Healing keyboards: ergonomically correct keyboards can help prevent wrist injuries.

After youve sitting at your computer keyboard typing all day, you may begin to feel some discomfort in your wrists, hands or arms. "Hmmm," you say, "Iv'e typed for two or three hours straight and never felt any discomfort before."

The typing that you thought was being productive could put you in a doctor's office, or worse, an operating room. The discomfort you feel is known as Carpel Tunnel Syndrome, a disorder of the ligaments in the hands and wrists that causes pain, inflammation and numbness. The National Institute for Occupational Health and Safety estimates that close to half of all office workers in the U.S. are at risk for Carpel Tunnel Syndrome or other cumulative trauma disorders (CTD). CTD refers to a family of injuries or symptoms that gradually hinder hand movement as a result of performing repetitive tasks.

About 4.4 million people in the U.S. suffer from various computer-related disorders. Dubbed "the industrial disease of the information age," CTDs are the leading cause of injury, productivity loss and financial strain on small businesses, costing hundreds of thousands of dollars a year in work-related injuries.

In recent years, the computer industry has attempted to decrease the number of CTD-related injuries by developing ergonomically correct keyboards. Many of these keyboards have been introduced since 1992, and while they all claim to prevent and ease the discomfort associated with keyboard-related injuries, your best defense against such problems is taking frequent breaks from typing. "Many of these keyboards come with wrist rests so people can remember to take breaks," says Ted Selker, manager of user systems ergonomics research at the Alameden Research Center in San Jose, Calif. Selker adds that using the correct posture and frequently changing your sitting position can also make a world of difference.

Although the special keyboards can be helpful, they take some getting used to. The feel and comfort of the keyboard should be your main concern, not the name of the manufacturer. For those considering purchasing ergonomic keyboards, there are a few particularly worth mentioning:

The Kinesis Ergonomic Keyboard ($275; 800-4-KINESIS) is innovative in its design. Contoured to fit the shape and movement of the human hand, it includes a separate concave alphanumeric keypad for each hand, and there is a palm support With optional self-adhesive pads to reduce stress caused by extending the wrist. As with most ergonomic keyboards, no software is needed for the PC, but if you use a Macintosh or Sun workstation, you'll need a $149 adapter box.

The Flexpro Keyboard from Keytronics Corp. ($179; 800-262-6006) literally can be split in half to create two demi-boards for user comfort. It has a built-in angled wrist rest that moves horizontally along the main key area for comfortable support.

Microsoft's Natural Keyboard ($99.95; 800-426-9400) is on the low-end in price and offers basic features. The keys are marked with icons to make using Windows easier. It also comes with built-in wrist rests, and the keyboard's height is adjustable.

Remember, there are ergonomically correct keyboards for almost any budget. Use price, durability, comfort and tech support to make your choice.