Plantar warts are benign (noncancerous) growths that occur on the sole, heel, or ball of the foot. Most plantar warts are diagnosed based on their appearance. They are generally rough and spongy, and most are gray, brown, or yellow with dark pinpoints—these are typically tiny capillaries that supply blood to the wart.

Plantar warts can occur when the human papillomavirus (HPV) invades the body through the skin on the bottom of the feet typically through cuts or breaks. The virus often is present on contaminated surfaces, such as the tile floors of public locker rooms, showers, and swimming pools.

Some individuals are more prone to the virus that causes plantar warts than other people. Risk factors include:

• Repeated HPV exposure. For example, walking barefoot in public locker rooms and common public areas.

• Having a weakened immune system.

In some cases, the virus can be transmitted to the feet from other areas of the body. This is called remote location seeding.

When first diagnosed, individuals often feel a “lump” on the bottom of the foot when standing, similar to having a stone in the shoe. If left untreated, plantar warts can grow up to 1 inch in circumference and may spread into clusters (called mosaic warts). In severe cases, they cause a change in gait or posture that results in leg or back pain.

If you suffer from plantar warts, visit your podiatrist to find effective treatment options for you.