Lots of Ganglion Cysts on top of foot and on hand?

I'm hoping I can get the answers I need here.  About 4 yrs ago, I had a ganglion cyst removed from the palm of my right hand at the base of my ring finger.  A few years ago, I found another one on the right hand on the middle finger in the middle joint.  Doesn't bother me so I left it alone.  Then about a year ago I got a lump on the top of my left foot that turned out to be ganglion also.  Had it removed in Oct.  Two months later another one appeared a little further up on the top of my foot.  Had it drained and steroid injected.  Three months later the same thing happened, but it was a bit bigger.  Had it drained, no steroid.  The next day it came back, but bigger than ever.  Had it removed three weeks ago.  It was sent to pathology and was just ganglion.  Now I have another one below where the other two were, but on the side of my foot.  My podiatrist thinks maybe there is something causing all these cysts, but doesn't know what.  I am hoping someone might have some ideas?  Please help, I'm tired of surgery and pain. Thanks.

[funnyfarm98]

I forgot to mention that I have had xrays, but not an MRI.  I also have had slight arthritis in my left shoulder, elbow, hip and knee for about 20 years and now also have pain in my ankles when sitting for awhile then getting back up to walk.  I am about 60 lbs overweight, don't know if all this is related or not, but thought I should include it just in case.  Thanks.