Any permanent way to get rid of a callous at the base of the big toe. really painful and keeps coming back after being scraped.

Not permanent, but..: Callosity is simply the body's way of protecting itself from continuing trauma by building up excess tissue at the area of trauma. Scraping can certainly reduce this build up, but it is a dynamic process and will return over time. Consider adding ammonium lactate lotion to slow the growth. It works by increasing the amount of moisture in the skin and dissolving aggregated skin cells.