People who do repetitive work with their hands may develop a number of different medical conditions. Some, like carpal tunnel syndrome, are fairly well known. Others, like De Quervain tendinitis are less so. You can read about the causes, symptoms, and treatments of De Quervain tendinitis in the National Library of Medicine's MedlinePlus Medical Encyclopedia:
Beware, though. If you hold your phone or tablet while
you browse the 4,000 articles available in the Encyclopedia, that's
exactly the sort of thing that might cause De Quervain tendinitis.