For many in the audio industry, working with sound and music is a conscious alternative to working in more "main-stream" occupations. But while the hours may be different and the work more creative, the reliance on computers that permeates the business world has been at work in the recording industry as well. The typical audio engineer and (particularly) sound editor is, like the typical office worker, far more likely to use a computer regularly now than ten years ago. And just as the benefits of computers apply in both realms, so do the risks. Repetitive Strain Injury (RSI), potentially leading to chronic pain and permanent impairment, is by now a well-documented phenomenon among workers in a variety of computer-intensive fields. It is not known how widespread the problem is among audio professionals, but it is clear that some risks may be even greater in audio workstation applications than in the general office.
Also known as Cumulative Trauma Disorder, RSI is basically a matter of bodily wear and tear. RSI is not a specific condition or "disease," but rather an umbrella term for a collection of conditions arising from the accumulated trauma of motions constantly repeated over long periods. "There is actually not a lot of good research out there to help us understand the underlying causes of RSIs," says Dr. Paul Handleman, who practices in the Occupational Medicine Clinic of the Kentfield Rehabilitation Hospital in Kentfield, Calif. "But I think our bodies are simply not designed for very limited-amplitude, repetitive muscular activities."
The consequences of RSIs can range from mild discomfort to serious disability. "This can be a serious and very painful condition that can occur even in young, physically fit individuals," says Paul Marxhausen, whose excellent Web page on dealing with RSIs is hosted by (though not an official publication of) the University of Nebraska at Lincoln: engr-www.unl.edu/ee/eeshop/rsi.html. "It is not uncommon for people to have to leave computer-dependent careers as a result, or even to be permanently disabled and unable to perform tasks such as driving or dressing themselves." Marxhausen describes the most common warning signs of RSI as: "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; and feeling a need to massage your hands, wrists and arms."
According to the online RSI/Ergo Information FAQ (www.tifaq.com./information.html), activities that may cause or aggravate RSIs usually involve one or more of five main risk factors:
* Repetition: performing repeated motions in the same way with the same body part.
* Posture: placing a joint toward its extreme end of movement in any direction away from its neutral, centered position.
* Force: performing an activity with excessive muscular exertion/force.
* Static Exertion: holding an object or a body position in a still, fixed manner.
* Contact Stress: direct pressure on nerves or tendons due to resting the body part against a hard and possibly angled surface.
RSIs crop up in all sorts of occupations, from assembly-line workers to musicians (providing a good excuse for those of us who have been negligent about practicing our scales). But in the age of computing-perhaps in part because of growing overall awareness of occupational health and safety issues-the problem seems to have reached epidemic proportions. "There are risks associated with any task in which you use the same set of muscles and tendons to make the same movement over and over again," says Paul Hendrix, rehabilitation technologist at the Center for Accessible Technology in Berkeley, Calif. "But the problem has become more significant with computer use, because it's possible to work at a computer uninterrupted for hours and hours at time."
For clerical and office workers, these hours and hours of uninterrupted work are often focused on the computer keyboard-lots of word processing and data entry. The typical user interface for an audio program, on the other hand, doesn't involve much typing; it tends to be very graphically oriented and thus mouse-intensive. But there is little consolation in the distinction. Constant use of a mouse or other "pointing device"-particularly dragging with the mouse button held down to select regions for editing or processing-can be even more hazardous than simple typing.
"Mouse use is especially problematic," says Hendrix. "A lot of people that I see with RSIs are people who are doing a lot of mouse-based work. One reason is that there is really only one way to hold a mouse, so you are using your hand and finger in the same exact position, which guarantees that your movements will be repetitive. It also requires gross movement of the arm and shoulder to move the mouse on the surface of the desk. And because there is not always a convenient flat spot in front of you, the mouse sometimes winds up being put up and far to the side, which results in positioning problems. Also, unlike typing, you are only using one hand to do it, which concentrates the load on just one part of your body."
Another factor that can increase the risk for audio professionals is that console-dominated mixing rooms are not often set up to provide an ergonomic setting for workstation use; the room's existing equipment and fixtures may preclude ideal placement of the keyboard, pointing device and/or monitor. And then there is the issue of reasonable work habits: Marathon editing sessions with few (if any) breaks can turn even the best-positioned setup into a source of trauma. "A lot of the people that we see in creative fields work really hard," Handleman says, "harder than most other jobs. When they are in production, they are going 10, 12, 14 hours a day, and they are totally into their work. So it's really challenging, because you can tell them not to overuse the computer, and they are going to do it anyway."
AN OUNCE OF PREVENTION"RSIs are far easier to prevent than to cure once contracted," says Marxhausen. Luckily, there is much that can be done in terms of both setup and work habits to reduce the possibility of developing problems.
Many of the work habits are simply common sense, based on the notion that you can avert repetitive strain by minimizing both repetition and strain. Use a light touch at the keyboard. Vary your routine, organizing your workday so that computing time is interspersed with other tasks, or at least intersperse different types of computing tasks rather than concentrating all activities of a given type into long, uninterrupted blocks.
Taking regular breaks is crucial. "The most significant thing you can do to avoid problems is to give your body breaks," Hendrix says. "Taking a break and shaking things out can help a lot. There is research that suggests that as little as a minute or two every 20 to 25 minutes can significantly reduce your risk."
Ideally, breaks are coupled with exercises that stretch the built-up tension out of hard-worked muscles and tendons. Marxhausen describes some exercises on his Web page (illustrated with animated GIFs), and also provides links to additional stretching information. The American Academy of Orthopedic Surgeons' site (www.aaos.org/wordhtml/aaosnews/exerci.htm) has diagrams of a simple stretch routine (see illustration) that was found in a study led by Dr. Houshang Seradge of the University of Oklahoma to "decrease the median nerve pressure responsible for carpal tunnel syndrome" when used regularly (start of each shift and after each break). Carpal tunnel may not be the most widespread form of RSI, but the study adds credence to the general notion that stretching can be an effective preventative measure.
Equally important to work habits is the setup of the working environment. Basic ergonomic setup is outlined in any number of sources, including the documentation that comes with many computers. To recap the fundamentals: Your chair should provide adequate back support and be adjusted so that your feet are flat on the floor with your thighs horizontal. The height of your keyboard and pointing device should be such that your forearms are level and wrists straight when poised over the keyboard in typing position. This means a standard 29- to 30-inch table or desktop is too high for the keyboard and mouse. The pointing device should be within easy reach without stretching. The monitor should be 18 to 28 inches away with the top of the viewing area at or just below eye level, and positioned to minimize glare from windows or artificial light sources. Ideally, everything you need to use frequently should be within easy reach.
Once you meet these basic ergonomic criteria, you can, if needed, add accessories to improve your positioning and comfort. A wrist pad to support the arms between (but preferably not during) keystrokes is a standard part of most setups. It's also important to keep your wrists and hands warm while working in air-conditioned rooms; various partially fingered gloves and wrist wraps are available for that purpose. Footrests, monitor arms and document stands are also common. More esoteric-and expensive-are pivoting forearm supports that mount to the front edge of the table. "Some people really benefit from pivoted forearm rests," Handleman says. "You can move the whole arm to take some stress off the wrist and hands, but you don't have to hold up your arm with the muscles in the shoulder and upper back." A detailed discussion of the ergonomic pros and cons of various accessories may be found at the F-One Ergonomics Web site (www.ur-net.com/office-ergo/pros&.htm).
ESCAPING THE MOUSE TRAPEven with a textbook-perfect ergonomic setup, heavy mouse use can still create problems. "I seem to see more problems from use of a mouse than from typing," Handleman says, "though it depends on how intensively the mouse is used and how much clicking and dragging is going on. When you type properly, you are using most or all of your fingers, but with a mouse you end up using basically your index finger, with the hand in a fixed position. So it can be a more difficult situation to deal with."
Adding to the problem, Handleman says, is the fact that most people are never shown how to use a mouse properly. "You're really not supposed to use the end of your finger to tap the mouse button," he says. "It's actually supposed to be the middle third of the finger that touches, because if you are curling your finger and tapping, you are contracting your muscle while pressing."
One of the simplest ways to avoid mouse-related strain is to learn to use keyboard equivalents. "Whatever software you are using, there are more than likely a lot of tasks that have keyboard equivalents," says Hendrix. "When you look at the interface of Logic Audio, for instance, you see a lot of sliders, but you can control almost all of the settings with keyboard commands that cause the sliders to move. So if you learn to use the keyboard commands, you may be able to avoid some problems."
Dave Froker, general manager of Digidesign in Palo Alto, Calif., agrees that "people who use a program all the time can learn the keyboard shortcuts and use them whenever possible." Froker adds that while he has never heard of anybody having problems as a result of working with the company's software, "we do recognize that not everyone likes to use the mouse for everything. That's why we developed our ProControl mixing surface, so that you have the choice of using hardware faders and buttons."
Short of a control surface, there are other less-specialized input devices available as alternatives to the mouse, including track balls, track pads and graphics tablets. None of these devices will eliminate the risks associated with repetitive overuse, but depending on the type of work and the shape of the individual's hands and body, they may reduce the potential for damage. "You can't give everyone the same thing," Handleman says, "because what works for one person doesn't work for another."
Because the choice is so individual, Hendrix recommends that people "go to a computer store and pull out a few devices, and see which one best fits their hands and the kind of work they are going to be doing. Take a look at your limbs while you are working, and ask yourself whether they seem to be in a relaxed, neutral posture, or contorted in some way. Ideally, you want a straight line from your elbow down through your little finger, and you want your wrist to be straight, or maybe bent downward a little bit."
Track balls are probably the most widely used of the mouse alternatives. "Track balls are generally better than mice," Hendrix says. "For one thing, because they don't need space to roll around, you can position them more conveniently so you don't have to reach as awkwardly. And you can find more different ways to move the ball, mixing your movements to avoid repetition. With some track balls, however, if you use them while resting your arm on the desk, your wrist is extended backward at almost 45 degrees, and eventually that will screw you up. Also, avoid the ones that restrict you to using them in only one way. The ones that are designed for moving the ball with your thumb are especially bad."
For those who are doing a lot of dragging-selecting regions in a sound file, for instance-Hendrix suggests getting a device that allows you to lock in a "mouse down" position. "For many people, the most painful thing to do is to drag stuff, because it requires them to move their wrist while holding one finger pressed down. Rotating your wrist while pressing down with your finger creates a likely point of injury." The Kensington line of track balls, for example, allows you to define a button combination that holds a mouse-down state until you next click.
"If clicking is more of a problem than just moving the ball around," Hendrix continues, "there are a number of mice and track balls available commercially that allow you to plug in an external switch, such as a foot-pedal. And if you are handy with a soldering iron, you can rig that up yourself by putting a jack in parallel with the button switch."
The favored solution among graphics professionals and others who need very precise control is the graphics tablet, which is used in combination with a handheld stylus. Tablets can also work well in non-graphics applications. "Many people who have developed RSIs from mouse and keyboard use," Hendrix says, "do not find it uncomfortable to write with a pen, in which case a digitizing tablet might be a good solution."
Another mouse alternative, one that lets you use your fingers to point directly, is to use track pads. But Hendrix cautions that tracked performance can vary depending on skin moisture. "Most track pads detect the disturbance of an electrical field, caused by the capacitance of your finger. That varies depending on the individual; if your skin is dry, the behavior of the tracker can be erratic. But many people don't have that problem."
If you have the resources and you are comfortable with several different ways of interfacing with your computer, you can further reduce repetitive motion by alternating between several input devices. "Change off pointing devices," Hendrix suggests. "Have a couple plugged into a serial switch box, and regularly switch from one to another so you are not using the same exact motions all the time." Some devices for the Macintosh's ADB bus feature plugs designed to allow several input devices to be daisy-chained together.
Voice recognition software is another option to consider to minimize strain on hands and arms, though there is a risk of straining your voice, as well. You probably won't be able to speak commands while mixing because the ambient noise level will be too high for the program to clearly recognize your words. But in editing, one often performs an operation in silence and then listens back when processing is complete. "If there is a keyboard equivalent," Hendrix says, "you can program that task to be associated with a voice command. But as a general rule, voice input programs do not do a good job with mouse movement, because they are sending discrete commands, and it tends to be very cumbersome to get the cursor to move exactly where you want. Dragon Systems has a nice approach called MouseGrid, which allows you to specify numbered points within successively smaller sectors of the screen, but even so, it requires a number of steps to get where you want to go." Reviews of leading voice recognition packages may be found on the CAT Web site, www.el.net/CAT/voicein/VI.html.
PROFESSIONAL CAREAs noted above, prevention is far easier than cure. But what if you are already experiencing one or more RSI-related symptoms? The most important thing to recognize is that RSIs don't just go away as long as the causative conditions and activities are still present. The sooner you begin to deal with them, the better. Particularly if you've already made the suggested changes in ergonomics and work habits and are still having symptoms, the consensus seems to be that you should consult a professional health care provider as soon as possible, hopefully one who is experienced with RSIs.
"We all have occasional aches and pains that go away in a day or two, especially when we overdo anything," says Marxhausen. "But if you have symptoms regularly when you are using the computer, run, do not walk, to your doctor or health care provider right away. Dealing with this early is critical to limiting the damage. By the time you have symptoms, there has already been some damage done, and if you try to ignore the pain, you may sustain a serious injury."
"There is a natural evolution in a lot of these things," Handleman agrees. "It can go from a hand problem to a problem of the entire upper extremities and eventually a neck and back problem, as well."
So what can you expect from your health care provider? "I first do a thorough evaluation to determine what's going on," Handleman says. "What level of damage do they have? What areas of the body are involved? Do they have nerve involvement? Then I recommend treatment, which might include hand therapy, physical therapy, which covers the rest of the body, acupuncture, deep tissue massage or osteopathic manipulation.
"If it's a hand problem," Handleman continues, "I will often send them to a hand therapist, who does both treatment and prevention. The treatment can involve things such as heat, ultrasound and steroids on the skin. If the problem is minor, the treatment is usually of fairly short duration. They will also be shown stretching exercises to do periodically on the job. And we also use ergonomic specialists who go on-site and make a complete recommendation on the ergonomics of the workstation, because there has to be a reason why the problem is occurring."
When ergonomics and treatment alone aren't enough, minimizing the activities that are causing the strain may be the only way to give the injury an opportunity to heal. "If someone has a significant problem," Handleman says, "I will probably intervene in their workplace, putting them on some kind of modified work for a while to get things quieted down. In a typical job, with mild overuse, you might put someone on a computer restriction, say only two to three hours in the morning and two to three hours in the afternoon, or prescribe a five-minute break every hour to stretch out and relax. And if their situation is really bad, I'll take them off the computer completely for a period of time."
Of course, the audio field probably isn't what Handleman has in mind when he refers to the "typical job," where lawsuit-fearing management can enforce a doctor's orders. Working in a frequently unsupervised environment, the audio professional alone will likely have to balance the urgency of today's workload against the potential for disability down the road. Those who make a reasonable effort to set up ergonomically and work smart will probably have few problems. Unfortunately, there may be those among the rest who end up discovering the hard way that the risks of RSI are real.