The analogy to sports actually reminds me a great deal of embouchure dystonia, which afflicts musicians that play winds (both brass and wood). Nobody really kno

The analogy to sports actually reminds me a great deal of embouchure dystonia, which afflicts musicians that play winds (both brass and wood). Nobody really knows what the root cause is, but many players simply stop playing when it hits in full force. Looking at the wikipedia page linked in the article (for Focal Dystonia), it looks like it probably is the same thing in all of these cases, just varying degrees of severity.