Ankle bumps

In the last five years I have developed unusual swelling, fat pads?, around both ankles.  I was told that it is not lymphedema.  There is no pain involved and no previous trauma.  The lumps are somewhat hard to the touch.  I've seen 6 doctors about this and NO ONE can figure out why this is happening!  They are unsightly and I'm embarrased by their appearance.  I am not overweight.

Does anyone have any suggestions as to what this could be?