will split into the thin part and has to be cut back way too far to get beyond the split. Both sides seem to grow at the same rate.
Now, my deductions. In the case of the thumb, the 2 portions are growing independently but at close to the same rate, although not exactly. In the case of the middle finger, the entire nails grows at a certain rate and if a damaged area can't supply the needed material then it is just thinner and weaker.
Now, exactly whose side this ends up supporting, I don't have a clue, but I would like one answer and that is, how anyone can take something like the way a finger nail grows to the level of attacking another personally or should that be another thread entirely.

11-14-1999, 09:34 PM
Libby asks:

Sue,

I must have smashed the crap out of one of my fingers without knowing it, or slept on it wrong, or something. I woke up once in the middle of the night with the tip of my middle finger on my left hand about twice the size of the other fingertip. I took some Aleve, soaked it in peroxide, and forgot about it.

Two weeks later, I notice a yellow spot growing out on one side of that fingernail. It got bigger and bigger, and after it grew out for a while, started cracking. I now have a large hole in the base of my nail, and there's no sign of new nail growing up to replace it.

What the hell have I done to my finger?


Uh... If you could have "smashed the crap out of...one of (your) fingers" without remembering it, I'm left to wonder what or who else was smashed. ;)

Seriously, this is not something I can diagnose over the 'net; 2 likely causes are infections or foreign body under the cuticle.

If I'm hearing you right & the "hole" is growing into a linear gap, do go see a doc - one who can/will do scrapings & look at them under a microscope, or who will send to someone who will. If you can self-refer to a dermatologist, do that.

Good luck!




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Sue from El Paso

Experience is what you get when you didn't get what you wanted.

moriah
11-14-1999, 10:07 PM
While Nanobyte often participates in a jocular, informative manner in most subjects, he has been known to go on knee-jerk anti-MD rants as a matter of principle. It's obvious that, to him, the medical community is a big sham. So, take his critiques of medical knowledge in that light and ignore him.

Peace.

11-14-1999, 10:16 PM
::Note to self - Never hold a nail if Jim is hammering::

Jim, I'm sorry you had to read through the nastiness. Looks like you're a fairly new poster. I don't know how long you've been lurking, but when you see that much venom with no obvious source, there's a history somewhere. Sometimes it's on-line, where bad feelings have been caused by other posts in other threads; sometimes it's just the emotional baggage we all carry. Nanobyte has posted on several threads his feelings towards docs; I don't know the history behind that, but I'm sure there is one. Other readers, apparently, are tired of having to pick their way through the minefield.

Your finger agrees with everything I said. The fact that your thumb nail segments have different growth rates allows me to elaborate on my basic answer (which assumed that the nail was intact). Nails that have completely or partially lost contact with the nail bed underneath them do grow faster. I suspect that the small part of your nail is less strongly attached to the nail bed.

By the way, if this piece causes problems, it can be removed & if the nail bed is destryedm that small section will not grow back - same treatment as for ingrown hangnails.


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Sue from El Paso

Experience is what you get when you didn't get what you wanted.

11-14-1999, 10:25 PM
destryedm = destroyed of course.

#$^&(* keyboard.

11-14-1999, 10:28 PM
Ingrown nails, not hangnails. Sheesh!

Lord Jim
11-15-1999, 09:07 PM
Sue, thanks for the info. Been reading the message boards for a little while, straightdope for a long time. I don't normally post though. (lurkng is such a harsh term).
::Never hold a nail if Jim is hammering::
Good idea, that's exactly how it happened. But it's been that way for 30 years(did I say that?), so it isn't a big deal. The middle finger flaw is much more bothersome and it came from and infection.

Lord Jim
11-15-1999, 09:36 PM
Oh, and Sue, also you are probably right about not being in less strongly (I like that phrase, kinda like more weakly, only different) attached to the nail bed. As the small portion of the nail grows out, it seems to get more loosely, or is it less tightly, attached to the nail bed to the point that it seems it could pull completely loose if it isn't trimmed back.

11-16-1999, 12:11 AM
TheNerd:

I agree. I assume the amount of distortion of the line would be greater for a more distal line.

AuMatar:

Also, for a logical argument, assume Nano is right. The nail grows by being pushed out, not by adding to the front. So all one side growing faster would do is cause that side to push out more, making your entire nail curve off

Up until the last word of this, 'off', it describes what I've observed and stated in my OP; i.e., the damaged side grows a little faster and tends to catch up with the undamaged side, making the two sides more even, and usually nearly even, before the undamaged side needs to be trimmed. If your word 'off' means (with 'nail curve' = 'distal edge of nail') the distal edge of the nail is more extended on the damaged side, what you say seems to present a case where the damaged side would actually overtake the undamaged side. I certainly didn't claim that would happen.

,. . .the destruction of a nail is far more than a few molecules per day. It is actually shaved off at a good clip. The only thing is that it grows fastert than it is shaved, so it doesn't appear that way.

I have, of course, not counted molecules (probably these are long chains that get broken from abrasion anyhow, so I wouldn't want to use that sort of measure), what I was trying to say was that the rate of abrasion is negligible wrt rate of growth of either portion of the nail.

647:

I'm starting to wonder if the sun really rises…

Hey, we're talking here about a damaged part of a nail catching up with the nail's other part. . .not Flatlanders catching up with modern astronomy. ;)

Just how would a nail know to grow faster on one side if the distal edge on that side was shorter than the other edge? Must be some undiscovered property of keratin.

I didn't say I knew, right? I just observed what happens and then asked this 'how' question in general, however[/b] whatever materials might get into the act. The Web page Sue linked to here suggests, though, how this might occur. See my discussion in this post directed to Sue, below.

,. . .I'm glad someone thought a real life experiment would be a good way to find out the straight dope. It's a shame that the original poster doesn't feel the same way.

Where did I say I didn't feel it wouldn't? My OP question, of course, as a result of [i]my observations, went on from the position of acceptance of the catch-up phenomenon to ask what the mechanism for it might be. From you others' standpoint of not accepting this premise of mine, of course, the mere existence or nonexistence of the phenomenon needs to be established, and of course, the best Straight Dope way is a real-life experiment that first off demonstrates that the phenomenon either exists or not.

Nickrz:

Let's try to be civil to one another.

I just don't think this place should turn into a doctors' or lawyers' public-counseling session. I think MDs and JDs/LLDs should be required to play here by the same commonsense and scientific rules that others are susceptible to on objective, real-world questions here in this MB.

I have snail nails.

Well, we don't have forever. I think a webcam focused on someone with fast-growing finger- or toenails should be set up at this site. You should get the SD staff to do this. Rotsaruck. You don't think they'd think it was as important as the duck-echo experiment? (And you know it wouldn't make the WSJ, like the HUD fiasco.) A sped-up time-lapse video clip of a semi-damaged nail would be good, only if there were some way to establish it's authenticity. Maybe the webcam thing could be used for increased SD publicity, ya think? Not enough sex? Nobody but foot fetishists would be attracted?

Sue:

The rate of growth of finger nails. . .does NOT vary from side to side to side of a given nail.

Well, yes, that has been your claim and that of some others here. I do not disagree with that, of course, in the case of a normal, undamaged, undiseased and not-irregularly-broken-at-its-distal-end nail with normal supporting and productive tissues. I doubt that you are claiming no sidewise growth variation in the case of nails with their productive tissues damaged or diseased. I'm not sure what you would say about nails with healthy, fully functioning productive tissues but which have "disease" in them per se. Would you recognize that a fungus chomping on the keratin only could vary the net rate of extension of the nail's distal edge, from side to side, in the same manner the significant differential abrasian you claim, in the case of a partially broken nail-end, would do?But I understand that our contest to be probably only over the such sidewise net-extension/growth variation in the case where nothing is nonuniform from side to side, except the amount of breakage at the distal end of the nail. Furthermore, I am claiming the existence of this growth variation, whether or not the breakage extends back to a part of the nail that is not bonded to the bed.

Cites for this are difficult to come by. . .

Truth is difficult to come by.

Rate of growth = a mm/month
Rate of wear = b mm/month
a > b
Rate of lengthening = a-b mm/month

Yes, of course, but I say b << a, i.e., negligible within, say, a normal office worker's lifestyle while not engaging in any obviously nail-eroding activities. I am impressed that, as an MD (a generally math-hating profession), you at least go so far as to outline a physiological issue in algebra. However, if the relative magnitudes of the parameters so designated are not established for the given problem space, you cannot claim anything more useful than what one finds in the many books of nebulous would-be theoreticians who go so far as to form sentences in math notation, while contributing nothing to make one believe they are presenting anything more than they would've, had they phased the same thing in a verbal language.

Think of a nail file or emory board, Ray.

Well, I have actually gone further and used one on my nails, and I'm impressed at how much more shearing action is involved with such a tool -- where it is a normal, full-sized, quality one or the other -- than is involved in any other material contact that goes on with my fingernail tips. You know, I never did get into the habit of getting a rise out of my teachers and classmates by scraping my fingernails on chalkboards (in the good old days). I also note how totally ineffective, in the filing of my nails, are miniature key-ring-clipper nail files. A nail of mine could outgrow what I could file with one of them, no sweat.

Rate of lengthening for damaged nail = a (since it is protected from wear)
Rate of lengthening for undamaged nail = a-b

Since a > a-b, the damaged nail appears to be catching up to the undamaged section.

Rate of growth for the entire nail = a.

Since b << a, and here, even more << than above (here, a difference in wearing), definitely no significant catch

11-16-1999, 12:11 AM

11-16-1999, 12:11 AM

PUNdit
11-16-1999, 12:43 AM
Just a note to say that Majormd (Sue) is away at a medical conference and will not see this post until Thursday at the earliest. I don't know if she will choose to reply, but I didn't want the intervening silence to be taken in the wrong way.

And Ray, you make some claims about MD's and their education. While these may not be directed at Sue directl, I think that you should know a couple of things about Sue that she would never tell you herself. She has a BS in Microbiology (Phi Beta Kappa) and an MS in Biochemistry. She received these degrees in 9 semesters. She then worked in a hospital lab for four years before attending Medical School. She was in the top 10% of her graduating class, and an Alpha Omega Alpha (med school equivalent of Phi Beta Kappa) graduate. Oh yeah, I forgot to mention, she was required to take Calculus 1 for her degree program, she took and made A's in Calculus 2 and 3 because she enjoys math.

PUN
(Proud husband of Sue in El Paso)

NanoByte
11-16-1999, 01:12 AM
Uh-oh, now that you spilled the beans. . . ;) Well, yeah, she's obviously more than a cut above the rest intellectually, and I guess in some other ways. My main concern here is really how the others act, once an MD or attorney comments on something here. Categorically, those in both fields are extremely underwhelming and overbearing.

Ray

ChuckSki
11-16-1999, 07:40 AM
Maybe I can shed some empirical light on this.........

I have a (nasty) habit of cutting my cuticles back with an exacto knife (please, no lectures while I'm humbling myself to this cause). I sometimes get a bit beyond just cutting the cutlicle, to the point where I'll actually 'score' the nail with a perfect outline of the cuticle.

In an embarassing exhibition of my roofing ability three week ago, I damaged a nail I had scored as above. I fortunately still have the reflexes of a (big) cat, and was able to get away with striking only the very tip of my left index finger nail, cracking off a jagged piece on the thumb side for about 1/3 of the nail width, to a depth of about 1/3 of the way to the cuticle (from where it attached under the tip of the nail.

As I sit here now, the scored line is about 3/4 of the way up the nail, and appears as it was when originally scored. The damaged area has just been trimmed away to 'even' today.

My observation is that MY nail grew at a common rate across the nail. I'm not sure how a nail could grow at different rates. I thought the nail itself was , basically, 'dead'. How would one part grow past the other? Well, in my experience with this one nail, it grew the same across the damaged and undamaged part.

Chuck L.

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"The intellectuals' chief cause of anguish are one another's works."
Jacques Barzun
Cheers! CAL

moriah
11-17-1999, 01:46 AM
Moriah, the wind person, I see, is still blowin' it out.

At least I'm not long winded.

Peace,

moriah (also not mariah)

NanoByte
11-18-1999, 12:50 AM
You know, when I put either 'moriah' or 'mariah' into AltaVista search engine, I get an awful lot of associations of both of them with the wind. How do you get the real Wind to stand up and blow the other one out?

Ray

Crittermaker
11-20-1999, 05:10 AM
Apologies in advance to anyone who's reading this while eating. A couple of months ago, my left thumbnail was ripped out in a bizarre puppetry accident. The normally hidden bottom part of the nail was pushed through the skin that covered it, resulting in the loss of the nail, a large gash at the base, a hydrant's worth of blood and lots of ugly damage to the skin under the nail. It was reconstructed and after a while, I began to realize that what I thought was thickened skin over the area was actually the nail reforming (as of tonight, it's obviously a complete nail again). The odd thing is, the part of the nail to the right of where the gash had been is growing a lot slower than the part on the left (there's almost a quarter-inch of difference). I hope this helps to illuminate something about the topic, because if not, all I've succeeded in doing is making everyone ill.

DrMatrix
11-20-1999, 04:56 PM
NanoByte suggests:I think a webcam focused on someone with fast-growing finger- or toenails should be set up at this site.
I LOVE this idea. Not only would this resolve this question which has plagued mankind (with the exception of the medical community) for so long, but it would be entertainment for those people who find watching paint dry way too exciting.
ROTFLMAO
I love you guys.

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Virtually yours,

DrMatrix