What Causes Severe Pain In The Toe?

I have occasional excruciating pain in my second to last toe on the left foot. It can be debilitating to walk. It comes infrequently and lasts several minutes to an hour or longer. It is not cramping, but flashes of extreme pain and warmth, and it is difficult to walk when it occurs. Nothing looks different when looking at the affected toe. I have not figured out anything that triggers this reaction - food, activity, etc. My shoes are comfortable and supportive - usually tennis shoes. It has occurred on and off for over ten years. I have never injured that toe and have never experienced problems with any others. I have no other chronic conditions that I am aware of with which this might be associated. Tonight it is lasting longer than usual.