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Discover what is happening when you crack your knuckles. For starters, your knuckles don't crack: they pop.Key facts
- Your knuckles do not crack - they pop!
- The noise is the bursting of a gassy bubble, formed when the space between your bones increases.
- A lifetime of cracking knuckles can be dangerous, causing swelling to your joints.
- Swelling to the joints in the hand can lead to a loss of gripping strength.
Transcript
Why do knuckles crack?
For starters, your knuckles don't crack, they pop.
The noise comes from the space between your bones.
Scientists think that when you increase this space your knuckle swells as a bubble of gas is formed.
And the sound of a knuckle cracking is actually the bursting of this gassy bubble.
But …
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