Volume 19, Number 8
December 2002


Ergonomics:Friend or Faux?

By Alan Hedge

Nowadays, even lawyers often spend a large portion of in-office time at workstations and not formal desks. At such times, the physical relationship between a computer and its user can have a significant impact
on quality of life issues. Liabilities include evening eyestrain due to squinting at a glary screen all day, missing Saturday morning soccer cause you're laid up with a bad back, and almost missing an essential filing date because the asso-ciate assigned to the case sees his physical therapists Tuesday mornings.

If you've been experiencing increased fatigue, physical aches and pains unconnected to a clear source, frequent headaches, or sudden loss of strength in your hands from time to time, your body could be telling you that your workstation relationship is headed for the rocks (which, come to think of it, might actually be more comfortable). During the next few days, take the time to observe yourself and co-workers, and check out the following:
Who uses the computer? If the station has only one user, the layout can be optimized for that person's size and shape, and features such as an adjustable chair may be unnecessary. If it's going to be used by several people, you'll need to accommodate the extremes-the smallest and tallest, thinnest and broadest, as well as those in between. To do this you should supply an adjustable keyboard/mouse tray and an adjustable chair.

How long is the user at the computer? If it's only a few minutes a day, ergonomic issues may not be a high priority. But more than four hours of fairly steady use should warrant an ergonomic arrangement.
What kind of computer-desktop or laptop? Most ergonomic guidelines for computer workstations assume a desktop system in which the computer screen is separate from the keyboard. Laptop computers-rapidly growing in popularity for office use-are great for short periods of computer work or for people who attend and take notes at a lot of meetings. Guidelines for laptop use are more difficult because laptop design is inherently problematic: When the screen is at a comfortable height and distance, the keyboard isn't, and vice versa. If you use a laptop for sustained periods, consider adding an external monitor; an external keyboard, preferably with a negative-tilt keyboard tray; or both of these and a docking station.

How does the setup affect posture? Studies show that the best sitting position for computer use is at a relaxed recline of about 100 to 110 degrees-not the usual upright, 90-degree desk posture. As you often may have suspected, erect sitting is not relaxed and sustainable without strain; reclined sitting is-it significantly decreases muscle activity and intervertebral disc pressure in the lumbar spine. Other options to consider include sit-stand workstations and height-adjustable, split versions, depending on the type of work.
What kind of work does the user do? Try to anticipate what types of software will be used most often: word processing, where the best keyboard/mouse position is the highest priority; surfing the net or graphic design, where the best mouse position is most important; or data entry, where the best numeric keypad/keyboard position counts most. Does the user wear eyeglasses? Natural changes in vision due to aging commonly start to show up in most people during their early 40s. For these people annual eye exams are a necessary part of healthy computer use.
How's the clarity? Buy the highest quality monitors you can afford; this may be even more important for your administrative assistants than for yourself. Make sure that the text characters on the screen appear sharp. If you can see the screen flickering out of the corner of your eye, increase the "refresh" rate of your monitor. (On a PC use the monitor control panel in Settings/Advanced/Monitor; for Macs use the Monitor control panel.) Also consider investing in glass antiglare filters or quality LCD display screens.

What about the Gizmos?
Just about all new office equipment is labeled "ergonomically designed." Much of the time, the claim isn't true-and some of the products actually can make things worse. If you're thinking about using ergonomic products, ask yourself the following three questions:
1. Do the product design and manufacturer's claims make sense? Can the manufacturer provide research to support its claims? Be suspicious of products that haven't been studied by researchers.
2. Is the product comfortable to use for prolonged periods? Some ergonomic products may feel strange or slightly uncomfortable at first because they change your posture, but this is usually beneficial in the long term. If a product continues to feel uncomfortable after a reasonable trial period of about a week, stop using it.
3. What do ergonomics experts say about the product? If they don't recommend it, don't use it.

Rating the Products
Research has shown than certain categories of "ergonomic" products are more helpful than others, and even the best equipment must be carefully installed and properly used.
Keyboards. Many keyboards featured as "ergonomic" split the alphanumeric keys at an angle. For non-touch typists this design can be a disaster! The split design addresses only issues of hand ulnar deviation, and research studies show that vertical hand posture (wrist extension) is more important. No consistent evidence exists that most split-keyboard designs really produce substantial postural benefits. Using them will not cause problems for those who prefer them, and it may help. For most people a regular keyboard design works just fine if it's in the proper neutral position.
Mouses. Many alternative mouse/input designs work well to improve hand/wrist posture. However, check that you can use these with your upper arm relaxed and as close to your body as possible; overreaching to an "ergonomic" mouse negates its benefit. Consider multitouch keyboards that use a large touch surface or a keyboard with a built-in trackball to eliminate mouse concerns.
Wrist rests. These were very popular a few years ago, but research hasn't demonstrated substantial gains from their use. In fact, a wrist rest can actually increase pressure inside the carpal tunnel by compressing the undersurface of the wrist (take a look at your wrist while it's in typing position-you'll probably see blood vessels that shouldn't be compressed). Avoid soft, squishy wrist rests that contour to your wrist; they restrict free hand movement and encourage more lateral deviation during typing. Place the palms of your hands on a broad, firm support when you rest them.
Support braces/gloves. No consistent research proves that wearing wrist supports during computer use actually helps reduce the risk of injury. If you like wearing a support, make sure it keeps your hand flat and straight, not bent upward. Some evidence supports the theory that wearing wrist supports while you sleep can help relieve symptoms of carpal tunnel syndrome.
Armed with this knowledge, you should be able to eliminate many basic stressors before they announce themselves through painful musculoskeletal disorders.

-Task chairs should be armless, or the arms should be removed, especially for typing. Placing forearms on the armrests leads to rounding the shoulders. Typing with armrests seems to encourage lifting the elbows, which increases stress on the neck, shoulders, back, arms, and hands.

-Here's a simple test: Sitting in your current chair, place your arms on the armrests and reach out to your keyboard. Look at the position of your elbows and check for shoulder and neck tension. Then repeat the exercise, this time starting with your elbows in front of your rib cage. When you reach for the keyboard, you should notice a difference in elbow position, as well as less tension in the shoulders and neck.

-The best chair height allows feet to be flat on the floor, with the thighs parallel or close to parallel with the floor and lower legs near a 90-degree angle with the thighs.

- Turning your palms upward while sitting down and standing up allows you to use your legs more efficiently and helps stabilize your back. Turning palms up while standing from a seated position removes much of the pressure on your back during this action.

-After you buy a chair, place a sticker under the seat noting purchase date, warranty length, and seller (or tape a copy of the receipt and warranty to the seat bottom). Most chairs have warranties of several years. Having this information handy can save an individual hundreds of dollars and a large law office, thousands of dollars.

Desks have not changed in most office environments, especially the law office, where confidential interactions with clients make cubicle arrangements inappropriate. Desks still used in many offices were manufactured BC-before computers-but that hasn't stopped people from plunking CPUs and monitors right on top of them. A number of companies still use huge Steelcase desks dating from the '60s that have a top surface 30 inches from the floor and, in today's workplace, mostly make great earthquake shelters.

Most office furniture is built according to anatomical norms, which means it is designed for someone approximately 5 feet, 9 inches tall. On the West Coast, in fact, large numbers of office staff are composed of women from Pacific Rim and Latin American countries who average 5 feet, 4 inches or shorter. Even without such obvious regional differences, torso and leg length can vary to incredible degrees.

When seated at a desk, you should be able to lower your elbows only slightly before they reach the surface. If you cannot sufficiently lower your desk, you might be able to elevate your chair for a more correct balance. If you elevate the chair height, however, be sure to use a footrest. The Yellow Pages work as well as, if not better than, most footrests on the market and have the advantage of being adjustable simply by adding or subtracting pages. (Wrapping them with duct tape helps hold them together and keeps them from sliding around on the floor.) If you're buying furniture for use with computers, consider a bilevel workstation that allows the user to adjust the height of both the keyboard and the monitor.

Keyboard and Mouse
Because many people add computers to already existing office configurations, the physical act of typing can create numerous stresses and strains on the body. Ideally, the keyboard should sit one to two inches below the elbows, which allows the user to maintain a neutral wrist and hand position while typing. One of the worst things you can do is to type for extended periods of time with your hands in a hyperextended position (at an angle above the keyboard), because you have to torque your hand and wrist to strike a key. The neutral position allows you to strike a key using primarily finger movement. In addition, the monitor and keyboard should align with the vertical midline of your body. The middle of the keyboard is at the H key.

Mice and keyboards take up a lot of additional space on a desktop, so many people add keyboard trays to move the items to a different surface. Even today, trays are sold that do not provide room for the mouse, and the mouse usually ends up perched on the desktop-several inches higher than the keyboard and several inches beyond it. This position forces the user to move the arm, shoulder, and back to articulate the mouse. The mouse should be on the same surface as the keyboard and positioned so the hand can move in an arc from the keyboard to the mouse.

The computer monitor should sit directly in front of you, not off to the side so you have to twist to look at it. Even a few minutes of this aggravates joints and muscles in the neck, back, arms, and hands. The top edge of the monitor screen should be even with your eyebrows-unless you wear bifocals, in which case you may want the screen a little lower.

Try not to place the monitor directly under overhead lighting. This creates glare on the screen that leads to eyestrain and neck and shoulder tension. If you cannot avoid overhead lighting, a monitor hood can help cut down glare. For an inexpensive do-it-yourself hood, use folders or cardboard to create a shade around the monitor, which will dramatically improve your view.

Because the practice of law requires extensive reading and paperwork, place your reading material and papers on a slant. Law offices tend to be among the largest purchasers of three-ring binders, and I find that placing papers on the cover of an empty three-inch binder provides a nice slant from which to read and write.
A number of other things can be done to help reduce the possibility of cumulative trauma, such as taking frequent breaks and periodic stretching sessions throughout the day. Implementing some of the ergonomic changes suggested in this article can help ensure that small discomforts don't mature into medical conditions. As with legal problems, the advice of a professional injury prevention specialist often can help.

Breaking Is Hard to Do

All ergonomists agree that it's a good idea to take frequent, brief rest breaks. A rest break doesn't mean you have to stop working, just that you have to rest certain muscles.
Not all rest breaks are created equal. Throughout the day, different body parts may require different relief.
-Eye breaks. Staring at a computer screen causes changes in how the eyes work, slowing the rate of blinking and exposing more of the eye surface to air drying. Looking away from the screen every 15 minutes for a minute or two, preferably at a point more that 20 feet away, lets the muscles inside the eye relax. Before returning to your work, blink your eyes rapidly for a few seconds to refresh the tear film and clear dust from the eye surface.
-Microbreaks. Most typing is done in bursts rather than continuously. You may not even be aware how often you stop to answer the phone, respond to a question, recheck a note. As much as possible, rest your hands in a neutral, flat position when away from the keyboard. Microbreaks as short as two minutes allow you to stretch, stand up, move around, or do a different task. A microbreak isn't necessarily a break from work; it's a break for a particular set of muscles that's been doing most of the work (e.g., the finger flexors if you've done a lot of typing).
-Rest breaks. Take a brief rest break every 30 to 60 minutes. Think of these as moving breaks-get a drink of water, look outside, water your plant. Resting and exercising different muscles helps you feel less tired.
-Exercise breaks. Many gentle stretching exercises help relieve muscle fatigue. Rotate groups of them throughout the day, every hour or two.
-Big-Brother breaks. Working at a computer can be hypnotic, and it's easy to go long periods without realizing how long you've been typing and mousi g. Fortunately, software is available that can be programmed to remind users when it's time for a break. The best software runs in the background and monitors workflow, prompting you to rest at appropriate intervals and suggesting simple exercises. For the hardheaded, a special setting will fade the screen to black and send you to mandatory Timeout.
Free trials and downloads of such software are available (for individual users) from www.magnitude.com and www.cheqsoft.com/break.html.

Environmental Protection

Law office environments vary considerably, from streamlined, colorful models of hip to subdued and subtle enclaves of tradition. The following environmental factors can have major, sometimes daily impact on work quality and efficiency.
Lighting. A monitor that faces a bright window will look washed out, and one that backs up to a bright window will be hard to read. Consider moving the screen, preferably to a 90-degree angle; using an antiglare screen filter; or adding blinds or drapes to control the brightness.
Ventilation. Modern office buildings sometimes make a breath of fresh air impossible, but it's better than a cup of Starbucks to combat user fatigue. An adjustable heating or cooling system is also best but, again, often unavailable. Try redirecting airflow to accommodate personal differences or using a desktop air cleaner.
Noise. Noise causes stress and stress causes muscle tension, which can increase the risk of injury. Try to choose a quiet place for workstations. Pleasant background noise can help mask the hum of traffic, ventilators, or other sound sources.

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