Why cracking your knuckles got a bad reputationFernandez has a suspicion about where the myth about knuckle cracking dangers emerged. And while a knuckle crack isn’t stinky, it is a reminder of our bodily functions—specifically the fluid and gas in our knuckles. Luckily, a side effect of knuckle cracking is not the bends—or even a case of arthritis. At the awards ceremony, Unger declared: “On my tombstone, I want it to say, ‘Here lies Don Unger, who finally has quit cracking his knuckles.’”A cracking debateStill, despite decades of research into knuckle cracking, one big question persists: When is that cracking sound actually created, Fernandez says. Some studies suggest the noise is made when the gas bubble is formed, he said.