Something that from its surroundings is said to stick out like a thumb, because a throbbing thumb is often vividly red. And more and more Americans' thumbs are quite literally sticking out in just this way. So many that in their medical , orthopedic specialists are describing an of sore thumbs.

It's all because of personal computers such as BlackBerries, Palm-brand handhelds, and certain cellphones. bigger than a credit card, these little devices have itsy-bitsy keyboards. The most popular way to type a message while them is to use one's thumbs. And by the , over and over again, day and night, Americans are doing just that – checking and sending their e-mails.

The result can be a painful, , or mini-version of carpal tunnel and tendinitis that used to affect only those who repeatedly larger machines. The Washington Post newspaper, which recently wrote about thumb pain, illustrated the story with a photograph of three White House staff members standing side by side at one of President Bush's speaking . All three where thumbing away on their BlackBerries. A similar photo of ordinary could have been taken in cafes and waiting rooms across America. As with a drinking problem, is the only proven remedy. And by all accounts, texting on one's palm-size personal device can be just as hard a habit to .

So while delightfully convenient, handheld communications can exact an toll. But things could be worse. As the Post article points out, in Japan, teenagers are now referred to as the .