User blog comment:Imhungry4444/One Piece Chapter 690 Review/@comment-4889755-20121201003744/@comment-3387274-20121205131913

he broke one of his fingers when he tried to grab his heart the first time and Vergo bashed it out. in order to keep his hand working, he swapped them round to put the innactive finger out of the way.

or at least that's the answer I'd give.

I imagine Oda would say that the tatoos came to be just as sarcastic as Law, and so being DEAH, came to life...