Using both thumbs to enter data on tiny keyboards. Small video game consoles, smartphones and texting created the thumb culture, and the activity can become painful. De Quervain's Disease is inflammation of the tendons that extend to the wrist, a malady that in the past was called "washerwoman's sprain." See Nintendo thumb
, medical conditions
and KALQ keyboard
The Thumbs Do the Typing
BlackBerry physical keyboards popularized the thumb culture, which was followed by touchscreen keyboards. It is amazing how fast some people can type using both thumbs.