Dave,
I am One who has a pretty good idea of just what You are going through.
Three years ago,this August,I had my left knee operated on. It is worse now,then ever.I have to exercise or walk every day to keep it mobile. Even so,it can go 'sour'any time,without warning. One day,I can do two miles on the track;the next day,it swells up,just walking to the track.
Two months ago,I had the worst one of my hands operated on for Carpal-Tunnel. I have a little more feeling in my fingers,but the strength has yet to return to my hand. I can't loosen the chuck on my hand drill,and can't open a medicine bottle. I won't have the other hand operated on.
I do not have any Arthritis in my legs,at all. It is only in my arms and hands,and shoulders, and neck.
Like You,I know that I have to keep pluggin',or I'll dry up and blow away.
Frank