Ergonomics of Keyboard Use

We don’t think about simple, everyday repetitive, small-amplitude, movements as producing strain. Many times, we don’t realize that seemingly disparate activities are using the same muscle groups and adding to the “strain.” Pain is the body’s way of telling us that tissue injury is occurring. Pay attention to that signal—even if it occurs only transiently.

The first step in alleviating any musculoskeletal pain is to start with good posture and placement of your keyboard so that the angle at the elbow is bent at 90- to a 110-degree angle. Your arms need to be relaxed, wrists in a neutral position and fingers naturally curved and relaxed but not tightly curled (the “claw” is reserved for knife use when slicing onions in the kitchen).  Shoulders should be level and supporting the upper arm. Relaxed keyboarding really involves the entire upper extremity.

Pain while using the keyboard suggests that you are not in a relaxed neutral position. Deviation, or sideways twisting, of the wrists, either inward or outward, can result in wrist pain. If this is happening with keyboard use you may need to get a larger or smaller keyboard so that your wrists remain in neutral position while you type.

Resting elbows on the desk while typing results in reduced arm movement, and wrist movement is increased. This will result in strain on the muscles of the forearm with potential pain. Using wrist rests during typing also increases the work of the forearm muscles. A curled position of the fingers with the wrists bent either downward or upward puts a strain on the muscles and may result in irritation of the tendons at the elbow and forearm pain.

Pain in the hands can result if your fingers are tightly curled and your wrists either too elevated or bent downward. You require more effort from short muscles in the hands. This kind of strain can cause pain, irritation, and inflammation of tendons and muscles in the hands and fingers.

Special keyboard designs can help alleviate these problems—but no keyboard (no matter how expensive) can help if your workstation is not set up properly.  Our indexing software (and most word processing software) has resources for reducing the keystrokes required to accomplish many tasks.  Knowing what your software can do is important. There are also macro programs that reduce keystrokes.

Perhaps you’re thinking that you will simply use the mouse more. That can help, but any muscle and joint can be affected by “overuse,” so even mouse use can result in RSI (repetitive stress/strain injury).

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Editor’s note: This article is part of a series on occupational challenges for freelance folks who sit in front of computers most of the day. Look for more on the details of making your workplace human-body friendly from our resident indexer and DO, S. Anne Fifer.