The pain I had was caused by a number of things that attacked all at once and it including muscle pain. I was get the most awful you-wouldn't-even-wish-upon-your-worst-enemy cramping pain from toe to ankle for 20 minutes at a time. Afterwards, I felt like I was hit by a semi and my foot would pulsate in pain for days afterwards. The sensitivity in my feet was muscle, not joint. I couldn't even sleep with a sheet over my feet. It was too heavy. Aside from the psoriatic arthritis, they said they found mechanical problems, neuroma, raynauds syndrome, metarsil problems, etc. (I probably spelled all that wrong, forgive me. )
It was a combination of FIXING the mechanical issues as well as stretching and exercising the foot and calf muscles (deep deep stretches and massages), muscle relaxants, and about 2 years of time before I felt like I was semi-mobile (though once I finally started the muscle relaxors, the level of pain dropped tremendously.)
When I was on Remicade and it helped the joints, that also helped alleviate the problems that still exist.
Good luck. Happy New Year.
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