Keyboard Ergonomics

keyboard, ergonomicGood keyboard ergonomics practices keep you productive and pain-free at your computer.

Over the past 30 years, as personal computers have grown from novelty to ubiquity, we have all become typists and data-entry clerks. Back when typists used manual and electric typewriters, injuries from such work were relatively rare. Within a decade after the introduction of the desktop computer, repetitive strain injuries and other odd new aches and pains started to appear.

Modern Computer Keyboards

So what changed? Why do modern computer keyboards cause so many more injuries than typewriters did?

We Are All in the Typing Pool Now

Many more people are typing now. Typewriters and data-entry consoles used to be confined to secretaries’ desks, typing pools, and computing rooms. Now no one outside of the executive suite has a secretary, while at the same time our information-heavy jobs require much more writing, analysis, reporting, programming, and other typing-intensive tasks.

Typing Used to Be More Physical

Manual typewriters, and even electric typewriters, involved more body movements, using the whole arm and a variety of muscles, which spread the burden of the movement across more anatomical structures. Modern computer keyboards are designed to require as little movement as possible, so a few structures — the fingers, wrists, and forearms mostly — do all of the work. Modern low-profile keyboards on laptops and desktops also make you reach for the keyboard differently, contorting your forearms into uncomfortable positions. Increasingly compact keyboards bring your wrists closer and closer together, causing you to bend your wrists to line up your fingers with the keyboard (“ulnar deviation” in medical parlance), putting you at risk for carpal tunnel syndrome and other repetitive-strain injuries.

Keyboards Are Now Part of a System

Old-fashioned typewriters weren’t inextricably linked to a typing and computing system. The whole computer arrangement (peering into your monitor and reaching out for your mouse and keyboard) promotes the notorious forward-shoulder office posture, which can result in impingement of the nerves and blood vessels that go into the arm and hands. In fact, much of the pain, tingling, numbness, and lethargy that you feel in your arms and hands is actually due to constrictions way up in your chest, shoulders, and neck that ensue from this posture.

Awkward By Design

Modern typing is awkward by design. The familiar QWERTY keyboard layout (named for the first six keys in the upper-left of the keyboard) was actually designed to slow down typists. Early manual typewriters frequently jammed as typists got the hang of the layout and began typing faster than the machine could handle. Despite the typists’ speed, the jams actually slowed down production, so it made sense at the time to throttle back their flying fingers so that they wouldn’t send multiple typebars smashing to the paper at the same time. That relic of the manual-typewriter age now makes typing more awkward than it needs to be.

Applying Ergonomic Principles to Your Computer Keyboard

Here’s how to apply ergonomics principles to the keyboard on your desk.

Neutral Posture

neutral posture at keyboardYour keyboard set-up should let you work with your wrists in a relaxed, straight, neutral position. Look at your wrists as you type. Looking from the top, can you draw a straight line from the midline of your forearm to the first segment of your middle finger? If not, your hand has deviated from its neutral side-to-side range, causing stress at your wrist. Looking from the side, can you draw a straight line from the side of your forearm through middle of the Y formed by your relaxed thumb and index finger? If not, your wrist is in flexion or extension. Working from the neutral position between both the side-to-side and flexion and extension ranges is the key to preventing carpal tunnel syndrome and other repetitive strain injuries.

Keep your forearms, arms, and shoulders in a neutral position. Place your keyboard so that you can easily reach all the keys with your shoulder blades retracted (pulled back toward the midline), with your upper arms hanging easily straight down at your side, and with your forearms lined up parallel with the surface of your keyboard. If your keyboard is flat and on a flat surface, then your forearms should be roughly parallel to the floor. If your keyboard slopes upward away from you, then your elbows should be a bit below the front edge of the keyboard to keep your forearms parallel to the keypad. Similarly, if your keyboard slopes down and away from you, your elbows should be a bit above the front edge of your keyboard.

No Reaching

reaching for keyboardYou shouldn’t have to reach for your keyboard. Positioning your keyboard so that it draws your hands and arms even just a few inches forward pulls your upper arms and shoulders forward, starting a pattern that eventually leads to the classic “office slump.” Instead, position your keyboard so that you can comfortably reach the main row of keys while keeping your upper arms hanging vertically at your side, with your upper arms resting against your torso.

Neither should you have to reach side-to-side as you work at your keyboard. Many modern office keyboards include a numeric keypad, typically on the right side of the keyboard. If you center the whole keyboard in front of you, you’ll end up constantly reaching to the left. Instead, place your keyboard so that the key for the letter “B” lines up with your body’s midline.

Proper Height

keyboard trayYour keyboard should be positioned so that it is approximately level with your elbows when your arms are hanging naturally at your side. For most desks, the best way to hold your keyboard to achieve this height is to use a keyboard tray that hangs under the front edge of your desk surface. The tray should be wide enough to accommodate both your keyboard and mouse. If you have a numeric keypad on your keyboard, this means you’ll probably need a tray that’s at least 24 inches wide, and ideally a little wider. Many, if not most, keyboard trays are narrower than this. Keyboard tray designers seem to favor a narrow profile, so you may need to shop around for a tray that is wide enough. As of this writing Kensington was producing a 26-inch-wide model and ItalModern a chic-looking 30-inch-wide model. Regardless of the exact width of your tray, make sure that you can position your keyboard tray so that the letter “B” on the keyboard lines up with the middle of your torso, as discussed above.

Some keyboard trays are mounted on a height-adjustable swing arm. These arms also move forward and back as they adjust up and down. Make sure you account for this front-to-back movement as you position your keyboard tray in relation to your chair and monitor.

No Pressure Points & Minimize Static Load

If you have positioned your keyboard at the correct angle, height, and distance for your body, you are unlikely to experience undue pressure on your arms, wrists, or hands. If you do feel pressure, reevaluate your arrangement and see if you can make adjustments that reduce or eliminate it.

keyboard wrist restAfter you are satisfied with the angle at which your hands and forearms approach your keyboard, if you still feel like you have to work at it to keep your arms and hands comfortably positioned over your keyboard, you may want to use a wrist support. If you use a wrist rest, make sure that it is supportive enough to comfortably hold your wrists in line with your keyboard and soft enough to feel comfortable against your wrists. Your wrists should feel supported but not compressed. Many wrist rests are made of somewhat exotic materials, so if you have any allergies, be sure to carefully examine the list of materials before buying.

No Excessive Motion

When it comes to typing, the surest way to eliminate unnecessary motion is to learn to touch type. This skill not only distributes your typing effort across all of your digits, it also keeps you from having to constantly look down at the keyboard, helping you avoid neck strain as your head bobs up and down.

USB TypewriterOn the other hand, looking at the world through an office-fitness filter, always looking for ways to add gratuitous NEAT movement into your workday, you may ask if there’s a way to re-introduce old-fashioned, less-painful, manual typing to the modern office. Indeed there is. The USB Typewriter company helps you convert your old manual typewriter into a modern keyboard input device with a do-it-yourself kit, or you can buy a typewriter that they have already converted for you. I don’t know how NEAT this actually is, but I can guarantee that it would be a lot of fun.

Alternative Keyboard Styles

Lots of us still use standard-issue flat keyboards that come with our computers or on our laptops, but a number of ergonomically more friendly keyboards are available.

You have likely seen the fancy “ergonomic” keyboards made by Microsoft and other manufacturers. These keyboards split the key surface in half and raise it in the middle so that your keyboard looks a bit like a small tent. This keeps you from having to rotate your hands all the way down to a flat position, reducing pressure on your wrists and forearms.

Kinesis Advantage keyboardMany other alternative keyboard designs are available. Some slightly angle the keys themselves. Some split the keyboard while keeping the conventional straight layout to reduce your need to pronate (to turn your palm downward) your wrists. Some models, notably those from Kinesis, have little keyboard wells designed to minimize the need to reach for the keys. Some completely split the keyboard so that you can line up each half directly in front of each of your arms. There are even split keyboards that are completely vertical so that you interact with your keyboard more like an accordion player than a typist. A massage client of mine once cut a conventional keyboard in half and hung it over his chair like saddlebags so that he could type with his arms hanging straight down at his side.

All of these designs make sense, in that they attempt to reduce unnecessary pronation, ulnar deviation, and wrist flexion or extension. Many people report more comfort when they use these alternatives. No extensive research supports one option over another, so I urge you to experiment and explore to find the right alternative for you.

Dvorak keyboardOne other alternative is available: The Dvorak keyboard layout was designed to undo the deliberate obstacles of the QWERTY layout. A Dvorak keyboard places the most commonly used letters on the middle row of keys under your strongest fingers and is laid out so that common letter combinations alternate between hands. This lets you type using less finger motion, reduces errors, and can increase your typing speed. Most modern computers let you change your keyboard to the Dvorak layout. Because of the steep learning curve, however, few people actually use it. Still, if you are just getting started with typing or you have the patience to re-learn touch typing, the Dvorak layout is worth exploring.

Regular breaks

Operating a keyboard is one of the leading causes of repetitive strain injuries in the office, so it is particularly important to take regular breaks from typing and data entry. Try to alternate between typing and other tasks as much as possible, and take regular breaks to stand up and stretch out your wrists and forearms. Even better, you can eliminate typing almost entirely with Dragon Dictate and similar voice-recognition software.