Do you really need to stop cracking?We Asked: John Indalecio, a hand therapist at the Hospital for Special Surgery in New York
The Answer: There is no compelling scientific evidence that cracking your knuckles causes arthritis. But a long-standing habit could affect joint function down the road. Here's what's going on.
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A joint is the point at which two (or more) bones meet. Ligaments connect the bones to one another, and a joint capsule surrounds the whole thing. It is filled with a natural lubricant called synovial fluid that helps the joint move smoothly. When you make the motion to crack your knuckles, the joint is pulled apart, expanding the capsule. This decreases the pressure inside the capsule, forcing gasses dissolved in the synovial fluid to release into the space to equalize it. That rush of gas causes the pop! sound-so satisfying to you, so annoying to everyone else in the room. It's like popping the top on a can of soda.
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