Corns: Symptoms, Causes and Treatments

Heloma durum (hard corns) are the most common types of corn. They are formed when the skin has tried to protect itself against friction or pressure and usually develop on the tops of the toes and along the sides of the feet. Hard corns appear as small, pale or yellow areas of raised, hardened skin and can also look shiny and polished. The centre is surrounded by hardened skin. Corns are often caused by ill fitting shoes or toe deformities such as hammertoe. With this, the toes curl downwards so that the middle parts of the toe stick up and rubs against the shoe. To compensate for this, the skin thickens where the extra pressure contacts the toe. Surgery is often required as a permanent solution because hard corns usually occur as a result of toe deformities. The only other option is to cut or burn them off but they will recur.

Heloma molle (soft corns) also form as a response to excessive pressure/friction.
They occur when one of the toe bones is slightly too wide although people with normal toe bones can also develop soft corns. Soft corns have a white, rubbery appearance with an indented centre. Sweat and moisture maintain the rubbery appearance. Advice for individuals suffering with soft corns would be to buy wider shoes. Where this is unsuccessful, a surgical approach may be used.

Heloma millare (seed corns) are similar to hard corns but smaller and shallower appearing as crater like pits They can be found with overlying calloused skin. There can be a single corn or in groups and are usually found around the metatarsals but can be seen on the heel or midfoot. Seed corns are painful and are usually linked with dry skin. Treatment is to remove the seed corns and apply an emollient cream which protects the surrounding area preventing it from drying out. A follow up is usually required as seed corns often multiply.

Subungal corns can form due to repeated pressure on the nail plate. They can be difficult to see but can be diagnosed from the pressure on the nail which will be painful. Subungal corns are very difficult to treat whilst the nail is still in place so the nail must be partly or wholly removed. The corn can then be removed with a scalpel. A caustic agent can be applied to the area to make sure that the corn tissue has been destroyed. Patients should be reviewed every two to three weeks.