Why do our joints crack?
Show answer & explanation
Answer: Gas bubbles pop in fluid
Tendons snap over bones — Wrong. While tendons can make sounds, the classic knuckle crack comes from gas bubbles.
Gas bubbles pop in fluid ✓ — Correct! Joints contain fluid with dissolved gases. Stretching the joint lowers pressure, causing gases to form a bubble that quickly collapses—pop! You must wait for gas to redissolve before cracking again. Studies show it doesn't cause arthritis!
Cartilage is breaking down — Wrong. Cracking isn't cartilage damage. It's harmless gas bubble popping in joint fluid.
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