Crossing the legs alot and sitting that way for long periods, can compress the peroneal nerve.
Another possibility is something in that knee is acting up and compressing the nerve.
If this continues or spreads to other nerves, I'd get checked for B12 levels, and see if you are getting low. Your reading should be at 400 or above. Do not accept "normal" as lab ranges in US are antiquated.
These are the most likely (common) causes.
The ice is a good idea. Only do 20 minutes at a time a couple of times a day...and if this is a minor thing, it will resolve.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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