I Came Across Info Not Too Long Agonand Now Can't

I came across info not too long agonand now can't find it. It was a medical condition where (if I'm remembering correctly) the muscle below collar bone swells and protrudes above collar bone - appearing as a swollen mass above collar bone. From repetitive use of arm/muscle. Does this sound familiar to you? Trying to figure out what that is called? And more info on it, please and thank you.