It may sound like a neat new gardening term, but if you’ve got a “BlackBerry thumb” it doesn’t mean you’re horticulturally talented.

The term has been coined to refer to the repetitive strain injury caused by constant typing on the small handheld devices known as personal digital assistants, or P-D-As. The BlackBerry is the iconic model with the catchy name, but it could be any of them. Sufferers experience pain and numbness in the thumbs and joints.

According to a recent study conducted by Microsoft in the United Kingdom, one-hundred-fifteen-thousand new cases of repetitive strain injuries of the upper limbs were reported for 2007, up from eighty-six-thousand cases the year before, over a thirty percent increase in only one year. The study identified several causes of such injuries and specifically singled out the increased usage of personal digital assistants.

The American Physical Therapy Association’s Occupational Health Special Interest Group confirmed the findings, noting that because the thumb is the least agile part of the hand but is the only digit used while typing on hand-held P-D-As, the chance for injury is significantly multiplied. And because P-D-As are now common in and out of the workplace, the number of injuries is even greater.

Doctors advise those with “BlackBerry thumb” to not work through the pain, but rather to limit the use of such technologies until the episode fully passes. If a text message is required, forget the drawn out response. A simple yes or no might help save those thumbs.