Why are punches to the back of the head illegal?

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Tags

1. #injury
2. #spinal
3. #rabbit
4. #serious
5. #considered
6. #dangerous
7. #cervical
8. #damage
9. #because
10. #especially
11. #vertebrae
12. #which
13. #punch
14. #subsequently
15. #skull
16. #irreparable