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Computers and Carpal Tunnel Syndrome Studied
pioneer writes "An article on MSNBC.com reports that a Danish study has found that computer use is not a significant risk factor for carpal tunnel syndrome. Not sure about you, but I spent a lot of time learning dvorak and kinesis to prevent just that... the 'inevitable' onslaught of RSI/carpal tunnel/etc."
...the wrist can hurt for many reason.
But what about that other activity that is associated with a man, and his wrist. Is it a significant risk factor?
I'm asking....for a friend.
Mike
Tell this to me Captin Jello! I got the Hook to replace my hand loss from Carpal Tunnel. And I lost an Eye from it too. Arr!
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
My opinion is that the younger you started the less likely you are to have problems. I've been at a keyboard since before 10yrs old, and now, over 30, I don't have any problems at all, either eye sight or wrist/hand related. No special keyboards, no left/right hand mouse switching.
M@
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I've been using computers for heavily decades and I've never had any real effects from it all. Ow! Now only if that tingling in my hands would go away...
My journal has hot
Actually the article says it's a Danish study ...
...both of my wrists are cramping up. The more I type, worse my wrists get. Sadly, I'm a programmer. That doesn't help things. I cannot agree with a study that tries to disassociate repetitive motion with RMI. That's just bologna.
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that since I've been using computers since 1st grade (I'm now out in the world working), that it was a load of crap.
Also, my eyesight hasn't gotten worse, it's better.
Oh well, I wonder how long until that study comes out.
But I know for a fact that a 10 hour playstation session can cause me to develop some awful pain in my fingers.
Is Nintendo thumb an accepted medical term yet?
As far as I can tell carpal tunnel syndrome occurs mostly in people with desk jobs that involve computers, not industrial work, which was mentioned as a possible cause in the study. If it's not keyboard use then what is it?
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If the article header is accurate, then Pioneer should be informed that carpal tunnel syndrome is only an INSTANCE of RSI, and the two are not equal. It is, in fact, still possible that every single other type of RSI has computer use as a significant risk factor and not contradict this study.
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I don't know about you, but my computer usage averages about 10 hours a day. However, I don't know if I actually type for 7 hours out of the ten, after factoring in meetings and other productivity boosters.
I worry more about my eyes than wrists. I may not be typing 100 wpm constantly, but I am looking at my monitors even when not typing.
Okay. Either I misread it the first time over, or the editor in charge already changed it (I hope the latter, otherwise eye sight problems might have been induced by severe monitor use)
:)
But to reply on the matter at hand (no pun intended), any sort of work which forces you into the same type of repetitive movements or the same position for hours on end, has serious health repercussions. If this study 'proves' (for as far as you can do that in a statistical study) that computer keyboard use isn't the primary cause for CTS, then it's still a useless study. If it would have been a study to what *does* cause these kind of problems, it would be of a lot more use to the generic population of computer users.
I'll wait for this study to appear before drawing any conclusions. On the base of this article, any comment would be straining for significance. It doesn't describe the testing methods, it doesn't describe the age group, it doesn't describe the previous work, etc, etc.
On just this article, I don't think anyone can make any intelligent comments (and I'll include myself in that as well
Mad.
Coz eternity my friend, is a long *ing time.
If this is the case, I wonder how it came to be that computer use was associated with RSI/carpal tunnel.
I had always heard (can anyone verify this?) that it was mouse use, in particular with scroll-wheels, that was the main offender.
but I spent a lot of time learning dvorak and kinesis to prevent just that
Maybe if he'd put some more time into telekinesis he'd still have a useful skill.
This is the NFL, which stands for "Not For Long" if you keep making those bulls*** calls.
Computer use is no more a cause for repetitive stress injuries than any other activity. The difference is that people don't seem to stop for a while when their bodies tell them to.
I've been keyboarding long days for 26+ years now (and "mousing" since 1984). When I start to feel a little cramped, I stop for a few minutes. No carpel tunnel injuries.
Likewise, my vision hasn't changed over the same period, for the same reason. Eyes get tired? Stop. Look around (at a distant object). Close them for a minute.
Repetitive stress injuries are self-inflicted wounds. The psychology behind the activity would be more interesting to read about, but I haven't seen any articles on that subject.
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Just like most of you, I've been typing on computers for years. I've never experienced any sort of Carpal Tunnel due to typing. This doesn't mean I'm immune however. Last year I painted the interior of my entire house and suffered severe wrist pain and numbness. My wife is a Physical Therapist and diagnosed me with Carpal Tunnel. For me anyway, computer keyboards are harmless.
The researchers said they did find an association between use of a mouse for more than 20 hours a week and a slightly elevated risk of a possible problem but no statistically significant association with keyboard use.
So mouse usage is a problem, but the keyboard isn't. Guess I should stop playing Battlefield 1942 at work then.M-x show-mappings
C-M-g pain
C-M-G agony
C-M-T paralysis
Look at the inventors of *emacs: Stallman - CTS. Gosling - CTS. Zawinsky - weird. Wing - bald.
In the absence of "emacs peddles", the confirmed emacs user is doomed (dooomed).
(in next week's exciting episode: "Perl and your spermcount - the shocking truth").
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Typing doesn't cause carpal tunnel, or any other RSI. Improper wrist positioning will do it, though. "Traditional" touch-typing on a QWERTY keyboard (fingers on the home row, ASDF JKL;) crimps up your wrists and is just bloody unnatural.
I've been typing since I was five--I'm twenty-five now. I type at ~100WPM. Because I'm self-taught, I don't use the traditional touch-type method. When I type, my hands are at about a 45 degree angle to the keyboard; if I had a "home row", it would be something like QSDC MKLP. I hit whichever key with whichever finger is closest. My wrists stay straight and uncrimped.
I type multiple hours per day, every day, and I don't suffer fatigue, carpal tunnel, RSI, or any of that other business. My touch-typing coworkers walk around with braces on each wrist, and gingerly ease themselves down in front of split-key ergo keyboards and start wincing when they have to type for more than a few minutes.
Keyboarding doesn't cause RSI. Traditional, wrist-crimping touch-typing causes RSI.
While still in college (10+yrs ago) I developed CTS in both wrists while working on a landscaping crew. I've found it doesn't slow me down at the keyboard now-a-days ... I'm a fulltime programmer
l8r
Try telling this to the people (about 6) I know who have had supportive treatments and/or operations.
It has occured to me that all these people are females in their 40's or 50's, who are generally receptionists, keying in data whilst on the phone.
I've had a mild case & switching to one of the specialist keyboards has helped. I use a Fingerworks TouchStream ST - excellent but it takes some getting used to, is a right old pain if you work in the UK and need to use the £ sign (character map etc etc).
The mouse thing is interesting - I have found that most problems occur in the hand that isn't using the mouse, as it's being lifted of the keyboard whilst mousing.
But I wore the juice
With all due respect to my computer-using brethren, I can entirely understand this and have long suspected the same.
Carpal-Tunnel and RSI were originally diagnosed in women who worked at "sweatshop" textile factories in the early part of the industrial revolution. Sewing is WAY harder on your hands than typing, and so it probably ran rampant in that environment. But there was almost no treatment; women were by and large told to "suck it up" and stop complaining, because it was "just" pain afterall, it's not like they broke anything.
It wasn't until millions of white men started working with keyboards and a VERY SMALL percentage of them got RSI, that it became worthy of national attention. And so now, if you get diagnosed with RSI, you can get disability pay, early retirement, or at least many ergonomic adjustments to facilitate your recovery... IF you're white.
One of the groups who suffer RSI at a much higher rate than computer users: meat packers. Today's meat packing plants run 2-3 times faster, sometimes more, than their historical counterparts, and some cutters have to slice through 60-80 pounds of meat over 100 times an hour. I promise, this will burn out your wrists WAY faster than writing an ActiveX module. But most meat plant workers are Hispanic, and/or non-English speakers. They get $9 an hour, minimal benefits, and, like women in textile factories of old, are usually told to shut up and quit if they don't like it when their wrists are in searing pain.
So, by and large CT/RSI is an affluent white excuse to complain about jobs we aren't "satisfied" with. The people who are truly suffering from these conditions are largely ignored and always have been.
I've been typing since I was about 6... at age 20 or so I began to experience symptoms of a RSI, tingling fingers, burning pain in the wrist, etc etc. So I took some steps. I got an ergonomic keyboard for home, and those gel pads that supposedly help you keep your wrists up. The tingling got worse and worse over the next few weeks. What seemed to hurt the worst was actually resting my wrist on the pad while typing. So I stopped. I began typing by keeping my hands in the air at all times, keeping the backs of my hands level with my forearms, and letting my fingers fall down to the keyboard rather than reaching out toward it. It looked weird, but it was the only way I could type without wincing.
The pain was gone within 2 weeks. The last the of tingling faded away (except in the pinky of my right hand, which seems to be related to mouse use) a month or so later. As long as I keep up this spidery-looking typing style, my hands don't hurt.
Might be worth a try to those of you experiencing pain.
End of lesson. You may press the button.
Somebody correct me if I'm wrong (I can certainly count on that around here...) but I thought it was pretty widely accepted that the Dvorak keyboard being faster or better is a myth.
Alright, a quick Google reveals that this is not commonly accepted. The defense is pretty shaky thought ("the Navy wouldn't do that.")
Anyways, repetitive movements are what cause the (quetionable) RSI condition, and I don't see how changing the keyboard layout would help, short of something more radical like one of those Logitech/MS 'natural' keyboards... and I don't believe Dvorak is inherently any faster than Qwerty; when comparing two people who know both very well, the typing speeds are probably the same.
You'd do much better to lower your keyboard to take the strain off your wrists. Most people keep their keyboards too high.
If Jesus wants me it knows where to find me.
RSI is basically tendinitis. There are a million causes for it and it is hard to track down. If you get it, you have to spend a good deal of time tracking down exactly where the cause is.
Both are awful to have. But you can't appreciate the pain until you get it. It is disabling...try to get through your day without hands. Driving, eating, washing...all the basic necessities hurt like hell.
Computer use is certainly a good aggravator, but you can get it from a variety of ways. It is very much a black science when you go to the doctor. Some people have the most awful ergonomics but suffer nothing, while people with perfect ergonomics get it.
This asdf jkl; thing really cramps my style, to put it punnily. Since I was a wee lad, I have been typing in my own style, without any major trouble. A few times along the line I have tried to type in the traditional way, and since I mentally know where the keys are by now, can adjust well enough to type that way at a modest rate. I find, though, that my hands become cramped very quickly then, especially on my Happy Hacking keyboard, but even on my large IBM Model M.
I have seen enough coworkers walking around with wrist braces bearing real enough grimaces to take the problem of wrist pain seriously, and don't think they were making it up. So I have experimented with "ergonomic" keyboards, including the Microsoft Natural. While it is comfortable to "touch type" on the Natural, it is even more comfortable to type my way. I believe it is because the way I type, my hands can always fall back to a relaxed position, elbows wherever they need to be, rather than the uncomfortable T-Rex arms I have when using the home row.
These researchers conceded that mousing might be at fault, and I have found that the best thing I have done for wrist and shoulder comfort was to get a Happy Hacking and a small trackball. The sole reason being that getting rid of the numeric keyboard put the mousing device a good deal closer to my hand.
I use a computer about 80 hours a week, which
:-)
is a lot I know. And a few months ago I got a pain in my left wrist, so I stopped and actualy took some sick leave.
But even after a week it still was painfull to type, so I tried to find out why and I located the problem to using the ctrl key, which made my hand strain (especialy the ctrl-b and ctrl-f combinations).
The solution was rather simple, I remamped my ctrl key to the caps-lock key (old keyboards actualy had the ctrl key there). And I disabled the old ctrl key so that I would unlearn to use it.
The next day and ever since I'm typing happely again. Except, I get confused when I have to type on some one elses workstation
BTW I already had the caps-lock disabled anyway, because I mostly use vi and it is rather anoying to see your lines joined instead of moving downwards, when you accidentaly have activated the caps-lock.
I've noticed that most people I've known who have these problems use low sensitivity settings for their mice, and often move their whole arm and wrist .
Everyone else I know, however, uses extremely high sensitivity and accelleration settings. (I tweaked the reg keys in Windows to get it as high as I wanted.) I grip the mouse lightly with my fingers, and only they move. My wrist, my arm: both remain stationary. The mouse itself moves no more than a half-inch in any direction no matter what I'm doing (and at 1600px no less).
I suppose the point I'm trying to make is that these problems are avoidable, and they're caused by poor practices more than anything else.
In the infinite wisdom of the Polish Doctor from the old joke, "Stop doing that!"
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if its not a significant risk, then why did I get nearly debilitating pain in my wrists when I coded all day long with a standard keyboard, but it went away as soon as I switched to an M$ natural keyboard? I'd never had such pain before, and since I've switched, I haven't had it return. I'd say that this pain was "caused" by the use of a lousy keyboard for long periods - but maybe I'm deluding myself.
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A long time ago in a land far, far away, I used to be a forest worker... you know, a lumberjack. I know people who *really* got carpel tunnel from swinging axes all day removing bush and I personally got carpel tunnel trimming trees (which involves hoisting a 30lb running chainsaw completely above my head) and brush. I *know* what real carpel tunnel feels like as your muscles and tendons rub the mylar insulation away from critical nevers that control your hand and arms. It feels like you just got hit with 600volts. There's a reason that chainsaw carrying forest wokers wear steel toed boots, heavy gloves, eye protection and kevlar chapps.... because it sucks when you bleed to death in the woods because carpel tunnel caused you to drop your chainsaw while it's running at full tilt with the throttle lock on.
Next time I hear about a programmer getting a worker's comp. settlement because of carpel tunnel, I think I'll stop by their house and strap them to a running 36" chainsaw for 8 hours. Unless carpel tunnel causes your to fall out of your fancy aeron chair in sudden, shocking pain, then you don't have carpel tunnel... what you have is a work ethic problem combined with an ineptitude for figuring out how to use voice recognition software.
I wonder if this is one of those cancer-in-rats things. Feed a rat some insane dosage of something and surprise surprise, that rat gets cancer. Then somebody finally does a study with normal exposure (e.g. typing MAYBE 10k-20k characters per diem) and finds that it doesn't hurt you.
But what about those of use who use keyboards a LOT -- and use cramped, uncomfortable keyboards like those on laptops and palmtops a LOT. I mean, I am typing pretty much nonstop for about 16 hours a day. I have huge hands (with a size 12 ring finger) -- and sometimes, they just hurt. The 500k+ impacts per day on this click tactile keyboard can't be doing me any good. Am I the cancer rat? Can I safely ignore this stupid warning label engraved in my otherwise stylish black dell keyboard? Or can I expect the ligaments in my index finger to just tear one day, like a linebacker's ACL? Can you come back from such an injury? CAN I DROP MY LLOYDS' POLICY?!?
Hey freaks: now you're ju
This article confirms what a few of my friends and I have been saying for a while. We all are very active computer users (>10h/day usually, using computers for at least 15 years), and we all only suffer from pain in the wrist when we allow our stress levels to rise to intolerable heights or when we're doing something we really dislike.
From what I've seen in other people everybody who had severe wrist/arm/shoulder complaints that they were relating to their computer work was either:
- Working under a lot of stress and/or time pressure for prolonged periods.
or:
- Not happy with their work or their work situation.
I think that computer use puts you in a certain heightened risk group for RSI/carpal tunnel but in my opinion you only "get" RSI or carpal tunnel when you are under a lot of stress or generally not in a very relaxed/happy mental state.
I find that when I voice this opinion in the real world, people tend to be very offended by it... so just for the record, this is not a troll.
It seems to me that a lot of people complaining about RSI are in crap shape to begin with. Obviously, if you rarely stretch your body and use it in an atheletic capacity, (or if you are an athelete, but you don't properly stretch) it will start catching up to you. In my experience, everyone should stretch as much as one full hour per day, and they should begin with an even more intense regimen to establish good baseline flexibility. It is *amazing* how many aches and pains are due to stiff muscles in your back and legs. For the record, I've never had any RSI, and I've been using computers for an average of 6+ hours a day for twenty years. When I see someone complaining about RSI (which most people in their mid-thirties eventually do in my office), I view them as equivalent to lard-ass, McDonald's eaters that complain about having back pain. Hello?! Do something about your *real* problem (being inflexible (or fat)) before you get some surgery on your hand.
I find that double clicks and having to go down to the lower left corner to start a program can be hard on your "mouse" wrist. I use the old "olvwm" and find it to be the most ergonomic for me. The worst one ever was Windows 3.1.
- Typing more than 10 hours per day without significant breaks every 1-2 hours.
- Typing very repetitive, and/or difficult sequences for hours at a time (think Ctrl-Meta-Backspace-LeftElbow-Delete... in some applications).
- pressure on wrists while typing (if you rest your wrists on the desk while typing, you need to break that habit!)
From my own personal experience, here's what you need to do if you start to get warning signs (e.g. tingling wrists, fingers / pain in the elbow / numbness)- Take a break. Really, it helps a lot. And if you have a foozeball, air hockey or ping pong table THAT IS NOT A BREAK (do it, just don't count it as a break). Breaks should last 10-15 minutes and you should try to relax your wrists and arms.
- Watch your posture. This really is key. There are many nerve-related problems that start with hunched shoulders especially. If you experience pain, try taking a break and rotating your shoulders forward and then back, slowly about 5 times each while hanging your arms at your side.
I really hope this helps. Good luck to all you over-achieving hackers who make OSS possible!I have this theory, totally unsupported by any study and supported only by my own personal experiences, that proper typing is one of the big causes of carpal tunnel / repetitive stress injuries.
Think about it- "proper" typing is based around the concept of minimizing your hand/wrist/arm motion. With a limited range of movement, you're doing the same little movements over and over again.
Myself, I'm a pretty fast typist, but I use sort of a modified hunt-and-peck method. I use about three fingers on each hand and I can basically hunt-and-peck AND touch type. Scary. But anyway, my hands are constantly roaming all over the keyboard like a pianist, almost... I actually feel like this really PREVENTS stress injuries, since I've got a wide range of motion going on.
This is in addition to other, proper ergonomic measures such as arm rests on the chair, wrist rest in fron of the keyboard, etc... of course.
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I work on a computer at least 10 hours a day almost every day and I've never had problems except one time I went on a two-week Vacation without a computer. Within a week my wrists started hurting. A couple days after returning home and using my computer I was fine.
THE FINDING was based on a survey of nearly 7,000 workers... Computer use âoedoes not pose a severe occupational hazard for developing (the) symptoms,â the authors concluded.
The article doesn't state what was on the survey but I have a suspicion that there is no distinction between a computer user and a person that is mainly a typists. I've been a programmer for many years and although I would be considered a heavy computer user, I would not be a heavy keyboard user. I type parts of the program, think, type some more, take a break, etc. I'm not like a key data entry person. That person would type non-stop for hours. I say that either the study is flawed and/or the article is too short on details.
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That damned little puck-mouse that came with the Mac G3s. I used one for almost 2 years, and because it didn't support my palm correctly, it screwed up my wrist. I know that shortly after they came out, you could buy a cover that gave wrist support, but my previous employer wouldn't buy one, so my wrist has problems.
Of course, now I use trackballs almost exclusively, so it doesn't matter as much. Optical trackballs are SO nice!
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6+ hours a day? I probably wouldn't have any problems if I only worked 6 hours a day. Why don't you try putting in 10 hours of mouse intensive CAD/schematic entry, and then I'll be more inclined to listen to you talk out your lazy ass.
Its not computer use specifically thats the problem, its improper posture and position. This has been known since shortly after the problem was recognized.
I've used computers since I got my commodore 64 a little more than 15 years ago. Never had a problem, until this year.
This year, I sliced open one of my fingers bad. The bandage I was wearing changed my typing position, and within the 12 or so days I had the bandages on, my wrists started hurting and my fingers tingled. The bandage and wrist pain is gone now, but my fingers still do tingle on occasion.
If I have been able to see further than others, it is because I bought a pair of binoculars.
My girlfriend is a registered massage therapist and often fixes me. I can tell you that as a user who is mousing/typing eight hours a day, my forearms (especially the mousing right arm) are not healthy. Instead of the supple, flexible muscle that is supposed to be there, when my gf works on it it's like just under the skin there are lumps of chewing gum with crunchy pieces in them.
Thanks to her help i'm getting better, however, and can offer this advice:
- find the working position that is optimal for muscle relaxation. I have two desks put together in an "L" shape with an armless chair, so i can rest my elbows up at the level of the keyboard. What kills your muscles is having them flexed (even gently) for a long period of time.
- stretch every 30-60 minutes. I do these three forearm stretches and find them very effective:
1. Hold your arm straight out. Bend your hand forward at the wrist, pulling it with your other hand until you feel a gentle stretch. Hold it for at least 30 seconds (it takes at least this long for muscle fibers to get the hint and release.
2. do the same thing bending your hand backwards.
3. this one is more complicated but is really the money stretch: hold your arm straight out in front of you, make a fist with your hand and hold it tight. Rotate your arm to that the thumb-side of your fist is facing outward. Now grab the fist with your other hand and pull it down and outwards, simultaneously bending the wrist and rotating the arm further. If done properly you should feel a nice stretch all through your forearm. Be gentle: it's more important to hold it longer than to push it harder.
If you're a Canadian living in Ontario or BC, you can go see a Registered Massage Therapist - they do wonders, and can give you advice on stretching and posture. Also Active Release Therapy (or ART,) which is provided by certain RMT's and Chiropractors, is pure gold for more serious problems. I don't know what regulatory bodies exist in the states, but i know that in Canada's unregulated provinces (everywhere but BC and Ontario) a lot of massage workers are either foofie-lala new age aromatherapy types or borderline sex industry workers, as opposed to genuine health care providers - so be careful.
In all matters of opinion, our adversaries are insane. -Oscar Wilde
Through some Alexander technique and structural integration work (i.e., rolfing), I'm finally better.
Whereas my regular doctor blamed computer usage and recommended I take off a few months from work, my PT believes this my symptoms were caused by poor posture over a lifetime - shoulders drooping forward, neck dropping forward. I believe the PT more than my doctor. (I have since changed doctors.)
From reading the posts it sounds like if you
use the right keyboard, the right pressure,
take breaks, have the right posture, etc then you'll be ok.
All those preconditions sounds like there's a
lot of risk to me. Rock climbing is safe if
you do X, Y, Z. But if you don't, you are
screwed.
Well, I'm not sure, but my 9 months of CTS might contradict this finding.
Let me just start off by saying that you wouldn't want to wish CTS on your worst enemy. It's not a pleasant experience.
That out of the way, I can say, without a doubt, that typing was the cause of my CTS.
I was hacking up an Ericsson PABX controller for many many hours for many many days. I wasn't taking breaks, I wasn't stretching, and I was using a mouse and a normal keyboard.
At first my hands went numb on a Friday. I thought it was strange, but my wrists were fine and feeling was restored after the weekend.
About 3 weeks later, I suddenly got this huge amount of pain in my right wrist. The next day my whole right hand was paralised, and I took 2 weeks off work.
I returned to work after having trained Dragon NaturallySpeaking to program C with Emacs. After about a week, my voice was gone, and my throat hurt like hell. So I gave up on that.
I got an MS Natural Keyboard. It helped. I got a trackball and used my left hand instead of my right hand. That helped.
I also discovered an amazing program called Workrave that forced me to take breaks. I highly recommend that people use this program. Prevention is a good thing.
So anyway, it's been 9 months. I've been to physiotherapists, chiropractors, hand therapists, hand surgeons, etc. None have really fixed the problem. But it's "managable" now.
Anyway, I'm probably looking at some form of surgery in the next few months as I seem to be stuck in a "rut", having good wrist days and bad wrist days.
The moral of my story: if you're typing a lot, and you're not taking breaks, then you're in for an aweful experience. Do some stretches and stuff as well. Seems to help. CTS isn't fun. Very depressing at times.
Oh yeah, I'm 20. I've been programming for maybe 6 years. So you don't necessarily have to be old to get a form of RSI.
Oh, another good resource is the Typing Injury FAQ.
"To minimize reaching and to promote comfortable shoulder and arm postures, consider the following:
Place your keyboard and mouse or trackball at the same height; these should be at about elbow level. Your upper arms should fall relaxed at your sides. When typing, center your keyboard in front of you with your mouse or trackball located close to it. Place frequently used items comfortably within arm's reach.
To promote proper wrist and finger postures, consider the following:
Keep your wrists straight while typing and while using a mouse or trackball. Avoid bending your wrists up, down, or to the sides. Use the keyboard legs if they help you maintain a comfortable and straight wrist position. Type with your hands and wrists floating above the keyboard, so that you can use your whole arm to reach for distant keys instead of stretching your fingers."
Microsoft doesn't care. But they have information, and it's in their interest to keep you at your computer as much as possible.
5% risk, huh? Wow, that sure is small! Oh wait, they don't cite the baseline incidence, so who knows if its all that small. 5% could be a 300% greater risk for all we know.
No signifiant relationship between more than 20 hours of use of a keyboard? Great news, for me: I work 60 hours a week with a keyboard! Oh wait, they neglected to analyze the subset of individuals like me. Talk about a low powered measure and analysis. Did they even look at the distribution? I bet there's a slight skew.
Well I'm glad the numbness in my palm isn't caused by my excessive computer use. Then what the hell is causing it? I sit on my butt all day and sleep on my back all night! What else could it be?
Seriously, until every scientist on Earth is forced to pass a course on psychometrics, this kind of research gets us nowhere. Statistics is a garbage in, garbage out practice.
You conclude that because your breaks give you time to recover, avoiding RSI should be a matter of common sense for everyone--not so fast pal. Sometimes conditions can change and what was once adequate rest is no longer adequate. When conditions change quickly you have no previous experience to draw upon, and you can do damage even while behaving prudently.
My RSI (a tendinitis, not carpal tunnel) hit me out of the blue when I was 26, and I've never been the same since. Perhaps an infection rendered my tendon sheaths fragile for a few days, or for some reason my collagen production decreased temporarily. But whatever the cause, I was past the point of no return in no time flat. The change was so abrupt that it may not have been possible to avoid at all.
It could have just been the awareness level, but Repetitive Stress Injuries seemed to have arisen with increased obesity in america, which seems to correspond with a lack of activity.
But then again, the typewriter has been around longer than the computer, and there used to be warehouses full of typists that did the jobs that computers automate these days. But RSI only seemed to rise in the computer age, which seems to correspond with the american obesity age.
Hey, I'm just your average shit and piss factory.
I used to be a pretty hard core Quake, QuakeII, QuakeIII, Blood, etc gamer. I'd play with my co-workers (always during non-working hours...;) until my hands throbbed. Then I went home and had dinner. Then I'd wait for maybe an hour or two and then BAM! hit the gamespy servers for another go at it until 2:00am or when my face hit the keyboard. Now the thought of doing that sends chills up my pained arms, shoulders and neck.