Blackberry use 'can damage thumb'

Trendy handheld Blackberry devices could cause damage to users' thumbs, doctors are warning.
Sales of the £200 gadget, which can be used to email, page and phone, have boomed in recent years with celebrities such as David Beckham using them.

But US and UK doctors said repetitive use could cause arthritis or harm tendons in the thumb.

Research in Motion, which manufactures the Blackberry, said it would not comment on the claims.