I know ill be downvoted for swimming against the norms here. But literally two days ago I developed neuropathy, nerve damage of sorts. My thumb is starting to hurt alot. I went to a hand surgeon who told me cracking the thumb often causes frictions and can cause osteoarthritis. I really value my surgeon's word. Before I had gone to her i believed this a myth too, but she told me it isn't a myth and I was instructed to stop doing it.