Been facing the same sorts of issues for 20+ years. You've got a good handle on the issues/concerns.

Mine is totally random, sometimes brought on by too much physical exertion, sometimes by too much seat time in a car, sometimes by absolutely nothing that I can see. I've also had it totally disappear for several years. Pain can vary from very minor to totally debilitating. Like you I've noticed that early in the day it can be pretty minor but by the end of the day it can be pretty major.

My guess is the randomness is caused by the size/shape of the passageway where the nerve is being irritated. Different activities or stimulus cause varying amounts of inflammation and widely varying amounts of pain.

Ibuprofen has proven very effective for me but I'm trying to resist using it as much as possible.

I think its all just part of the inevitable aging process.

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