Texting Thumb: It Might Get Worse

So picture this: it’s getting late in the workday, around 3, and you start writing a long text to the distant acquaintance who won’t stop bugging you, trying to get you to go with her to a Meetup of some group that you are totally not into and wish to avoid at all costs. About halfway through, when you get to the part about the doors not working on the train (though you’re on a bus, and it’s working just fine), you might notice, if you direct your attention to them for a moment, that your thumbs feel tired. And no wonder, they’ve been working hard all day.

Indeed they always have, for our multiple millions of years as a manually dextrous species. Just look at the great mass of muscles at the very base of your thumb. That muscle mass makes up much of the “heel” of your hand. Deep beneath those muscles are the joints that make up the thumb. Those joints are held together by cords and sheets of soft tissue—the ligaments of the thumb. These muscles, ligaments and joints are in motion much of the day, every day, engaged in the repetitive up-and-down motions of your thumb on your smartphone, and subject to forces emanating from the many small collisions of your thumb tip against the screen.

In hardworking hands, there’s not much recovery time for those thumbs, which need to rest and repair from all the accumulated micro-trauma of keeping up with a thousand Facebook friends. Yes, that’s absolutely a real thing—all those joint structures, hard and soft, have to undergo routine repair every day. If the physical recovery isn’t sufficient, and there’s still unhealed micro-injury the next day by the time you pick up that phone again (new cat meme?? Yes please!!!), then your thumb is starting the process of accumulating a “repetitive strain” injury. After enough accumulated injury to ligaments, muscles and other associated joint structures, you can start to feel it—it becomes a painful disorder. This is what we know as texting thumb.

It was bad enough when the problem was just heavy keypad use. But now there are additional tasks for the thumb when using a smartphone—particularly when using it one-handed, as many people do. We swipe—right, left, up, down. And often we press a Home button. That button is especially vexing for the thumb, because it's located so far down the phone—you have to bend your thumb in the direction of your little finger. I give smartphone makers lots of credit for leveraging the immense capabilities of our hands in order to drive the uses of their products; but I also want to call out the awkwardness of tasks like this. Awkward postures, i.e. with one or more joints near the limits of their ranges of motion, are well known to raise the risk of repetitive strain injury.

Not only that, but Home buttons are on the way out in newer phones. Apple’s latest as of now, the X, doesn’t even have a “soft” button—you swipe up from the very bottom of the phone. So your thumb has to reach even further than before. At the same time, phones have gotten bigger, adding yet a greater distance your thumb has to travel.

Given all this, unfortunately, I expect to hear of more repetitive-use thumb injuries, and I expect those injuries will be a bit more extensive, i.e. will involve more structures in the thumb.

There are at least 2 billion smartphone owners in the world, as of now. They will need their 4 billion thumbs. What can you do, as one of those users, to prevent or limit this type of injury?

• Take breaks and let your thumbs relax; shake them out gently.

• Consider getting a smaller phone, if you're not wedded to that giant screen.

• Use two hands sometimes, and try alternating fingers for some phone tasks.

• Use dictation capabilities when possible.

And just maybe, go and cringe your way through that Meetup anyway. It’ll give you a break from your screen, at least.