Carpal Tunnel Syndrome - Prevention

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Innovative keyboard designs may reduce hand stress:

• Alternative geometry keyboards (Microsoft Natural Keyboard, Apple Adjustable Keyboard) allow the user to adjust and modify hand positions as well as adjust key tension. Most have a split or "slanted" keyboard that places the wrists at an angle. Studies suggest they are useful in promoting a neutral position for the wrist.
• The continuous passive motion (CPM) keyboard lifts and declines gently and automatically every three minutes to break tension on the hands and wrist. A report of a clerical worker with CTS who used this device found an overall improvement of 10 words per minute in the typing tests, a decrease in disability score and symptom severity, and an improvement in function.
• A keyless keyboard (orbiTouch) is an innovative device that uses two domes. The typist covers the domes with his or her hands and slides them into different positions that represent letters.

Reducing Force from Hand Tools

The force placed on the fingers, hands, and wrists by a repetitive task is an important contributor to CTS. To alleviate the effect of force on the wrist, tools and tasks should be designed so that the wrist position is the same as it would be if the arms dangled in a relaxed manner at the sides.

• No task should require the wrist to deviate from side to side or to remain flexed or highly extended for long periods.
• The handles of hand tools such as screwdrivers, scrapers, paint brushes, and buffers should be designed so that the force of the worker's grip is distributed across the muscle between the base of the thumb and the little finger, not just in the center of the palm.
• People who need to hold any tools (including pencils and steering wheels) for long periods of time should grip them as loosely as possible.
• In order to apply force appropriately, the ability to feel an object is extremely important. Tools with textured handles are helpful.
• If possible, people should avoid working at low temperatures, which reduces sensation in hands and fingers.
• Power tools and machines should be designed to minimize vibrations.
• Wearing thick gloves, when possible, may lessen the shock transmitted to the hands and wrists. One 2001 study found, however, that wearing gel-padded gloves clearly increased comfort but did not actually protect against compression-induced CTS.