Why do people crack their knuckles?

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Tags

1. #thought
2. #occurs
3. #knuckles
4. #points
5. #seeking
6. #inflame
7. #knuckle
8. #relief
9. #reasons
10. #tension
11. #about
12. #people
13. #numerous
14. #nervous
15. #percent
16. #commonly
17. #crack
18. #cause
19. #between
20. #cracking
21. #habit
22. #their
23. #arthritis
24. #include