Just read this thread - hope you don't mind me chipping in.
Background.
We have not evolved for life on a hard, flat surface.
If you are a creationist we were not created for life on a hard. flat surface (unless you believe that there was concrete in the Garden of Eden). Some people find this absurdly simple concept difficult to grasp - but just think about it for a minute

.
Some people just don't adapt well to hard, flat surfaces. The OP may be one of them.
Trigger-point release will not work if every time you go back out onto the pavement you are re-irritating the problem.
Why has the problem suddenly come on after all this time?
My guess is simple ageing

. Up to the age of 30 we are, most of us, bomb-proof, after the age of 30 its downhill all the way!
Advice.
Try ditching your flat shoes (which I'm guessing you wear) and start to wear a small heel and see if that starts to help. Then try your trigger-point releases again.
David

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