Computer Related Repetitive Strain Injury
As more and more work, education and recreation involves computers, everyone needs to be aware of the hazard of Repetitive Strain Injury to the hands and arms resulting from the use of computer keyboards and mice. This can be a serious and very painful condition that is far easier to prevent than to cure once contracted, and can occur even in young physically fit individuals. It is not uncommon for people to have to leave computer-dependent careers as a result, or even to be disabled and unable to perform tasks such as driving or dressing themselves.
What is RSI?
Repetitive Strain Injuries occur from repeated physical movements doing damage to tendons, nerves, muscles, and other soft body tissues. Occupations ranging from meatpackers to musicians have characteristic RSIs that can result from the typical tasks they perform. The rise of computer use and flat, light-touch keyboards that permit high speed typing have resulted in an epidemic of injuries of the hands, arms, and shoulders. Use of pointing devices like mice and trackballs are as much a cause, if not more so. The thousands of repeated keystrokes and long periods of clutching and dragging with mice slowly accumulates damage to the body : another name for the condition is Cumulative Trauma Disorder. This can happen even more quickly as a result of typing technique and body positions that place unnecessary stress on the tendons and nerves in the hand, wrist, arms, and even the shoulders and neck. Lack of adequate rest and breaks and using excessive force almost guarantee trouble.
What are the Symptoms?
- Tightness, discomfort, stiffness, soreness or burning in the hands, wrists, fingers, forearms, or elbows
- Tingling, coldness, or numbness in the hands
- Clumsiness or loss of strength and coordination in the hands
- Pain that wakes you up at night
- Feeling a need to massage your hands, wrists, and arms
- Pain in the upper back, shoulders, or neck associated with using the computer.
How Do I Prevent It?
1. Correct typing technique and posture, the right equipment setup, and good work habits are much more important for prevention than ergonomic gadgets like split keyboards or palm rests.
The figure above shows proper posture at the computer. (Some current thinking suggests that a monitor position lower and farther away may be better. In addition, there are other opinions about what is the "correct" position. ) Note that the chair and keyboard are set so that the thighs and forearms are level (or sloping slightly down away from the body), and that the wrists are straight and level - not bent far down or way back. If the table is too high to permit this, you may do better to put the keyboard in your lap. Also note that the typist is sitting straight, not slouching, and does not have to stretch forward to reach the keys or read the screen. Anything that creates awkward reaches or angles in the body will create problems. Please note that even a "perfect" posture may result in problems if it is held rigidly for long periods of time: relax, MOVE and shift positions frequently. This isn't just about your hands and arms, either: the use or misuse of your shoulders, back and neck may be even more important than what's happening down at your wrists.
While you are actually typing your wrists should not rest on anything, and should not be bent up, down, or to the side.
Your arms should move your hands around instead of resting your wrists and stretching to hit keys with the fingers. (palm rests give you a place to rest your hands only when pausing from typing, NOT whileyou are typing.) When you stop typing for a while, rest your hands in your lap and/or on their sides instead of leaving them on the keyboard.
4. Wrists also should not be bent to the side
The following figure shows the wrong way
The following figure shows the correct way
5. Research suggests that all of the above is easier to do if you tilt the back edge of your keyboard down, away from you. Put a prop an inch or two thick under the edge of the keyboard closest to you, but make sure the whole thing is still low enough so you aren't reaching up. This is a good argument for getting an adjustable keyboard tray that permits optimal positioning.
6. INCREASE YOUR FONT SIZES.
7. DON'T POUND on the keys: use a light touch
8. Use two hands to perform double-key operations like Ctrl-C or Alt-F, instead of twisting one hand to do it.
9. TAKE LOTS OF BREAKS TO STRETCH and RELAX.
10. Hold the mouse lightly, don't grip it hard or squeeze it.
11. Keep your arms & hands warm.
12. Eliminate unnecessary computer usage.
13. Consider voice recognition.
14. DON'T TUCK THE TELEPHONE BETWEEN YOUR SHOULDER AND EAR so that you can type and talk on the phone at the same time.
15. TAKE CARE OF YOUR EYES. Eyestrain is also a related, widespread problem that should be addressed at the same time you are setting up your computer for healthier use.
16. PAY ATTENTION TO YOUR BODY. If typing causes you pain, stop. If the pain persists, consult a medical professional.
17. Evaluate other activities. Problems may be caused or aggravated by other things you do frequently. Sports, carrying children, hobbies requiring intense small work (like knitting), and excess effort/tension in other daily things may have enormous impact too.
Source : THE UNIVERSITY OF NEBRASKA-LINCOLN rsi.unl.edu, Wikipedia en.wikipedia.org/wiki/Repetitive_strain_injury