A hard, whitish patch on a child’s sole can be a callus, a corn, or a plantar wart. They can look alike, but their causes and care differ. This article covers how to tell them apart, home care, and when to see a doctor.
Why It Happens
Calluses and corns are thought of as the skin’s response to repeated pressure or friction, which thickens the outer layer. The 2002 AAFP review lists poorly fitting shoes, foot deformities, and high activity levels as major causes. A callus is broad and fairly even in thickness, while a corn has a central cone-shaped core of keratin and tends to hurt when pressed. A plantar wart is different: it is a lesion caused by a human papillomavirus (HPV) infection, not by pressure.
According to the 2018 AAFP review, plantar warts are most common in childhood, affecting about 20% of children aged 4 to 12, and roughly two-thirds go away on their own within two years.
How It Differs by Age
Children who are just learning to walk have thick fat pads and low body weight, so calluses are uncommon. In school-age children, long hours in sneakers, cleats, or ill-fitting shoes can cause corns over the ball of the foot or toe joints. Warts are often picked up in barefoot settings such as pools and gym floors. Younger children may not describe pain and instead limp, or avoid putting weight on the foot.
Care at Home
Telling them apart comes first. AAFP material explains that when the surface is gently pared, a wart shows tiny pinpoint blood vessels (which look like black dots) and interrupts the normal skin lines, while calluses and corns keep those lines. Corns are described as more tender with direct pressure, while warts are more tender when squeezed from the sides.
For calluses and corns, reducing pressure is the key. The 2018 AAFP review notes that over-the-counter salicylic acid gives short-term benefit, while pads and inserts that spread pressure evenly give longer-term benefit. Choose shoes with room across the forefoot and toes, and soaking in warm water followed by gentle rubbing can help. For plantar warts, over-the-counter salicylic acid and freezing-type products are described as about equally effective, though treatment may take around 6-12 weeks. Keep products away from the mouth and check with a pharmacist or doctor before using them on a child.
Common Misunderstandings
First, that cutting the spot out with a blade helps; a child can be hurt or the area infected, so this is not advised. Second, that every hard spot is a corn; it may be a wart, which can spread. Third, that a wart must be removed right away; many go away on their own, so waiting is a reasonable choice if it doesn’t hurt. Fourth, that once gone it won’t return; corns can return if pressure continues, and warts can return with the same barefoot exposures.
Signs That Need Emergency Care Right Away
Go to the emergency room right away if the sole becomes red, swollen, and hot with pus, a red streak spreads toward the ankle, or your child has a fever and cannot put any weight on the foot. If it is not an emergency, the AAD advises seeing a board-certified dermatologist if you aren’t sure what is causing the lesion, if it is very painful, or if the person has diabetes. If a wart keeps spreading, hasn’t improved after months of treatment, or changes how your child walks, see your pediatrician or a dermatologist. Consider talking with a pediatrician if you are unsure. This information reflects general guidance for the United States; if you live elsewhere, check with a local pediatrician. This information isn’t a diagnostic tool and doesn’t replace advice from a medical professional.