What is drummer's palsy? The doctor thinks my 17-year old daughter may have this. It's from too much drumming with her garage band.

Tendonitis of the thumb tendons from overuse is called Drummer's palsy. The term was first used in 1891. This was a time when drumming was an actual occupation. It's likely that more than just using the hand over and over in the same motion causes the
tendon to tear. The person may have a bone spur, bony bump, or spike of bone under the tendon. As the tendon moves back and forth over the bone, friction occurs. The body responds to the friction with inflammation of the tendon (called tendonitis).

The usual cause of this condition is repeated and forceful work. These factors cause local stress in the tissues. Intensive repetitive activity or forceful use done on a daily basis doesn't allow the tissues a chance to recover.