The more you type, the greater the chance you could develop aches and pains
Allow the keyboard to lie flat, below elbow height. For forearm support, push the keyboard back from the desk's edge so you can rest your arms on the table. The elbows can be bent at greater than 90 degrees.
If needed, use a soft-foam wrist rest (no thicker than the keyboard) to help keep the wrists straight during typing and minimize the upward bending of the wrist that can lead to injury. An alternative way to get forearm support is to use chair armrests.
It is OK to lean back a little in your chair.
Position the computer monitor directly in front of you. The top of the monitor should be no taller than eye height.
D r. Fredric E. Gerr, an occupational medicine physician at the University of Iowa College of Public Health in Iowa City, has been studying work-related musculoskeletal injuries since the mid-1990s. Here are five things he thinks people should know about aches and pains caused by computer use.
The more you type, the greater the odds of developing pain. In a 2006 review paper, Gerr and colleagues analysed 39 studies examining the link between computer use and musculoskeletal disorders in the hands, arms, shoulders or neck in 45,000 people. The scientists estimated that the risk of injury starts rising when a person uses a keyboard more than about 20 hours a week.
Carpal tunnel syndrome is relatively uncommon, occurring in about 1 per cent of workers within a year of using a computer on the job. “People assume that anything in the hand that tingles is carpal tunnel syndrome, but that's not true,” Gerr said. Although persistent tingling in the thumb, index and middle fingers almost always occurs in carpal tunnel syndrome, other conditions, like a pinched nerve in the neck, can cause the same symptoms.
The most common upper-extremity musculoskeletal ailments from computer work are neck and shoulder pains, which develop in about 60 per cent of office workers in their first year of a job requiring 15 or more hours of weekly computer use. About 40 per cent experience hand and arm symptoms, mostly from different kinds of tendinitis involving inflammation or degenerative changes in tendons.
Recommendations for safe computer ergonomics have been evolving. A decade ago, many experts advocated “neutral posture”: wrists poised flat over keyboard, forearms parallel to the floor, elbows at 90 degrees and the back positioned upright in the chair. But based on recent studies, certain adjustments to these guidelines are better. In particular, providing support to the forearms appears to lessen shoulder and neck pain, Gerr said, “presumably because you're not holding the weight of the arms up with the muscles of your shoulders while you're typing.”
NYT News Service