Mouse Problem: Could a Computer Mouse Hurt Your Shoulder?

I’m sure there’s some reason the computer mouse became so ubiquitous. It was probably cheap to develop and manufacture, compared to other possible devices for navigating a graphical interface. It’s small; it’s usually reliable. However, while it may move a cursor around efficiently, I’m not enamored of the mouse from a physical health standpoint. In fact, I consider it to be an ergonomic nightmare, and over the years have noticed many patients with wrist, arm, shoulder and even neck pain that appeared to be caused at least partly by extensive mouse use.
 
Many computer-using patients consult with me for neck pain, and upper and mid-scapular pain (around the shoulder and sides of the shoulder blade. Tellingly, a common association is right-sided upper body pain in right-handed mouse users. This often suggests to me that it’s time to examine the relationship between mouse and human.
 
So I ask most of my patients who are desktop-computer users where their mouse is located. Typically it’s placed out to the side of the keyboard and well ahead of them. That may mean the user has to reach rather far forward toward the mouse. In turn, this can stress the rotator cuff, and even the neck and upper back. In addition, reaching to the side, with the palm turned down so as to contact the mouse buttons, may stress the muscles of the forearm and wrist. For someone who uses a computer daily, for several hours a day, we want less physical effort. Minimizing muscle and joint stress should lower the chance of developing a painful disorder, or assist in recovery from such a problem.
 
Several years ago, a research study showed that the least effort, i.e. the least muscular stress, was required when the mouse was placed directly in the front of the body. This will make sense to you if you try this: sit at a desk, and raise your hand with your elbow kept close to you. Let your arm relax, so your hand lowers on to the desk. Your hand will almost certainly flop over palm down. Now imagine a line that divides you symmetrically into right and left halves, i.e. your midline. Your hand is probably not far from your midline. That’s because this is a position of ease for the arm; that is, the joints of the shoulder naturally move into this position when you relax your muscles.
 
Now move your hand so it’s positioned right in front of your shoulder, and relax the hand and wrist again. Your hand will probably relax little-finger-side down. Finally, slide your hand way out to the side. This time your hand is more likely to relax palm-up. That’s fine, but if you then want to use a mouse, palm-down, your muscles will be working harder. This means that the least-stressed location for the joints and muscles of your arm, when using a mouse, is with your hand right in front of you.
 
There’s a problem though: where will the keyboard go? That needs to be centered in front of you too.
 
Laptops have solved this by containing the pointing device, either a trackpad or pointing stick between the keys, front and center to the user. Laptops do have their own ergonomic problems; but I keep hoping that standard desktop keyboards of the future will include a decent trackpad.
 
But for desktop computer users who are feeling victimized by a mouse, alternative pointing devices exist, and can often minimize the conflict between mouse and keyboard use. These include sophisticated joysticks, tablet-stylus combinations and roller bar mice. The last of these is positioned just in front of the keyboard, and is generally one of the more expensive options. But it may be worth the cost: all my patients who’ve switched to a roller bar mouse have told me they’re very satisfied with it, and feel much more comfortable than they do with a conventional mouse.
 
By the way, do you know how the computer industry measures the distance a mouse travels? They express it in units called “mickeys.” True.
 
To sum up, if your computer use is mouse-intensive, you might consider trying out some of the alternative pointing devices on the market. But at the very least, consider moving a conventional mouse closer to your own midline, whenever you’re using the mouse more than the keyboard.