Ok I've had this for about a year now and I've searched and searched and can never find an answer on what I have. I've tried a bunch of different types of lotion/creams and it somehow only works temporary.
Anyways my big toe and the little one next to it is discolored. It's dark, dry and rough to the touch. Its like all on the knuckle parts of the toe and its only those 2 toes. For some reason its on the side of where my big toe is but its not as dry as it used to be just discolored and theres another one thats like a line. Sorry for some weird explanation but its kinda hard to try and explain it. And this is only on my left feet.
Sounds like maybe a circulation problem. Try massaging or using a foot bath that circulates bubbles and see if that helps. You should also have a doctor check it out just to make sure you don't have any underlying problems.