I don’t like keyboard wrist supports, those long slips of fancy-padded rubber that sit directly in front of keyboard trays. Here is why.
The ideal position for your wrists and fingers to work in while typing should be “neutral,” neither flexed nor extended. This is best done with the wrists hovering ever so slightly above the keyboard. The fingers are able track slightly downward and find their way to the necessary keys. A keyboard tray will usually make the neutral position of the wrists easy to maintain.
In contrast, wrist supports force the user to plant his or her wrists in front of the keyboard while striking keys. If you look at both the fingers and the wrists during this activity, they are both forced into a good deal of extension. The person typing must lift each finger quite a bit to get from key to key. Although this may seem innocuous, the cumulative effect of lifting the fingers repetitively and keeping the wrists in slight extension for hours at a time can be devastating. Many people will develop strain in the forearm as the extensors become chronically overused.
I see many patients who have tennis elbow and wrist tendonitis directly caused by the faulty keyboard ergonomics described above. The overworked extensor muscles of the wrist and fingers originate at the elbow. Pain and strain can therefore manifest anywhere from the lateral aspect of the elbow all the way down to the top of the hand. In these cases, all of the medical intervention in the world will not permanently get rid of symptoms until the positions of the wrists and fingers are changed with typing.
If you have a rubber wrist guard, use it to rest your wrists while you are NOT typing. Better yet, throw it out and use a keyboard tray. Keep your wrists floating above the keyboard and type downward onto the keys.
I agree with the point about wrist rests forcing carpal extension and therefore exacerbation of carpal related RSI. However without the wrist support the bracheradial is forced to constantly support the free weight of the hand. If no arm rest is involved the shoulders, coracobrachialis are employed excessively, potentially leading to elbow and shoulder pain or RSI. Consequently the best practice is to support all of the joints or avoid typing all together. A carpal/palm wrist support, plus arm wrests and wrist pads in this case should help. In addition excessive pronation from using a flat keyboard may exacerbate RSI and elbow conditions. An ergonomic or split-halves keyboard (Kinesis brand) may also help. In my opinion the combination of excessive pronation, excessive carpal extension and constant lifting of the forearm can lead to tennis elbow, tendonitis and potentially tendinopathy due to constant remodelling of tendonous tissue in the joints. The science of tendinitis is pretty flimsy but I believe continual tendonosis may increase the chance of an unrelated tendon rupture. Consider distal bicep weakness leading to rupture as a result of excessive remodelling responses (collagen III production) triggered by inflammatory factors in the common interstitial spaces of the elbow.
Nice
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