Anatomy of the Feet

Nearly one-fourth of all bones in the human body are in the feet. The foot is a complex, flexible structure that contains bones, joints, and more than 100 muscles, tendons and ligaments, all working together to enable movement and balance.

The foot is divided into three sections, the forefoot, the midfoot and the hindfoot. The forefoot has five toes (14 phalanges) and five longer bones (metatarsals). One phalanx of each of the five toes connects to one of the five metatarsals. Each of the four lesser digits, or smaller toes, contains three joints.

What are Plantar Warts?

Plantar warts (verruca plantaris) are small, rough growths that appear on the bottom of the foot, typically the balls or heels, or between toes. Although they aren’t usually a serious health concern, plantar warts may cause discomfort or pain.

Causes and Risk Factors

Plantar warts are a common skin infection caused by the human papillomavirus (HPV), which can enter through tiny breaks or cuts in the skin on the bottom of the foot. Plantar warts may appear from two to six months after HPV exposure.

Anyone can get plantar warts; however, some have a higher risk of developing this condition:

  • Children and teens
  • Have an autoimmune disease or weakened immune system
  • Age 65 or older
  • Caucasians (white)
  • Have had plantar warts before
  • Walking barefoot in locker rooms, swimming pools, or other areas where HPV is common

How are Plantar Warts Spread?

Plantar warts are contagious and spread from direct contact with HPV, through skin-to-skin contact, touching your plantar wart to another area of your body, sharing items like socks or shoes, or stepping on infected surfaces—especially when warm and wet. To avoid HPV exposure, always wear flip flops or shoes when using a gym, pool, sauna, steam room, or other public areas.

Symptoms of a Plantar Wart

Although similar in appearance to other warts, plantar warts exist deeper under the skin.

Symptoms include:

  • Small, rough growth with a thick surface, with a cauliflower-like texture
  • Pain, tenderness or discomfort when standing or walking
  • Cluster of growths (mosaic wart) on the sole of the foot
  • Growth that interrupts the normal ridges and lines in the ridges of skin
  • Black or brown pinpoints or dots (wart seeds), which are small, dried blood clots
  • Discoloration (dark pink, yellow, brown, purple or gray)
  • On dark skin, the growth may be lighter than surrounding, unaffected skin
  • Callus (pad of hard, thickened skin) over the area where a plantar wart has grown inward
  • Bleeding

When to See Your Podiatrist

If your attempts to treat the wart yourself have failed, or you experience any of the following, it is important to seek medical treatment immediately.

See your healthcare provider if:

  • You have diabetes or another condition that causes poor blood flow or lack of feeling in the feet
  • Your immune system is weakened from immune-suppressing drugs, HIV/AIDS, or an immune system disorder
  • The plantar wart is bleeding or changes in color or shape
  • The plantar wart multiplies or returns after clearing for a period of time
  • Pain increases or interferes with daily activities
  • You are unsure if the growth is a plantar wart

Treatment for Plantar Warts

Although your plantar warts may go away on their own in one to two years, once your immune system fights off the virus, you may want to contact your physician for treatment to avoid spreading and relieve pain.

Depending on the severity of your plantar wart, your podiatrist may recommend one of the following:

Topical medicine—Application of a liquid medicine causes a blister to form under the plantar wart, cutting off the blood supply

Cryotherapy—Extreme cold is applied to freeze and destroy the plantar wart

Immunotherapy—Diphencyprone (DCP) or another topical chemical is used to create mild allergic reaction that makes the plantar wart go away

Laser treatment—A laser light is used to heat and destroy the tiny blood vessels inside the plantar wart by cutting off its blood supply

Electrocautery—An electric current is used to burn the planter warts off

Surgical removal—After numbing the area with a local anesthetic, a sharp surgical knife (scalpel) is used to cut around the wart before pulling it out with a small scoop (curette) or tweezers