Kuro5hin.org: technology and culture, from the trenches
create account | help/FAQ | contact | links | search | IRC | site news
[ Everything | Diaries | Technology | Science | Culture | Politics | Media | News | Internet | Op-Ed | Fiction | Meta | MLP ]
We need your support: buy an ad | premium membership

[P]
The Cause of RSI

By Alan Crowe in Science
Sun Dec 01, 2002 at 08:14:32 AM EST
Tags: Science (all tags)
Science

An intriguing, but unresearched, speculation as to the cause of Repetitive Strain Injury.

Could it be the light action and short travel of modern keyboards and mice that cause the trouble? Dysponetic activity (inappropriate and misdirected as well as unconscious muscle bracing) is implicated in the aetiology of RSI. How much of this is due to the need to support the weight and muscle tone of one's fingers to avoid inadvertent key presses?


Keyboard action and muscle antagonism

Muscles are single acting; they can pull but they cannot push. Joints are double acting; they are powered both ways. The secret is that muscles come in antagonistic pairs, one to flex the joint, and on the other side, one to extend it. See also here and here

This is like the p-type and n-type transistors in CMOS. Turn on the n-type transistor to pull the output low. Turn on the p-type transistor to pull the output high. Both off at the same time for tri-state. Both on at the same time to short out the power supply and blow up the chip. In the human body, both muscles are off in the relaxed state. If both muscles are slightly on, this pre-stresses the tendons, taking up any slack, and effectively stiffening the joint. This is what you do for exacting fine work, e.g. embroidery or surgery. This is why such work is tiring, even when the external forces you exert are small. For ordinary work, you must coordinate your muscles so that they are non-overlapping.

When you type on a mechanical typewriter, you push hard. I've just been measuring my old Olivetti Lettera 22. The keyboard is open underneath so it is a simple matter to dangle an icecream tub underneath and fill it with water until the rachet clicks to advance the carriage. 1.12 kg. 17mm of key travel. Using g=9.81 ms-2 we can work out the energy to type a character as force times distance: 9.81 * 1.12 * 0.017 = 186mJ. If you are typing 30 four letter words a minute that is (30/60.0) * (4 + 1) * 0.186 = 0.464 W. It is not hard physical work.

The test mass of 1.12 kg weighs about 10 Newtons, which feels like a lot if you are not used to it, but the significance lies elsewhere. It is way more than the force exerted by the relaxed tone in the muscles that control your finger. So to type a character you turn a flexor full on, and turn it back off again. The typewriter is geared at about 6 to 1, much like a piano, so the hammer is flying pretty fast. Its momentum slams it into the paper, making the impression and the rebound and the little coil spring in the typewriter bring your finger and the key back up. You literally never lift a finger. The springs in the machine lift your fingers for you. You can type with the extensor muscles relaxed all the time. Touch typing on a manual typewriter requires alot of coordination, but it does not require every kind of co-ordination. In particular you do not have to co-ordinate your flexors and extensors to avoid having them both on at the same time, because you never turn on your extensors at all.

The modern mouse

A modern mouse is very different. If you just plonk your hand down on top of it you click all three buttons. You have to use your extensors to not click. When I restarted using a computer after a lengthy illness, I rapidly got pains in my arms, from holding my fingers off the mouse buttons all the time. I had to learn to be just tense enough to stop the natural curl of my fingers from clicking the buttons. What happens when I click a mouse button? What is supposed to happen is that the extensor is turned off then the flexor is turned on, then the flexor is turned off, then the extensor is turned back on, so that they don't overlap. I've not done any electromyography, but I don't believe it is happening like that. Briefly relaxing a muscle that is kept tense most of the time is difficult and time consumming. I bet that the flexor is turned on hard to over come the extensor. How much damage does that do? It probably depends alot on the office environment. If you are generally relaxed and have only just enough tension in your extensors to avoid accidental mouse clicks, I cannot see it doing much harm. If work is fraught, and you tense up to avoid mistakes, beware. The forces exerted when your flexors and extensors are on at the same time add up internally, but cancel externally. You might think that you cannot be stressing your tendons because the switches have a light action and you are not exerting much force, but if that force is the difference between the force exerted by the flexor and the extensor, your tissues might be under a great deal of internal mechanical stress.

I suspect that much the same goes for a modern keyboard. You have to actively lift your fingers off the keys after the stroke. You don't have the option of flexor-only typing. So when work gets hectic and pressured, and your coordination is not 100%, you get flexors working harder to overcome extensors that are not being fully turned off, and lots of internal mechanical stress.

Internal Stress

My theory is that these internal stresses are larger than with a clunky old mechanical typewriter, and are the cause of RSI.

How can one find out if this theory is true? One way is to get a researcher interested enough in this theory to use electromyography to investigate the patterns of muscle use. The point about both muscles being turned on at the same time appears to be well proven in the work of Peper et al. , with pictures here They use surface electromyography (SEMG) as part of rehabilitation training, and their goals include

Inhibit finger/wrist flexor/extensor SEMG activity when fingers are resting on keyboard.
Potvin is following the same line of inquiry. Both groups of researcher appear to assume that modern electronic keyboards with a light action and a short travel are a given. My question is, what happens when you use a heavy, long travel keyboard, such that you can plonk your fingers down on the keys without fear of accidently pressing them? Does this avoid the development of flexor/extensor SEMG activity when at rest?

Another research strategy is simply to get keyboards and mice with heavy, long travel keys. This would make sense in a prospective study, in which you equip half a cohort of new users with the clunky mouse and key board, and follow up after five years to see who has RSI and who hasn't.

Merely using a heavy, long travel keyboard is implausible as a treatment. If you have learned to type on a light keyboard with your extensors turned on, the extra force needed to operate a heavier keyboard might be translated by habit into more activation of the extensors as well as more activation of the flexors. I cannot see a heavier keyboard in itself working as therapy, unless the sufferer can learn the flexor only typing technique it permits, and avoid falling back into flexor/extensor overlap habits when work gets hectic.

Sponsors

Voxel dot net
o Managed Hosting
o VoxCAST Content Delivery
o Raw Infrastructure

Login

Related Links
o single acting
o antagonist ic pairs
o here
o here [2]
o electromyo graphy
o Peper et al.
o here [3]
o Potvin
o Also by Alan Crowe


Display: Sort:
The Cause of RSI | 76 comments (64 topical, 12 editorial, 1 hidden)
Qwerty caused my RSI (3.66 / 3) (#2)
by tacomacide on Sat Nov 30, 2002 at 06:02:16 PM EST

Dvorak is much nicer.

*** ANONYMIZED ***

Ditto (4.75 / 4) (#11)
by evilpenguin on Sat Nov 30, 2002 at 08:38:21 PM EST

I switched to Dvorak after I got to the point one night last summer (after about 36 hours of coding) where I couldn't type anymore -- the pain became more unbearable with each keystroke.  After that night, I couldn't type for about a week (somehow, though, I could still play the guitar and double bass with little pain).  When I finally got better, I popped the keys off my Model-M and arranged them in the Dvorak layout.  A quick "xmodmap" later, and I'm good to go.

I made the switch last July, and it was certainly... an experience.  It's like I was three all over again and had to "hunt-and-peck".  And as an added bonus, all my computers at work were still QWERTY (I couldn't switch them; there was multiple users), so learning the new keymap almost halted my old ability too!  It's so frustrating not being able to type (especially as a *nix user, because I do everything at the shell), to the point where you want to just give up.  It's almost as drastic as forgetting how to write or speak.

It took me about a month to get back to my average QWERTY speed (~70 WPM), and about three months to be able to reach my QWERTY max (90 WPM).  But now I've beaten my old QWERTY record (I reached 121 WPM in a gtypist sentence exercise), and I'm able to do so without my hands aching.  I can't understate the value of Dvorak -- sometimes I feel like I'm just typing on air, or fretting notes on a guitar -- the emphasis on the home row really makes that much difference.

I still used QWERTY at work throughout this whole process, so I am still able to mentally switch between the two, but my QWERTY speed has degraded somewhat from lack of use (70 WPM max).  Most likely, you'll still have to be able to use QWERTY, so maintaining a reasonable speed with the latter is worthwhile.

The only pitfall is vi.  I use elvis (and love it), but the vi control keys were _made_ for QWERTY -- "hjkl" is the most annoying switch (a close second is 'd', which is where 'h' used to be, so you may hit that accidentally a few times).  I've gotten used to it, but the QWERTY layout still feels more natural, so I'll probably end up re-mapping the keys in vi to be QWERTY in command and ex mode, while still Dvorak in input mode.

I wholeheartedly reccomend Dvorak to anyone -- RSI or not.  You'll type faster with greater accuracy and less pain.
--
# nohup cat /dev/dsp > /dev/hda & killall -9 getty
[ Parent ]

VI (5.00 / 1) (#49)
by iso on Mon Dec 02, 2002 at 12:07:28 AM EST

Vi was my primary concern when I was considering switching to Dvorak (I never did end up doing it). There are Dvorak layouts for vi for just this purpose.

Check out: http://chronos.cs.msu.su/vim/howto/dvorak.html.

I haven't tried it personally, but I'd be curious to see how it works for you.

- j



[ Parent ]
similar concerns (none / 0) (#58)
by The Shrubber on Mon Dec 02, 2002 at 11:30:21 AM EST

I'm perfectly happy using vi(m) with dvorak, the exception being that the ":" is located where the qwerty "Z" is... which means that i essentially replaced emacs-pinky with vim-dvorak-pinky from stretching that finger and hitting the colon all the time.

Does anyone have any hints?  Any minor changes to my vimming habits?

Maybe i should re-emigrate to something like Nedit, but vim just seems to fit my personality so well.

[ Parent ]

foot paddles (none / 0) (#59)
by The Shrubber on Mon Dec 02, 2002 at 11:33:23 AM EST

if anyone wants to make me a couple of mappable usb foot-paddles, i'd be in the market... that's my fantasy, one foot paddle for "," (my scripts) and another for ":"

[ Parent ]
ah. (none / 0) (#74)
by juju2112 on Thu Dec 12, 2002 at 01:18:13 AM EST

You mean something like this?

[ Parent ]
yes, thanks! (none / 0) (#75)
by The Shrubber on Mon Dec 30, 2002 at 02:58:41 AM EST

i am gleefully imagining mapping centre-switch to ":", left-switch to "," (for my custom macros), and right-switch to "Ctrl-K" (for those crazy digraphs)


[ Parent ]
Vim + remapping (none / 0) (#63)
by lb008d on Mon Dec 02, 2002 at 03:01:40 PM EST

I would consider myself an expert Vim user. I use Dvorak and only had to switch the motion keys:

map l s
map s l
map n k
map k n
map t j
map j t
set noremap
map Q gqap

The only thing you have to remember is that "k" is for the next regex match, and to use "j" instead of "t" as the "next character" motion command. I haven't bothered remapping "gj", "gk" etc since I never use them.

"Kuro5hin: politics and pretension, from the $3,000 leather recliners on the hill overlooking the trenches."DarkZero
[ Parent ]

My solution (none / 0) (#18)
by sholden on Sat Nov 30, 2002 at 10:04:00 PM EST

I type really slow with my own hunt and peck method.  I do use all my fingers and thumbs so I'm not as slow as authentic two finger hunt and peck.

It works OK for me, since my brain is slower than my fingers anyway...

I also hit the keys really hard. And love old 'clicky' keyboards, which if the article's author's theory is right is a good thing I guess...

--
The world's dullest web page


[ Parent ]
Me too. (none / 0) (#25)
by rusty on Sun Dec 01, 2002 at 03:14:30 AM EST

Though I mainly use my two middle fingers, with only the occasional middle-first combo, generally for capitals. The most mobile parts of my body while typing are my elbows. Combine this with a gummy keyboard conditioned by years of spilled coffee, which requires whaling on the keys to do anything (my wife, who touch-types is totally unable to use it) and you've got an RSI-free life so far.

____
Not the real rusty
[ Parent ]
Interesting theory (5.00 / 2) (#8)
by janra on Sat Nov 30, 2002 at 06:55:42 PM EST

And one I'd like to see researched, too.

Not that I have RSI, but I did notice that typing on "light" keyboards, such as the soft-touch silent keyboards or any laptop keyboards, is a lot less comfortable and more tiring than typing on my own keyboard, which is an old-style buckling spring keyboard, with (relatively) long key travel distances and a spring to bounce my fingers back up after pressing the key down. And a nice positive *click* to tell me that the keypress has been registered. I make a lot more typos on "light" keyboards because I simply don't know when the keyboard actually registers a letter as pressed.

I paid some attention just now to how I hold my fingers when typing and when using the mouse, and tried consciously relaxing my fingers. The mouse (Logitech 4-button funky-shaped MouseMan) didn't quite click but definitely made me think it was going to; the keyboard (Unicomp's edition of the old IBM buckling-spring "I could kill you with this" keyboard with the steel backplate) didn't at all.

I also realized while typing this that I unconsciously drum my fingers on the home row when I'm thinking, because I know the keys aren't going to register for a light tap, it takes an actual press - and that when I'm using somebody else's keyboard, that habit gets me in trouble because it presses random keys on the home row.


--
Discuss the art and craft of writing
That's the problem with world domination... Nobody is willing to wait for it anymore, work slowly towards it, drink more and enjoy the ride more.
spring keyboards... (none / 0) (#36)
by Chakotay on Sun Dec 01, 2002 at 11:57:30 AM EST

I love those too... I used to have a Mitac "killer keyboard", but changed to a Trust ergo keyboard later. My parents now have the Mitac and they love it because it clicks to confirm that you've actually pressed the key.

When I went out looking for an ergonomic keyboard, basically there were two choices open to me: Microsoft and Trust.

Disadvantage of the Trust: The 6 is on the right side, while I was used to typing it with my left index finger.

Disadvantages of the Microsoft: the area in the middle is unused (the Trust has a very useful backspace button inbetween the two halves), and the keypress is absolutely HORRIBLE. It's like the keys have pneumatic stabilisers under them, or a big wad of cotton.

So I went for the Trust, and was never deceived. An excellent and very sturdy keyboard. I can, as you also do, drum my fingers on the home row while thinking without fearing an accidental keypress. It doesn't click, but it does have a progressive force: when you press, you kind of fall through the pressure point and the press is registered. And when you relax your finger, it is pushed back up by the key.

When I type on laptop keyboards, I generally hover my fingers above the keys, which I think is a pretty bad habit, but then again, I don't work on laptops very often.

And switching to Dvorak? I'll have to think about it. I already have to juggle two keyboard layouts: QWERTY at home, AZERTY at work. I type both of them fluently now, but sometimes I do still make errors. Basically: AZERTY SUCKS!!! It's good for typing French texts, but never EVER try coding with it. Numbers require shift, slash and dot require shift, backslash, hash and at require AltGr. The $ and * are single keypresses though (where ] and ' are on QWERTY) , and normal braces are single keypresses too - but then [] and {} braces require AltGr.

Luckily Windows allows for quick shifting between keyboard configs with AltShift. I've got straight QWERTY, US-International and French lined up, which allows me to switch quickly between layouts to fit the job (AZERTY for typing French, QWERTY for typing English and Dutch and for coding, US-International for typing Dutch and French in certain conditions, and for coding with French comments). Adding Dvorak would be a bit too much, I think :)

--
Linux like wigwam. No windows, no gates, Apache inside.

[ Parent ]

John Ousterhout might be of interest (4.00 / 1) (#10)
by HidingMyName on Sat Nov 30, 2002 at 08:15:37 PM EST

John Ousterhout had RSI and put some notes on the web.

Pianists (4.00 / 1) (#12)
by MotorMachineMercenary on Sat Nov 30, 2002 at 09:17:03 PM EST

I had a slight problem with RSI, but then I read on the other site about how pianists avoid the same problem. All you have to do is make sure your wrists are straight and level with the knuckles. This is very easily achieved with a wrist-rest. It might be awkward at first, but believe you me, it really works. No use in fancy 'ergonomic' keyboards/mice.

After that, bye bye RSI. I also started using my left hand as my mouse-hand just for coordination purposes. Highly recommended.

--
"In a time of universal deceit, telling the truth is a revolutionary act."
-- George Orwell


What pianists did you talk to? (none / 0) (#28)
by rasactive on Sun Dec 01, 2002 at 08:32:12 AM EST

As somebody who has been taking piano lessons for ~7 years now, my piano teacher feels that he can't stress enough that the wrists always remain below the rest of the hand. The knuckles should be high, and the fingers should be curved.

The reason that piano players don't get RSI is because they strike piano keys different than one would strike a keyboard key, There is much more action in the knuckle than in the phalanges(correct word?) and the knuckle is much stronger. The wrists are also much more flexible (constantly moving up and down, rent a documentary on Evgeny Kissin if you want to see).

While your pianist friends gave you good advice about avoiding RSI, that's not necessarily how one plays piano well.

[ Parent ]
Still (none / 0) (#29)
by orestes on Sun Dec 01, 2002 at 09:27:06 AM EST

My teacher years ago (only took lessons for 6 months, but still :) said to never rest your wrists while you play. Maybe this same practice can help typists? I've found that supporting my hands with my arms, rather than the desk, feels much less awkward (but more tiresome). This would allow more freedom for your hands as a whole, as it does for a pianist.

[ You Sad Bastard ]
[ Parent ]
Applies to keys generally. (none / 0) (#46)
by static on Sun Dec 01, 2002 at 06:23:08 PM EST

I play a synth fairly frequently. It's a different action to typing, but the two complement each other. After more than a decade of both, I can physically see the wiriness in the muscles in my hands.

Wade.


[ Parent ]

Hmmmmm... (none / 0) (#66)
by inadeepsleep on Mon Dec 02, 2002 at 06:17:53 PM EST

Holding your wrists low may have worked for Glenn Gould, but I think the general consensus is that that's not a very bright idea.

And pianists *do* get strained muscles and tendons just like everyone else. But if you're going to produce a beautiful tone then you must be relaxed, so you always have the feedback of listening to yourself play.  I think that fits in with the main point made by the article writer pretty well.


[ Parent ]

At last. (4.00 / 1) (#17)
by acceleriter on Sat Nov 30, 2002 at 09:36:04 PM EST

My preference (some say fetish) for the good old IBM Model M "clicky" keyboard is vindicated.

I did learn to type on a manual--to this day I am brutal on keyboards, but my wrists don't hurt.

Older keyboards make a difference (none / 0) (#53)
by bdwebb on Mon Dec 02, 2002 at 02:40:58 AM EST

I also learned on a manual and also use the older IBM keyboards. I've been using IBM AT keyboards since 1985 (I keep 3 spares) and a Model M for those times when other people need the "newer" layout. I've never had keyboard-induced RSI, but I have twice had moderate problems due to some mouse-intensive projects. The theory that holding back the fingers rather than resting them on the device really rings true. I'm going to start taking my mice apart tomorrow and find a way to add extra resistance to the left and right buttons.

[ Parent ]
IBM AT keyboard rules (none / 0) (#60)
by Sloppy on Mon Dec 02, 2002 at 12:16:30 PM EST

I've been using IBM AT keyboards since 1985 (I keep 3 spares)
Kick ass! You're talking about the 84-key version, where are arrows and numerics are combined, right? That's what I use at work, too. Everyone in the office can hear me typing, but at least I'm never sore.

Hey, you ever notice a minor incompatibility between these beloved 84-key keyboards and XFree86 or Gnome or something? It seems like some text-entry widgets don't work with the arrow keys (and yes, my Numlock is off ;-). For example, in Galeon, in the widget where I'm entering this comment, the arrow keys work fine. But in the URL widget at the top, the arrow keys don't work.
"RSA, 2048, seeks sexy young entropic lover, for several clock cycles of prime passion..."
[ Parent ]

Good explanation (4.00 / 1) (#20)
by Big Sexxy Joe on Sat Nov 30, 2002 at 10:20:30 PM EST

I didn't understand the thing about muscles working in antagonistic pairs until you compared them to pairs of pnp and npn transistors.

I'm like Jesus, only better.
Democracy Now! - your daily, uncensored, corporate-free grassroots news hour
RSI and light keyboards (4.00 / 1) (#21)
by OldCoder on Sat Nov 30, 2002 at 10:34:27 PM EST

This idea is not brand new, as the existance of the research you cited underscores. When I had a bad RSI problem in the mid 1990's several of the doctors I talked to said that the simultaneous action of the opposing muscles and tendons was probably the cause.

Knowing (or suspecting) that didn't enable the docs to cure me though. Eventually, it got somewhat better, and I returned to work. Actually, what happened, was:

  1. I Rested my hands for a few years
  2. Went broke
  3. Saw 21 physicians
  4. Proved scientifically that it wasn't any of the diagnoses that docs suspected (carpal, cubital, RSD,...). Except that it involved "some myalgia" and "some tendonitis", which means that it hurt.
  5. Did pills, heat, massage, excercises, braces...
  6. I stopped smashing the keyboard.
  7. Changed from Sun keyboards to Microsoft "Natural".
  8. Found and cured an "unrelated" medical problem
  9. Got depressed and starting working my way through several anti-depressants.
  10. Became religious
The result is now I only feel the pain strongly when I am away from the keyboard.
Question: To which of the above should I attribute my partial cure?

Ye Olde Coder



--
By reading this signature, you have agreed.
Copyright © 2004 OldCoder

My guess would be (none / 0) (#39)
by Jel on Sun Dec 01, 2002 at 12:38:46 PM EST

Question: To which of the above should I attribute my partial cure?

Time? :)
...lend your voices only to sounds of freedom. No longer lend your strength to that which you wish to be free from. Fill your lives with love and bravery, and we shall lead a life uncommon
- Jewel, Life Uncommon
[ Parent ]

My experience with RSI (4.33 / 3) (#22)
by Spongebob on Sat Nov 30, 2002 at 11:02:17 PM EST

I've been using computers for the last 21 years. I've experienced all kinds of keyboards and mice one can possibly imagine. I had never had a single problem with RSI until a few years ago, when I woke up in the middle of the night with a pain in my arm that felt as "a pain in the bone". The pain is not very strong but enough to wake you up.

From that day on, I've been paying closer attention to my personal habits when it comes to using computers. Some conclusions:


  • Mice are EVIL: Most, if not all of my RSI was on the right arm. On my old Logitech the "angle" of the mouse curvature was too pronounced, forcing me to use the last degrees of finger movement to activate the buttons. Before I figured this out, I used the mouse on the left hand for a long time (today I'm ambidextrous when it comes to mice) :)

  • Keyboards: I like keyboards where a little bit of resistance is offered but no resistance at all after the initial threshold is passed. Examples of such keyboards are the old "clickly" IBM keyboards. A lot of modern keyboards offer physical resistance until the contact is made. This is bad.

  • Chair Height: Little differences in the height of the chair can ruin my day. Find a comfortable position and lock your chair inside a dungeon during the night.

  • It's not exacly RSI, but...: An interesting side note: My left "pinkie" went completely numb once. After a few days I decided to visit a neurologist. He asked for all kinds of exams, including one where your muscle's resistance to electricity is measured. Everything came back normal and yet he couldn't explain me what was going on. I moved on to another neurologist and explained the problem. He just asked to take a look at my arm and pressed hard on my elbow with his finger. Immediately, my finger got "number" than it was! He explained that it happens because a lot of people develop the habit of holding the head with the hand and rest the forearm in the table using the elbows. It took me over a year for the numbness to go completely away.

I hope it helps someone out there.

Regards


It's not exactly RSI but... (none / 0) (#34)
by tgibbs on Sun Dec 01, 2002 at 11:17:26 AM EST

I noticed that when I used my mouse my right thumb when numb. So I thought, OK, RSI, and switched my mouse to my left hand.

But when I moused with my left hand, my right thumb still went numb. Finally figured it out--when I was working intently (and mousing a lot), I had developed a habit of leaning forward and craning my neck to look at the screen. The problem wasn't in my wrist at all, it was in my neck.

Six weeks of wearing a foam collar, retraining myself to sit up straight, and taking anti-inflammatories, and the problem went away permanently.

[ Parent ]

wow mom was right (none / 0) (#43)
by tzanger on Sun Dec 01, 2002 at 03:22:49 PM EST

He explained that it happens because a lot of people develop the habit of holding the head with the hand and rest the forearm in the table using the elbows.

So not only is elbows on the table bad manners, it's bad for your health!



[ Parent ]
How to ignore the mouse (4.66 / 3) (#23)
by Blarney on Sun Dec 01, 2002 at 12:16:22 AM EST

Most desktop environments allow the vast majority of computer use to be performed without using a mouse at all. If you run Photoshop you'll be mousing all over the place, but quite often you can manage to do everything you need with keyboard shortcuts. That rotten little rodent is a RSI torture device, but most users can cut their usage of the mouse by an order of magnitude with a little effort, and will find that computing is faster and more comfortable without it.

Even learning basic shortcuts can keep your hands off the mouse most of the time. Don't mess with the taskbar or click around framed windows - use Alt-Tab and Control-Tab whenever possible. Don't click on GUI controls - Tab and Shift-Tab around. If you need to move a window or minimize it, don't drag it - Alt-Space (Windows) or Alt-F3 (KDE) and select from the menu; Alt-Space-N is much easier than finding the stupid little minimize button with the mouse. Don't use Netscape 4, ever - because tabbing on web forms is flakey - use IE or Mozilla instead. Learn the most common menu shortcuts like CTRL-C CTRL-V CTRL-S, and Alt-key your way through menus instead of mousing. And finally, don't buy an Apple! Now you can live a happy, mouseless life.

I'm expecting lots of pro-Apple flames. This is gonna be great!

Rats (4.50 / 2) (#26)
by Alan Crowe on Sun Dec 01, 2002 at 05:01:21 AM EST

I would like to get a "rat", that is a large mouse that I can put on the floor, and operate with my foot. Then I could leave my hands in the home position on the keyboard.

I've tried putting a mouse on the floor. I told the mouse demon that the mouse had four times as many dots per inch as it really did. This got the sensitivity about right. However, I couldn't work the mouse buttons with my toes. I think this is because the buttons are too close together, and too light in action. If they were spaced for toes, one for the big toe, one for the middle two toes, and one for the outer two toes, and had a suitably heavy action, I think I could learn the dexterity required in a few hours.

When I searched for rats two years ago, all I found was www.footmouse.com who charge for $290 for a no button shoe-mouse, with a seperate, single foot switch. This morning, Googling gets me lots of interesting hits to follow up.



[ Parent ]
More natural for feet would be.. (none / 0) (#38)
by Jel on Sun Dec 01, 2002 at 12:33:37 PM EST

Wouldn't it make more sense to properly adapt the design to feet?

Feet rock back and forward quite naturally, so why not use that?  Just put the primary button at your toes, and the secondary at your heel.  Third?  Hell, I dunno, jump on it or something! ;)

...lend your voices only to sounds of freedom. No longer lend your strength to that which you wish to be free from. Fill your lives with love and bravery, and we shall lead a life uncommon
- Jewel, Life Uncommon
[ Parent ]

Don't forget .... (none / 0) (#41)
by HypoLuxa on Sun Dec 01, 2002 at 03:05:49 PM EST

... that you have two feet. Forward left, back left, forward right, back right should be plenty of hot button action for you.

--
I'm guided by the beauty of our weapons.
- Leonard Cohen
[ Parent ]
Don't forget your toes (none / 0) (#56)
by Alan Crowe on Mon Dec 02, 2002 at 08:42:42 AM EST

There are four layers of muscles on the underside of the foot, dedicated to flexing the toes, and yet more muscles to extend them.

Now that the GUI has evolved into a monster, requiring the user to have three arms, two for the keyboard and one for the mouse, it seems very natural to try to exploit the potential of toes as extra fingers



[ Parent ]
bbkeys (none / 0) (#27)
by evilpenguin on Sun Dec 01, 2002 at 08:22:31 AM EST

If you're using blackbox, you can set up bbkeys to do all the same (and more).  The way I have it set up:
"F-n + Alt" switches to workspace n
"Alt + Tab" and "Alt + Shift + Tab" switches between windows
"Ctrl + L/R" arrows to switch to the previous/next workspace
"Control + Shift + h/j/k/l" to switch to previous/next workspace and previous and next window
"Ctrl + Alt + [arrow key]" moves ("nudges") a window in that direction
"Ctrl + Shift + [arrow key]" resizes windows
"Ctrl + Shift + Enter" shades/unshades a window
"Ctrl + Shift + m" maximizes a window
"Ctrl + Shift + f" raises a window (bring to front)
"Crtl + Shift + b" lowers a window (push back)
"Ctrl + Alt + c" closes a window
"Ctrl + Shift + d" brings up a new Eterm

This yet another reason why I love blackbox.  If anyone's interested, I'll post the .bbkeysrc file that does all this.  It's incredibly fast and useful once you get the hang of it.
--
# nohup cat /dev/dsp > /dev/hda & killall -9 getty
[ Parent ]

I'd definitely be interested (none / 0) (#31)
by Anonymous 7324 on Sun Dec 01, 2002 at 10:17:37 AM EST

in seeing a copy of that, if you don't mind. Thanks! :)

[ Parent ]
Lets hope scoop doesn't mangle this (none / 0) (#33)
by evilpenguin on Sun Dec 01, 2002 at 10:45:37 AM EST

.bbkeysrc
-------------------
# Workspaces
KeyToGrab(F1), WithModifier(Mod1), WithAction(Workspace1)
KeyToGrab(F2), WithModifier(Mod1), WithAction(Workspace2)
KeyToGrab(F3), WithModifier(Mod1), WithAction(Workspace3)
KeyToGrab(F4), WithModifier(Mod1), WithAction(Workspace4)
KeyToGrab(F5), WithModifier(Mod1), WithAction(Workspace5)
KeyToGrab(F6), WithModifier(Mod1), WithAction(Workspace6)
KeyToGrab(F7), WithModifier(Mod1), WithAction(Workspace7)
KeyToGrab(F7), WithModifier(Mod1), WithAction(Workspace8)

# Alt_L + Tab window switching, a la Windows
KeyToGrab(Tab), WithModifier(Mod1), WithAction(NextWindow)
KeyToGrab(Tab), WithModifier(Mod1+Shift), WithAction(PrevWindow)

# Workspace navagation with arrow keys
KeyToGrab(Right), WithModifier(Control), WithAction(NextWorkspace)
KeyToGrab(Left), WithModifier(Control), WithAction(PrevWorkspace)

# Vi-style workspace manuvering
KeyToGrab(h), WithModifier(Control+Shift),  WithAction(PrevWorkspace)
KeyToGrab(l), WithModifier(Control+Shift),  WithAction(NextWorkspace)
KeyToGrab(j), WithModifier(Control+Shift),  WithAction(PrevWindow)
KeyToGrab(k), WithModifier(Control+Shift),  WithAction(NextWindow)

# Push windows around
KeyToGrab(Up), WithModifier(Control+Mod1), WithAction(BigNudgeUp)
KeyToGrab(Down), WithModifier(Control+Mod1), WithAction(BigNudgeDown)
KeyToGrab(Left), WithModifier(Control+Mod1), WithAction(BigNudgeLeft)
KeyToGrab(Right), WithModifier(Control+Mod1), WithAction(BigNudgeRight)

# Resize windows
KeyToGrab(Up), WithModifier(Control+Shift), WithAction(VerticalDecrement)
KeyToGrab(Down), WithModifier(Control+Shift), WithAction(VerticalIncrement)
KeyToGrab(Left), WithModifier(Control+Shift), WithAction(HorizontalDecrement)
KeyToGrab(Right), WithModifier(Control+Shift), WithAction(HorizontalIncrement)

# Window positioning commands
KeyToGrab(Return), WithModifier(Control+Mod1), WithAction(ShadeWindow)
KeyToGrab(Return), WithModifier(Control+Shift), WithAction(ShadeWindow)
KeyToGrab(m), WithModifier(Control+Shift),  WithAction(MaximizeWindow)
KeyToGrab(f), WithModifier(Control+Shift),  WithAction(Raise)
KeyToGrab(b), WithModifier(Control+Shift),  WithAction(Lower)
KeyToGrab(c), WithModifier(Control+Mod1), WithAction(Close)

# The most common reason I bring up the menu -- get more Eterms
KeyToGrab(e), WithModifier(Control+Shift), WithAction(ExecCommand), DoThis(Eterm -O --tint `randcolor`)
KeyToGrab(d), WithModifier(Control+Shift), WithAction(ExecCommand), DoThis(Eterm -O --tint `randcolor -l`)
-------------------

'randcolor' is a little C program I wrote to give me a random hex triplet to use as the transparency tint (the '-l' flag assures a dark tint for better contrast).  Eye candy good.
--
# nohup cat /dev/dsp > /dev/hda & killall -9 getty
[ Parent ]

Thanks much! (n/t) (none / 0) (#42)
by Anonymous 7324 on Sun Dec 01, 2002 at 03:16:02 PM EST

no text

[ Parent ]
MacOS is best for keyboard shortcuts. (none / 0) (#30)
by mr strange on Sun Dec 01, 2002 at 10:15:17 AM EST

Windows' keyboard shortcuts are all over the place. This is due to conflicts between supporting old DOS-style shortcuts and the MacOS ones they inherited when Office was ported over from that platform.

X-windows applications' shortcuts tend to be all over the place as well. How to I close an application? Ctrl-Q, Ctrl-X, Alt-Q, Alt-X, Alt-F4? At least X-windows apps tend to be highly configurable, so a determined user can make their environment consistent if they want. Most users (myself included) are not so determined.

MacOS on the other hand, has a large number of the most common actions fixed to defined keyboard shortcuts. Copy, paste, quit, find... etc. etc. are always the same in every application. This was by design (and decree) from the earliest days of Macintosh. Power-users might miss the ability to change the key-bindings, but for most users, it is this consistency that makes the shortcuts reliable and therefore usable.

intrigued by your idea that fascism is feminine - livus
[ Parent ]

Mac (none / 0) (#32)
by bigbtommy on Sun Dec 01, 2002 at 10:20:00 AM EST

C'mon it's not that bad. Load on OS X, and use CLI via Terminal.app (or as some divvy Mac users call it - the 'matrix' interface) or login as >console . The only annoying thing is menus - you can't access them via Alt like you can in Windows. Simple answer? Learn the key commands for your most frequently used key commands, and use something like QuickKeys to set up your F keys to do various useful tasks.

It's the only machine I've found that's capable of running Office, Photoshop etc. as well as cronning, grepping and running daemons to my hearts content.
-- bbCity.co.uk - When I see kids, I speed up
[ Parent ]

Mac Menus (5.00 / 2) (#37)
by DJBongHit on Sun Dec 01, 2002 at 12:05:49 PM EST

The only annoying thing is menus - you can't access them via Alt like you can in Windows.
Head over to the keyboard control panel in System Preferences and turn on full keyboard access. This gives you full access to everything with the keyboard, including menus, the dock, toolbars, and utility windows. You can even turn full keyboard access on and off with a keystroke (Ctrl-F7) if the shortcuts are interfering with another app.

~DJBongHit

--
GNU GPL: Free as in herpes.

[ Parent ]
Faster. (none / 0) (#35)
by NFW on Sun Dec 01, 2002 at 11:29:45 AM EST

Way faster.

Generally speaking, reaching for the mouse while using a computer is like swerving around a pothole while driving. Sometimes you have to, but you get places faster with well-maintained roads and well-thought-out user interfaces.

Graphical applications and 'drag' gestures are exceptions to this rule (and not necessarily the only ones), but when it comes to invoking simple commands, the keyboard has more bandwidth (approx. 50 times more buttons) and less latency (no need to carefully position a virtual pointer over a virtual button, just keep your hands on home row).


--
Got birds?


[ Parent ]

I still use the mouse a lot end editing text/codin (none / 0) (#47)
by SoupIsGoodFood on Sun Dec 01, 2002 at 08:25:24 PM EST

One point. I'm a web designer and and spend a lot of time at the keyboard in code etc. I still find I use the mouse a lot since I'm always jumping around to different places in the code. Using the keyboard to jump to too slow most of the time.

Any suggestions for that? How do other people find it using a mouse in this way?

BTW. I've used both OS X and OS 9. And while they may still be laking a few areas in regards to keyboard shortcuts. I still find that the application's shortcuts are usally better and more consistant than they are in the windows world.

[ Parent ]

Coding (none / 0) (#62)
by lb008d on Mon Dec 02, 2002 at 02:52:58 PM EST

Using the keyboard to jump [is] too slow most of the time

All I can say is this - learn to use a text editor that doesn't use the mouse at all and learn it well. I'll leave it as an exercise to the reader to pick one.

"Kuro5hin: politics and pretension, from the $3,000 leather recliners on the hill overlooking the trenches."DarkZero
[ Parent ]

Find a really good code editor (none / 0) (#72)
by Gromit on Wed Dec 04, 2002 at 07:25:10 AM EST

I use Multi-Edit (www.multieditsoftware.com), which you can customize quite dramatically. One way I have it customized is that Alt+1 through Alt+9 drop bookmarks which I can jump back to with two keystrokes. I also coded up a VI-style command mode (entirely in the macro language of the editor), so I find moving around in code a dream without a mouse.

--
"The noble art of losing face will one day save the human race." - Hans Blix

[ Parent ]
Not a pro-Apple flame (none / 0) (#55)
by claudius on Mon Dec 02, 2002 at 08:25:56 AM EST

...but an observation.  I find the one-button mouse that comes with newer Macs to be quite good in terms of ergonomics.  One-button mousing, where the entire surface of the mouse is the mouse button, allows one to operate the mouse while keeping all one's fingers in contact with the mouse pad in a neutral, low-stress position.  


[ Parent ]
mac (none / 0) (#57)
by calimehtar on Mon Dec 02, 2002 at 09:05:19 AM EST

If you're referring to the Mac's lack of keyboad access... you should know that every single one of the examples you mention has a system-wide equivalent on any mac system higher than 8 (I didn't use lower than 7 much, could be there too). Command-M to minimize, Command-H to hide, Command-tab switches applications (command-tilde switches windows), tab switches text fields in forms.

Of course there are other things which don't work in Mac OS by default like tab to switch to the cancel button. I'm not sure if this has been added or not.



[ Parent ]
My Setup (5.00 / 2) (#24)
by Talez on Sun Dec 01, 2002 at 02:57:53 AM EST

I have a fairly recent IBM PS/2 keyboard that I scabbed off a P75 ages ago. I can safely rest my fingers on the keys without pushing them enough to make contact. I've always used keyboards using this method and I haven't had RSI at all over the past 15 years that I've been using a PC.

Secondly is the mouse. I always put my palm over the mouse and rest my fingers over the buttons. Using this method I can just roll my finger to the side to click or I can bring my knuckle up to push down on the button. Either way is fine for me.

The biggest problem for me has been shifting to a wheel mouse. Up until about 6 months ago I was still using my aging (it was 5 years old) Logitech PS/2 ball mouse that I bought for 25 bucks after desiring a real mouse to play FPS games with. I still havent managed to rest my fingers properly. Out of habit, I find myself using my right mouse button finger over the the wheel. I am slowly weaning myself off this habit.

At any rate, I've always used a Logitech mouse so I've always recommended them. I've never used their keyboards but I am looking forward to buying one of the elite keyboards possibly after Christmas.

Si in Googlis non est, ergo non est

I use a touchpad instead of a mouse... (5.00 / 1) (#40)
by dagg on Sun Dec 01, 2002 at 02:08:29 PM EST

Several years ago, I started to feel the strain of using a mouse all day. I never sought any medical treatment for the strain, but it was slowing down my work. The pain was at its worst when I used a mouse. At some point, I noticed that I never felt the pain when I used the touchpad on my laptop. That's when I decided to use a touchpad nearly exclusively. My pain quickly dwindled to nothing.

Now the only time I feel wrist strain is after I've played Super Mario too long :-).

--
Find Your Sex

--
Find Yer Sex Gateway
Amen brother! (none / 0) (#73)
by meaningless pseudonym on Thu Dec 05, 2002 at 03:19:18 PM EST

Everyone at work thinks I'm strange but I much prefer a touchpad and moved after being kept awake at night with shoulder pains that I'm almost certain were caused by mice. Now I almost never have any problems.

Honestly, I believe that a well set-up touchpad (hint - acceleration and tap sensitivity are more critical than with mice) is significantly superior for GUI work than a mouse. I mean, look at the angle you have to hold your arm at and think of the penalty while you reorient your body on the new device when you switch.

Anyway, rant over :-)

[ Parent ]

Gaming (none / 0) (#44)
by vile on Sun Dec 01, 2002 at 03:34:19 PM EST

I tend to use both the keyboard and mouse at long intervals while gaming. I tend to use WASD+Space for movement and the mouse for looking and firing.

After several hours of playing in this fashion, my left hand starts to feel strained. Sometimes, I continue playing. I also notice differences when I shift my wrist position, as a few posters have commented on.. but no matter what I do, I don't think I'll ever be able to get rid of this effect if I continue the WASD/Space style.

I also think part of the cause is the small distance that my fingers move within, repetitively. I can type normally for 24+ hours without these effects.

Does anyone have any suggestions on what else I could try?

~
The money is in the treatment, not the cure.
I learned typing... (4.50 / 2) (#45)
by failrate on Sun Dec 01, 2002 at 04:16:34 PM EST

on a Woodstock mechanical typewriter. That required some serious development of key-striking strength. As a result, I pound on my keyboard. It has been commented that I have some of the worst keyboarding style ever seen. hee hee. However, I don't have RSI or carpal tunnel, because I frequently use yogic hand stretches, as well as other means of keeping my wrists supple (insert sin of Onan joke here). I have also found using Asian "meditation balls", or golf balls or billiard balls in the same capacity, to be quite relieving.

However, I often accidently press mouse buttons when I'm only attempting to rest my fingers...
Voodoo Girl is da bomb!
<aol>Me Too!</aol> (none / 0) (#54)
by wiredog on Mon Dec 02, 2002 at 08:10:48 AM EST

I learned typing on my father's vintage 1950 mechanical typewriter. I replace keyboards every couple of years. For some reason, they seem to wear out.

More Math! Less Pr0n! K5 For K5ers!
--Rusty

[ Parent ]
the cause -- my opinion (4.00 / 2) (#48)
by tealeaf on Sun Dec 01, 2002 at 08:28:45 PM EST

I highly agree with the theory in the article.  I had the symptoms a while ago and was paying very close attention to what was going on.  Indeed, I noticed during high-speed, high-tension typing bursts the hands tend to spaz out, which is exactly two opposite muscles fighting each other.  That definitely contributes to pain.  There are also other factors, such as mental state.  Example: just thinking of RSI can bring on intense pain when there was no pain before.

Tips to avoid and to cure RSI:

  1. Check your mental state.  Don't channel your stress into your hands and into your typing.  Feeling stressed?  Type slower or avoid typing when stressed.
  2. Don't pound like an insane lunatic.  Key only needs 35g to activate, and that's all you should apply.
  3. Don't type faster than fast.  There is a fast speed at which you are still comfortable and there is a speed slightly above that which you can achieve thanks to partial spazzing out and stress.  Avoid that 5% speed gain at the expense of mental and physical balance.
  4. Excercise your hands.  Get a grip thingy, preferrably a rubber ring you can squeeze, or if you are strong enough, use the tennis ball.  Squeeze it 30-50 times each day.  Don't overdo it.
  5. Take a short break once in a while.
  6. Stretch your hands gently.  Again, do NOT overdo it!  You can make it worse by trying too hard here.
  7. Eat healthy.  If you eat crap, try to upgrade to better food.  Body needs nutrients to repair.  Nerves need nutrients too.  I am sure stress depletes something that needs to be replaced.  You can't go wrong with a healthy diet that gives you everything.  (unless you overeat).
  8. SLEEP!!  Sleep 8 hours every day.  If you want to make your RSI worse, continue to sleep 1 hr a night.
Overall, mental stress and physical stress is what you need to avoid.  Remember, you can't control stress.  What you can do is avoid getting stressed out in the first place.  If you are getting stressed out and you think you can "manage" or "control" that stress, you are insane.  Once you are stressed out, it will find an outlet by killing or hurting you.

8 hrs might be too much (none / 0) (#64)
by ph0rk on Mon Dec 02, 2002 at 03:51:16 PM EST

no urls, (well, okay, here's one http://www.mindbodyhealth.com/sleep1.htm) but i have read in numerous places 8 hours of sleep might just be a tad too much.

i hover around 6.5-8, depending.
[ f o r k . s c h i z o i d . c o m ]
[ Parent ]

Bull (none / 0) (#68)
by Cro Magnon on Tue Dec 03, 2002 at 10:22:37 AM EST

I don't buy that! People vary, and while some people can get by with 4 hours sleep, for others, 8 might not be enough. And I think it's safe to say more people are getting too little sleep than too much.
Information wants to be beer.
[ Parent ]
from what (2.50 / 2) (#50)
by auraslip on Mon Dec 02, 2002 at 12:28:11 AM EST

I've read of the comments here, It seems to me that much of the problem is caused by mice, and that not using mice goes a long way to helping.

If windows was not only taught, but designed(today the commands seem to be used just for the situations lacking a mouse) to be used as a mouseless system (with the mouse being used for other things, photoshop games) it would be much quicker, and much better.
Since it is obvious that microsoft would not force people to take this route (many people have trouble learning to use a mouse, and it's almost as simple as a nipple! point and click) I will leave it up to the Linux programers to heed my suggestion so maybe one day when OS becomes a viable alternative we'll all be extra happy.
Of course, they already have done this, but minus the GUI part.

124

Amazingly... (5.00 / 1) (#71)
by Gromit on Wed Dec 04, 2002 at 07:13:56 AM EST

...I find myself defending Microsoft on this, which -- trust me -- is incredibly rare. From the beginning, you couldn't use a Mac without using a mouse. You couldn't select commands from the menu (unless they had hotkeys, %X etc.), but Microsoft put in their guide to writing Windows programs that the entire system must be usable without a mouse barring some specialist reason why you must have one (e.g., painting software and the like). (Many, many years later -- we're talking '94 or thereabouts -- Apple improved things so you could finally do the equivalent of Windows' pressing just the Alt key [or F10] and browsing the menus with the keyboard's arrow buttons.)

Sadly, Microsoft don't seem to have managed to keep going with that, and of course web browsers (and web page designers) are notoriously terrible on this point, but it was in their requirements for application certification for quite a long while, possibly even still is. But people still use mice because they perceive it's much easier.



--
"The noble art of losing face will one day save the human race." - Hans Blix

[ Parent ]
i'm dealing with an RSI... (none / 0) (#52)
by krkrbt on Mon Dec 02, 2002 at 01:54:16 AM EST

...and your description is definitely on the right track.  Not complete, but you're getting there.  The best info I've found on 'getting better' comes from Walt Stoll's website at http://www.askwaltstollmd.com/ - the thing he advocates most (for just about everything :) is "skilled relaxation" [SR].  SR is like meditation - relaxing the body and calming the mind.  This "bracing" you mention in the article is apparently the cause of many other health maladies.  

When you've got some "bracing" going on it can be very difficult to relax completely, especially if it's something you've never done before.  My experience exactly.  (This "relaxation" walt talks about on his site is when it feels like your body is totally asleep [think full-body novacain], and yet your mind is awake & concious.)  Walt recommends some type of body work - Rolfing, trigger point therapy, etc, to help make getting started with the SR easier.  I had an excellent experience with trigger point therapy [aka "Myofascial Release"] one spring break, when combined with a week-long total respite from the keyboard.  Unfortunately, skool is thousands of miles away from the best trigger point person I've managed to find, and I didn't yet realize what it was I needed to do to get and stay better...  Why it is I'm not better yet is kind a long story, one that i'm not willing to get into now, while I'm all sore from typing damn papers for fricking damn classes that I don't really care about other than being 1 week away from finishing the last semester at this damn expensive school for a damn "degree".  [anyone care to venture what I believe is the real source of my RSI affliction?]


Not so sure... (4.00 / 1) (#65)
by Fon2d2 on Mon Dec 02, 2002 at 04:00:51 PM EST

I really like this theory for the cause of RSI but I don't think it's the full picture. I always thought the reason for keeping the wrist straight was to prevent rubbing inside the carpal tunnel. I can't remember what passes through it, if it's nerves or tendons, but I do remember that it is very narrow and that any inflamation is very bad. Also, keeping the wrist straight (whether you are holding your wrists up or using a wrist pad), like you said, frees your extensors from extranious work. I use wristpads for both the mouse and the keyboard, however I do notice strain from the mouse. Never with the keyboard. After one game of minesweeper (great game for mouse induced RSI) I can feel the fatigue in the extensor of my right index finger. Now I don't imagine that I'm flexing my extensors the whole time I'm using the mouse but muscle tension can be a very subconcious and unnoticed thing. Basically I could have some bad habits, some bad posture, a bad ergonomic setup, or any combination of the three. Now constant tension in the extensor muscles seems an obvious enough reason for RSI but extensor fighting flexor muscles doesn't seem so obvious, until I think about trying to play piano very quickly. One of the things about piano however is that if you feel strain, then you know that either you are playing it too fast or playing it wrong. If you have the rote motor skills to control your fingers at a particular speed then you can play at that speed for a very long time. When you go above that the muscles easily start to conflict. It's obvious what's happening there, but that seems to be for a different reason than you would get for a normal keyboard. With the piano, I'm trying to play faster than I can create coherent signals for my muscles, so the tension and timing in the muscles are all wrong. Some of the same happens when I type, but still, that's due to bad typing skills or mental lapses. I wonder if there is any of the kind of the internal stress you describe when people have their chairs the proper height, have the wrists held in the proper position, and type at or below their typing speed.

Both nerves and tendons go through carpal tunnel (4.50 / 2) (#67)
by upper on Tue Dec 03, 2002 at 02:03:34 AM EST

I always thought the reason for keeping the wrist straight was to prevent rubbing inside the carpal tunnel. I can't remember what passes through it, if it's nerves or tendons, but I do remember that it is very narrow and that any inflamation is very bad.

The carpal tunnel contains both nerves and tendons. The tendons are the flexor tendons for fingers and thumb. The nerves are responsible for feeling in most of the hand. And the carpal tunnel is a confined space -- bone most of the way around and inelastic ligament the rest of the way.

If tendonitis (inflamation of/around a tendon in response to minor injury) develops in those tendons, they swell. And the carpal tunnel can't expand -- it's bone most of the way around and inelastic ligament the rest of the way. The result is pressure on the nerves, sometimes leading to numbness in the hand. That's what carpal tunnel syndrome is.

[ Parent ]

Thank you (none / 0) (#69)
by Fon2d2 on Tue Dec 03, 2002 at 03:51:12 PM EST

That was very informative.

[ Parent ]
laptop keyboards and mice (none / 0) (#76)
by churchillian on Sat Jan 04, 2003 at 11:29:34 PM EST

I think that (da) some keyboards are better than others. I have a theory that laptop keyboards are actually not bad for you as long as they are large enough and comfortable enough. For instance it forces you into using a wrist rest which is great for your hands and you can really rest your arms on the computer. I also think that the mice are a lot better. I have an IBM Thinkpad so I use what they call a track point (ie nipple thing), and it actually works really well. But also (as I read in a few reviews above) the regular laptop mouse pads are also not too bad ergonomically. The mouse it seems is one of the greatest problems. This is probably because of having to use small movements in your wrist and forearm - muscles not designed or used very often for this sort of task. Using a keyboard is not so far from the abilities of fingers therefore it tends to be mice that cause the most RSI (sorry no statistical evidence - I'm not a physicist or something). My only real problem with using a computer for a long time is when I paly something like minesweeper - the computer user killer - which I love. It hurts my eyes and causes them to burn. I don't know why. Any advice? I probaby should get some glasses, but I'm not sure that's everything.

The Cause of RSI | 76 comments (64 topical, 12 editorial, 1 hidden)
Display: Sort:

kuro5hin.org

[XML]
All trademarks and copyrights on this page are owned by their respective companies. The Rest 2000 - Present Kuro5hin.org Inc.
See our legalese page for copyright policies. Please also read our Privacy Policy.
Kuro5hin.org is powered by Free Software, including Apache, Perl, and Linux, The Scoop Engine that runs this site is freely available, under the terms of the GPL.
Need some help? Email help@kuro5hin.org.
My heart's the long stairs.

Powered by Scoop create account | help/FAQ | mission | links | search | IRC | YOU choose the stories!