A wart is a lesion that grows in the skin. Often mistaken for a corn or callus, its distinguishing characteristic is a black dot in the middle of a hard lump of skin. Warts can appear anywhere; those that grow on the sole of the foot are called plantar warts and tend to be hard and flat. Warts that grow on the top of the foot tend to be softer and fleshier.
Warts can potentially grow to more than an inch in size and can extend into clusters called mosaic warts. Some warts are painless, but plantar warts that develop on the heel or ball of the foot can create pain on weight-bearing.
The human papillomavirus, or HPV, is the most frequent cause of warts. The virus is contagious and enters the body through cuts and abrasions. Plantar warts can affect anyone but are more common in youth between the ages of 12 and 16; the chance for HPV infection increases in students living in dormitories or people sharing communal showers. HPV is often contracted through shared bathing facilities such as in a gym or dormitory and by walking barefoot on unclean surfaces.
Prevention includes keeping feet clean and dry, daily changing shoes and socks, and avoiding barefoot walking. If a lesion appears, consult a podiatrist to ensure it is not something more serious. Avoid self-treatment with over-the-counter solutions because it is too easy to damage healthy skin. Outpatient procedures to remove the wart include laser, cryotherapy, and surgical removal.
