If you haven't injured it this could be the start of osteoarthritis which can manifest gradually or suddenly.
You see the tendons at the bottom of your wrist, what ever muscle is conected to thoes
type in < then 3 together in a word
A Monkey's Fist knot is quite easy to tie. This video explains it well: http://www.youtube.com/watch?v=Q7oyN4LoQfQ
Well, kind of but it is hard and it kind of hurts if you try really hard.
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