Predisposing Factors

(Chapter 7, excerpted from the book, "(Amazon) It's Not Carpal Tunnel Syndrome: RSI Theory & Therapy for Computer Professionals")

The following questionnaire spells out our criteria, or warning signs, for susceptibility to chronic RSI. The results won’t in any way determine if you have RSI—that’s a matter of diagnosis, determined by some direct observations and tests. It can, however, help you judge whether you should regard a single RSI symptom as a danger sign of more serious possibilities down the road, or accept it as a minor injury that might go away with a little rest and prevention.

If you don’t currently have any aches and pains, and you’re reading simply for understanding and prevention, the results of the questionnaire might give you a good look into your future. If you answer Definitely to many of the questions, you might be encouraged to get more serious about prevention.

We’ve made no attempt to disguise where we stand; notice that some questions have "yes" first; others have "no" first.

Susceptibility Questionairre

If you’ve indicated several answers in the "Definitely" column, we’d like to talk to you in our examining room. Step inside, please.

Understanding the Predisposing Factors

The Susceptibility Questionnaire is simply our estimation of common denominators among RSI patients with serious conditions. None of the criteria are intended to be strict or absolute—many folks type for years with no problem, and others make every ergonomic mistake in the book with no penalty. That’s life in the big city. But if you’ve noticed problems, especially numbness, pins-and-needles, or tingling, then your answers to the survey can help you determine how serious you should get about treating your condition. If you answered yes to a fair number of the questions, you’d be wise to regard your situation as a serious, potentially chronic RSI case, rather than an isolated ache or pain. Even if it is an isolated ache or pain, you can’t go wrong by being careful. Employ as many or as few of our recommendations as you think are warranted based on how it all adds up, and adjust accordingly as time passes by. Now let’s examine some of the individual criteria in the questionnaire.

How Do You Spell Workaholic? Does the following quote sound like it could be you:

The single, over-riding factor that makes you most likely to get RSI is being a maniacal worker. Contrary to what might be in the minds of some who wonder if RSI sufferers are malingering malcontents who want to take a free ride on "the system," our experience is quite the opposite. Make a list of the top producers at your organization. The RSI victims will probably have a disproportionately high representation among them. These people are serious, detail-oriented perfectionists. They love their work, hate to walk away from an unsolved problem, look for the most efficient way to work (so they can get more work done), and think about work all the time. You get the idea. These folks probably invite pressure and the stress that comes with it because they get the big jobs. It’s a fairly well acknowledged rule for managers, that you should give the most important jobs to the busiest people&ldots; they’re the busiest because they take on the most work. And the cycle builds on itself.

We asked our case study patients, "Do you believe your work style contributed to your condition? Here are typical responses:

If you could change your behavior to reduce only one of your predisposing factors, you should probably choose this one, your work obsession. This means somehow reducing the tension level with which you attack your work. Much more on that later.

How Long Have You Been Typing? I used to wonder if age was a factor in computer-related RSI, but now that computers are introduced in grade school, it’s not age—it’s "typing-years" that matter&ldots; perhaps combined with age. More young people are indeed showing up at the therapist’s doorstep. Combine a fierce work style with years behind the keyboard and you have the core ingredients for RSI. This highlights the possibility that the name cumulative trauma disorder may indeed be more accurate. It is the accumulation of tension on the musculoskeletal system that sets the stage.

Our case study patients had been typing for 6, 9, 10, 11, 13, and 14 years when they started developing RSI symptoms.

The Aging Factor The questions about how slowly you heal, and whether you ache after being in one position for a while refer to the general effects of aging. The critical body tissue involved in aging and its relationship to RSI is connective tissue, the material that comprises your tendons, ligaments, and fascia. Fascia is the sinewy material that covers muscles, nerves, and just about everything in the body, for that matter. By some accounts, the body slowly dehydrates as it ages&ldots; and the effect of this is most pronounced on connective tissue. If you notice that you’re not as flexible or resilient as you once were, it’s more likely that you will pay a price for habitual overexertion. We’ll discuss more about connective tissue in our discussion of anatomy.

Sedentary Lifestyle This one’s an interesting call. I have a relatively serious RSI case, but I’m far from sedentary and the anecdotal literature seems to tell of many active people who have RSI. Maybe if I were less active, I would have developed RSI after 5 years instead of 13. Perhaps our amount of exercise and other physical activity is not enough to counteract the 8-hour daily dose of static computer posture. Certainly, I exercise much less than I type. In any case, the less activity you give your arms, the more of an advantage you give the destructive forces of RSI.

Getting Enough Sleep? Every theorist seems to put sleep (the ultimate sedentary activity?), on the helpful side of the scale. Who are we to disagree? Sleep is restorative. For the first two years of my RSI symptoms, a good night’s sleep would alleviate them, seductively resetting my personal doomsday clock so I could go out and tear up my arms again another day. The most important part about sleep is simply that it’s eight hours during which you’re not typing. But beyond that, your tissues can recuperate and regain some of their normal flexibility and stamina. As far as the early onset of RSI for an individual, stamina is the key. If you get enough sleep, your shoulder muscles have the stamina to keep your upper torso from collapsing into the nerve network that innervates the arms. The "suspension bridge" therefore maintains the configuration in which it was designed to operate. In addition, the small muscle bands that activate the fingers have the stamina to work without inflammation.

There’s also some evidence that only an intense level of sleep is restorative. In other words, you must fall deeply asleep before sleep yields substantial, recuperative benefits. If your sleep is lacking, the stage is set for RSI. If the shortage of sleep is chronic—as it might be if you are under psychological stress, or if you have young children who often need attention at night—the risk is higher. These are factors that some believe contribute to a higher incidence of RSI in women.

Workstation Ergonomics In our context, ergonomics means working in the healthiest position, which means the most unstressed or "neutral" position. Your neck should be comfortably supporting your head, your spine should be in a natural S-curve, your arms touching the keyboard and mouse without reaching out, wrists unbent, and fingers relaxed.

Ergonomics is in the common-sense-but-unsubstantiated category of RSI explanations. It’s conceivable that you might work at the most uncomfortable workstation imaginable, and survive unscathed until your other predisposing factors put you in the danger zone. But the voluminous experience of individuals once they have RSI bears out the difference between good ergonomics and bad. I can reproduce a little scenario, on demand, that demonstrates bad ergonomics: I face my phone, put the phone handset between my ear and shoulder, twist only my upper torso from my phone to my keyboard (45 degrees), and type. In a few moments all five fingers of one hand start to get pins-and-needles. Many sufferers can distinguish the difference between straight wrists and bent, some within moments. It only makes sense to assume that these stressful positions are accumulating trauma in the pre-symptomatic typist. We’ll describe ergonomics extensively, in our section on therapy.

Other Factors: Disease, Medical History, Anatomy The factors we’ve listed above are the ones we consider to be the classics for inducing the typical computer-related syndrome. But there are other causes of the various RSI symptoms, and we don’t want to entirely discount these. Only an in-depth medical evaluation can determine if your problems stem from causes such as these: genetics, hormone problems, diabetes, broken bones, and anatomical irregularities (for instance, an extra rib pinching the thoracic outlet).

In some cases, the shape or relative sizes of your bones could predispose you to injury by repetitive motion. Conceivably, your carpal tunnel could be small—one study draws a correlation between the shape of one’s carpal tunnel and higher incidence of injury.

Other factors implicated in RSI are as diverse as hypothyroidism, use of oral contraceptives, arthritis, and improperly set bones. The same comment applies: if you don’t match up strongly against our classic criteria, all the more reason to rule out these factors with an expert in them, a physician.