Foot discomfort is a common experience, and sometimes skin conditions can develop that are easily confused. Two such conditions, corns and plantar warts, often appear on the feet and can cause similar sensations. Understanding the distinctions between these frequently mistaken growths is helpful for identifying them.
Understanding Corns
A corn is a localized area of thickened skin that develops in response to repeated pressure or friction. This protective response aims to prevent the skin from breaking down due to irritation. Corns typically appear as small, hardened bumps, often with a dense central core.
The skin lines over a corn remain intact, flowing continuously across its surface. Corns commonly form on the tops or sides of toes, between the toes, or on the sole of the foot, particularly over bony prominences where shoes might rub. Ill-fitting footwear, such as shoes that are too tight or too loose, or foot deformities like hammer toes, are frequent causes of corn development.
Understanding Plantar Warts
A plantar wart is a non-cancerous skin growth on the sole of the foot caused by an infection with the human papillomavirus (HPV). The virus enters the skin through tiny cuts or breaks, often in warm, moist environments like public swimming pools or locker rooms. Plantar warts typically appear as flesh-colored, grainy, or rough patches of skin.
Due to the pressure from walking and standing, plantar warts often grow inward, appearing flat or slightly indented on the surface. A distinguishing feature is the presence of tiny black dots, which are pinpoint hemorrhages from clotted blood vessels that supply the wart. Unlike corns, the normal skin lines on the foot are disrupted around a plantar wart.
Key Distinguishing Features
Corns often have a hard, defined central core, with natural skin lines flowing uninterrupted across their surface. Plantar warts, in contrast, frequently display tiny black dots (dried blood vessels) and disrupt the normal pattern of skin lines around them.
Pain sensation also varies. Corns typically cause pain when direct pressure is applied. Plantar warts, however, tend to be more painful when squeezed from the sides.
The underlying cause is another differentiator. Corns develop as a physical response to repetitive friction or pressure, often from ill-fitting shoes or foot structure. Plantar warts, conversely, are caused by a viral infection from specific human papillomavirus (HPV) strains. This viral origin means plantar warts can be contagious, unlike corns.
Location on the foot also differs. Corns commonly form over bony prominences or areas subjected to concentrated friction, such as the tops of toes, between toes, or on the ball of the foot. Plantar warts can appear anywhere on the sole, though they are frequently found on weight-bearing areas like the heels or balls of the feet. A plantar wart may even be covered by a layer of thickened skin, resembling a callus.