Plantar warts are a common viral skin infection on the bottom (plantar) side of your foot. About 10 percent of teenagers have plantar warts. Using a public shower or walking around a locker room in bare feet increases your risk for developing plantar warts.
Contrary to the old folk tale, you can’t get warts from touching a toad. Warts are caused by a virus that enters the body through a break in the skin. The virus grows in warm, moist environments, such as those created in a locker room or in your shoes when your feet sweat and moisture is trapped.
To reduce your risk of getting plantar warts, be sure to wear flip flops or sandals when you use a public locker room or shower. Use foot powders and change your socks frequently to keep your feet dry.
Plantar warts often spread to other areas of the foot, increase in size, and have “babies,” resulting in a cluster that resembles a mosaic.
Plantar warts can erupt anywhere on the sole of the foot. They may be difficult to distinguish from calluses. However, you may be able to see tiny black dots on the surface layer of a plantar wart. These are the ends of capillary blood vessels. Calluses have no blood vessels, usually resemble yellow candle wax, and are located only over weightbearing areas.
Plantar warts can be very painful and tender. Standing and walking push the warts flat. They grow up into the skin, making it feel like there’s a stone in your shoe.
Although plantar warts may eventually disappear by themselves, you should seek treatment if they are painful. Your foot and ankle orthopaedic surgeon may carefully trim the wart and apply a chemically treated dressing. The physician also may give you instructions for self-care. Salicylic acid patches, applied on a daily basis, and good foot hygiene, including regular use of a pumice stone, usually are effective. However, it may take several weeks for the wart to disappear completely.
If the wart is resistant to treatment, your physician may recommend an office procedure to remove it. After a local anesthetic is applied, the physician uses liquid nitrogen to freeze the wart and dissolve it. To avoid scarring or damaging other tissues, this method removes only the top portion of the wart. The treatment must be repeated regularly until the entire wart is dissolved. Alternatively, the physician can cut out (excise) the wart.