Are Computers Hazardous to your Health?
Nov 21, 2001 11:45 AM
Recognizing and Preventing Computer-Related Health Problems
Repetitive Strain Injuries
Q: Please tell me about computer-related health problems.
A: Repetitive strain injuries (RSIs) to the upper body have occurred in epidemic proportions among computer users. These RSIs involve damage to muscles, tendons and nerves. They can cause pain, weakness, numbness or impairment of motor control. The parts of the body most frequently affected are the hands, wrists, fingers, arms, shoulders and neck.
The Congressional Office of Technology Assessment has ranked computer-related repetitive strain injury as the single biggest cause of occupational illness today.
Q: I’ve heard the term "cumulative trauma disorder (CTD)." Is that the same thing as "repetitive strain injury?"
A: Yes. Both names emphasize the fact that these injuries develop gradually, unlike a muscle strain or sprain that follows a single incident. Other names for RSI include "repetitive motion disorder (RMD)" and "occupational overuse syndrome."
Q: I keep hearing about computer operators who have "carpal tunnel syndrome." What is that?
A: It is a type of repetitive strain injury. Carpal tunnel syndrome occurs when the tendons in the wrist become inflamed and put pressure on the median nerve, which runs through a passageway made of bone and ligament that is called the carpal tunnel (from the Greek karpos, or wrist). The median nerve controls the muscles in the area as well as the nine tendons that allow your fingers to flex. Carpal tunnel syndrome causes numbness or tingling in the hand and fingers, particularly at night. The pain and potential loss of muscle control can be incapacitating.
Q: Are there other types of RSI injuries?
A: Although carpal tunnel syndrome gets the most publicity, there are many other forms of RSI. These include various forms of tendinitis (which can affect the fingers, wrist, shoulders, elbows and forearms), DeQuervain’s disease (irritation of the tendons on the side of the wrist and base of the thumb), cervical radiculopathy (compression in the cervical discs in the neck), and disorders of the radial, medial or ulnar nerves. Unfortunately, many doctors have not been trained to identify the wide range of repetitive strain injuries.
Carpal tunnel syndrome. These two views show the left palm. The median nerve lies on top of the wrist bones (left}, which are covered by a band of tendon and muscle that creates the "tunnel" that encloses the nerve (right). If the soft tissue of the wrist becomes inflamed, it puts pressure on the nerve, causing pain and possibly damaging it.
Q: What are the symptoms of repetitive strain injury?
A: Symptoms may include tingling, aching, swelling, stiffness, weakness and loss of sensation or motor control. Many people first experience RSI symptoms away from the job and don’t realize that they are work-related. Sometimes the symptoms are not experienced in the body part where the stress actually is occurring, making it difficult to identify the cause of the injury. For example, a computer user may experience hand pain, but the source of the problem may be repeated stress to the shoulder.
Q: Can lower back and leg pain also be associated with computer use?
A: Yes. Sitting in a chair with inadequate back support, or failing to use the back support provided, can strain the lower back.
A chair that is too high or too low or presses into the back of your thighs can cause pain in your legs and feet. Leg discomfort also appears to be related to sitting for long periods of time without movement.
Q: How serious is repetitive strain injury?
A: RSIs are difficult to treat and may result in perma nent disabilities. Some people injured by computer work find that they can no longer handle their jobs or the tasks of daily living — such as opening jars, folding laundry or lifting small children — without intense pain.
If an RSI problem is caught early and treated appropriately, recovery usually is possible. But permanent damage sometimes can occur within a few weeks after symptoms appear. If you have RSI symptoms, it’s important to take action as quickly as possible.
Q: What should I do if I have symptoms of RSI?
A: Seek medical attention from a physician familiar with repetitive strain injuries and take steps to change your working conditions. This booklet provides information about how to do both of these things.
Q: What is it about computer work that causes repetitive strain injuries?
A: RSIs are associated with the following risk factors:
- Repetitive motion (rapid, continuous keying).
- Awkward or fixed postures (bending wrists while typing or sitting in uncomfortable positions, at inappropriate furniture, for long periods of time).
- Use of force (heavy typing pressure or tight gripping of the mouse or trackball).
- Insufficient rest breaks.
- Working in a room that is excessively cold.
Q: Why didn’t secretaries develop repetitive strain injuries in the days before computers?
A: Some office workers did experience writer’s cramp and other RSI-type problems in the pre-computer era, but the number of people affected has increased dramatically. The lighter touch required on a computer keyboard, as compared with a traditional typewriter, makes it possible to type faster, and thus increases the repetitive motion of the fingers. With a typewriter, office workers had natural work breaks when they paused to hit the carriage return, change the paper or make corrections, but computer operators often type without interruption. And typewriters, particularly manual typewriters, had much larger springs beneath the keys to cushion the impact of fingers. Also, gripping the mouse or trackball stresses muscles in unaccustomed ways.
