Though often harmless, plantar warts are often treated because they can be painful (or at least irritating). They are noncancerous growths that normally occur on three areas of the feet: on the plantar surface (also called the sole), ball, or heel. They often develop into the deeper skin layers because they are “pushed in” by the pressure from walking and standing.
If not treated, some plantar warts grow bigger – sometimes as big one inch in circumference. Untreated plantar warts may also multiply into clusters. Some severe plantar warts even cause posture problems that cause leg pain and/or back pain.
What are the symptoms of plantar warts?
Plantar warts are fairly easy to spot. They are usually brown or gray, spongy, and rough. Most warts have darker pinpoints, which are actually very small capillaries supplying the warts blood. Do not expect to see the “whole” wart – the part that you can see on the skin surface is actually just a small fraction of the complete wart. The part of the wart deep in the skin is more less than two times as big as the part on the surface.Most patients feel some degree of pain when pressure is applied on the warts, such as when standing. Most patients also complain of discomfort – they feel a stone-like lump in their shoes because of the wart.
What causes plantar warts?
Plantar warts are caused by the human papillomavirus (more commonly referred to as HPV). The HPV enters the feet through tiny breaks and cuts and breaks in your skin. It typically dies within one or two years, after which the warts vanish. Many doctors recommend having the warts removed, though, because they can cause discomfort. The American Podiatric Medical Association says that children and young adults are especially prone to plantar warts. Also at risk are people who often walk barefoot in moist places, such as locker rooms or common comfort rooms. People who often use public swimming pools can also be susceptible.HPV only survives when antibodies are not able to destroy them. People with weak immune systems are likely to develop plantar warts.
How to diagnose?
A physical exam is oftentimes all that is needed to diagnose plantar warts, which look unique and are easy to distinguish. Some doctors may require a skin biopsy, though, for further testing. The doctor may scrape skin cells from the plantar wart for evaluation.
Plantar Warts Treatment
There are many treatments available for the treatment of plantar warts. No single therapy is so effective that it has eliminated the use of all others. Ultimately, all treatments rely on the patient’s immune system to recognize the wart virus proteins and to produce an immune response that will rid the body of this annoying problem.
Over the Counter Treatments
Traditional treatment usually involves application of a mild acid such as salicylic, dichloroacetic, or cantharidin acid to the plantar warts. These mild acids effective kill HPV without destroying surrounding cells. Cantharidin (aka beetle juice) is painted onto the plantar warts and then covered with clear tape. This procedure causes blistering of the skin beneath the plantar warts, lifting off the warts from the skin. Note, however, that the Food and Drug Administration has not yet approved cantharadin for warts treatment. Some doctors may be hesitant to use it. Also, some doctors prescribe topical cream compounded by a pharmacy. This treatment has to be applied twice a day, is messy, sometimes expensive, and requires multiple visits to the office to have the site debrided/shaved. It can take several months for the compound to work.
Lasers are effective and usually do not leave any scars. Traditionally, laser treatment had to be performed in a hospital or clinic as they involved the administration of local anesthesia. However, Dr. Griffin now offers Cutera GenesisPlus laser treatment that offers the power needed to effectively eliminate warts without the traditional pain and discomfort of the old CO2 lasers.
Cryosurgery for Plantar Warts
Another treatment option is cryotherapy. The warts are frozen using sodium nitride (or other cold solutions), which then wipes out the virus, causing the plantar warts to blacken and eventually fall off. This option is usually very painful and may require local anesthetic injection.
Surgical Excision (removal)
After injecting a local anesthetic, the physician uses a scaplel and a curette to remove the wart. This technique is more likely than topicals and laser to cause a scar. (Note: The excision of warts is not recommended since the surgery may leave a painful scar and it is common for warts to return in the scar tissue.) Surgical removal is often not recommended, especially when there are multiple, large lesions.
For plantar warts that are resistant to treatment, Dr. Griffin may presctribe immunotherapy in which your body is taught to reject foreign substances (ie. warts). This treatment is painless but results take a few months.
Prevention and Prognosis
Plantar Warts Prevention
- Avoid walking barefoot, except on sandy beaches. Use shower thongs or sandals, particularly in public shower rooms.
- Change shoes and socks daily.
- Keep your feet clean and dry.
- Check children’s feet periodically.
- Avoid direct contact with warts from other people or from other parts of the body. Don’t touch warts on other people. To keep from spreading warts, don’t scratch them. Warts spread readily to small cuts and scratches.
- Do not ignore growths on, or changes in, your skin.
- Avoid sharing socks, shoes, and showering facilities.
- Protect the skin from injury, and wash hands frequently. Warts should be covered with waterproof tape in wet environments such as showers and swimming pools to avoid infecting yourself or others.
Plantar Warts Prognosis
- In up to 60% of cases, plantar warts exhibit “spontaneous remission.” This disappearance of the wart is because of the action of the body’s immune system.
- Untreated, plantar warts may grow up to an inch across and spread into clusters. Since certain HPV types are oncogenic (able to produce invasive malignant cancers), it is possible that plantar warts can rarely become invasive malignancies. Any wart-like lesion on the sole of the foot that does not resolve after appropriate therapy and continues to enlarge should be biopsied and examined by a pathologist.
- A painful scar on the sole of the foot can pose an even more severe problem, which is why surgery is not the first choice of treatment.
- Warts can grow back. This indicates a virus is still in the body and growing. However, this is not cause for undue alarm. The virus that causes plantar warts is relatively harmless and causes few problems. Warts can spread to other parts of the body, particularly if scratching a wart causes it to bleed. Blood from a wart contains the virus and can cause a new wart to grow in an area that it touches.
- Infection, pain, and scarring may result from overly aggressive home therapy penetrating beneath the skin surface. Pain can spread to other sites, and warts can be transmitted to others because of ineffective treatment.
Regardless of the home treatment or medical treatment used, a cure is not guaranteed. Warts may reappear at any time. Most therapies require several treatments and strict adherence to them. Work with your doctor to determine which therapy is right for you.