EE WAS ATTEMPTING TO REMOVE SEVERAL BOLTS FROM A MOUNTING FLANGE BY HITTING ON FLANGE PLATE W/4 LB SLEDGEHAMMER. HIS FINGER WAS CAUGHT BTWN 1 OF THE BOLTS & THE HAMMER HANDLE AS HEAD OF HAMMER CONTACTED FLANGE PLATE. EE BELIEVES HAMMER HANDLE TILTED DOWN SHARPLY AFTER HEAD OF HAMMER CONTACTED FLANGE PLATE.