I got distracted doing a break for the kid's class one night. Was just doing a regular punch-through-a-rebreakable-board-on-top-of-some-bricks, and split my middle knuckle in half. I've had arthritis in that motherfucker for about 6 years. When I do bag work, can only do open hand and one or two-knuckle strikes.
But yeah, those guys were real fatties. Was semi-impressed by the finger tip break, though.