Mousepads with Wrist Rests Can Be Harmful but Don’t Have To Be

Egads!!!!  Mousepads harmful?  And putting this information on this site?  Sam, what were you thinking?!!!
Well…  Ummm….  I was doing research on healthy workspaces and I came upon this recommendation from CUErgo (Cornell University’s Ergonomics Lab):

Don’t use a Wrist Rest – research has shown that using a wrist rest doubles the pressure inside the carpal tunnel, because the floor of the tunnel is a more flexible ligament that transmits external pressure changes directly into the carpal tunnel (the roof of the tunnel is bone so the pressure doesn’t get transmitted on through the hand). Indeed, one test for carpal tunnel syndrome (CTS), know as Tinel’s sign, simply involves tapping on the palmar surface of the wrist, which is enough to cause tingling and numbness in someone developing CTS.

That’s pretty straight-forward.  But then I stopped panicking and thought about this carefully.  I actually have had carpal tunnel syndrome (CTS) and know exactly what it feels like and know the tingling sensation they warn about through personal experience.  And they are right – IF you happen to put all of your weight on your wrists.
See, here’s the deal.  The Mayo Clinic tells us that:

Carpal tunnel syndrome occurs as a result of compression of the median nerve.

And that happens usually from two things:
  1. Bending your wrist while typing/mousing for extended periods of time.
  2. Putting pressure on your wrist by resting it on the wrist rest (duh!).
But that’s not how many of us use a mousepad with a wrist rest.  In fact we use the wrist rest as a guide that keeps our wrists straight (item number 1) without putting pressure or pinching the median nerve (item number 2).  Here’s a visual shown from DePaul University’s Ergonomics Lab:
Image From DePaul University's Ergonomics Lab
So an ergonomic mousepad with a wrist rest can work as a guide to avoid the wrong positions.  The shape will keep you from bending your hands too much to the left or right and the pad will keep you from bending your wrist at the wrong angle.
After reading the article, then thinking this through, I wanted to blog about it.  If you have The Pad or any other mousepad with a wrist rest please be careful.  You can use it correctly to reduce strain or, if you are not careful, you might accidentally increase your problem.