It appears that a noted British doctor made up the condition and submitted it to the British Medical Journal in 1974, in response to reports, which she thought were a prank/hoax, of a condition called, “guitarist’s nipple”, which is or is alleged to be a chafed nipple from resting the guitar there.

Normally, I wouldn’t have cared, but I played cello when I was 9 and 10, before switching to trombone, so the hed made me want to read it.