Boyd W. Haynes III, MD
When Orthopaedic Physicians (like myself) gather at a professional conference, we usually spend time discussing the latest innovations in joint replacement or spine surgery, new surgical techniques and groundbreaking biologic or pharmaceutical therapies. We typically don’t spend any time discussing or thinking about corns or calluses. However, these are exceedingly common foot maladies which deserve to be discussed for the patients that have them. In this article, I will describe the two issues, how they are diagnosed and treated.
Have you ever started wearing a pair of shoes that rubbed your foot the wrong way or put extra pressure on one area? Perhaps the shoes were too loose or too tight. Maybe you have a bunion or hammertoe which makes it hard for you to find shoes that fit well, so the leather is tight over those areas. If you are like most people, you probably wore the shoes anyway, thinking you would “break them in” over time. You may have quickly developed a blister on your toe or the bottom of your foot, or instead, developed a thickened patch of rough skin called a hyperkeratosis. With time and continued wear of those shoes, the hyperkeratosis may develop into either a corn or callus. While the causes are similar, corns and calluses do have their differences.
Corns can develop at any age, but tend to be seen most after the age of 65. There are two types of corn, hard and soft. A hard corn, medically known as a clavi or heloma, is a small, usually round or cone-shaped, lump of thickened tissue which may look dry, translucent or waxy. Hard corns are seen on the tops of the toes, bottom of the feet at the ball of the foot, or on the outside of the fifth toe. A soft corn (heloma molle) typically is white, wet and found between the toes. Because of their moist environment and characteristics, they can easily become infected. Both types of corns are painful, but the soft kind can be especially so.
A Callus is also an area of thickened skin, but it is flattened and often much larger in size, for example, covering the underside of the big toe or the ball of the foot. They may be hard or soft, white and flaky or thick and yellowish-colored. Calluses are not painful like corns, but can cause a burning sensation locally when forming or irritated by footwear.
It is easier to prevent corns and calluses than to heal them. Always buy properly fitting shoes that don’t rub or fit any area of the foot too tightly. If you have foot abnormalities, consult your physician about any areas that may be causing you concern.
At-home treatments for corns and calluses abound and can be found at any corner drug store. Ointments, salves, patches or other topicals will contain salicylic acid, the same compound used to treat warts, acne, seborrhea and other skin conditions. Salicylic acid is also used to make aspirin, the wonder drug. The acid breaks down proteins in the skin, causing rapid cell turnover. This skin regeneration results in peeling, dry skin layers which then can be easily removed, making the callus or corn less thick and/or painful. This treatment is often successful when used consistently and according to the manufacturer’s directions.
People who have diabetes or other diseases which hamper blood circulation and those with extremely sensitive or fragile skin should not use salicylic acid preparations and should see a physician for treatment of corns or calluses. Anyone who has a corn or callus that is red, swollen, and infected (with pus) should see a physician immediately for treatment.
When at-home treatment is not successful, a physician should be consulted. Your Primary Care Physician or Podiatrist will assess the corn or callus and recommend further treatment. Diagnosis will be made by a physical examination and asking the patient questions. No diagnostic x-rays will be needed for the corn or callus, but may be ordered to uncover underlying anatomical issues. In the physician’s office, most corns or calluses can be trimmed with a scalpel to remove much of the thickened skin. Orthotics, such as shoe lifts, inserts or padding may be ordered to help make shoes more comfortable and safely wearable.
Rarely, corns may require surgery to correct boney abnormalities underneath the skin, which are continuing to cause the corn. That is usually when I am called into action. I surgically can repair underlying conditions of the foot, such as hammertoe, mallet toe, claw toe, bunions, bunionettes, etc. which cause the foot to rub against the shoe, causing the development of the corn. Sometimes, all that is required is a shaving of the bone under the corn, to help the area be less prominent and less likely to rub or press against the shoe. All of these surgeries are done on an outpatient basis and are mostly successful at correcting the problem.
Corns and calluses are not in the slightest bit sexy or medically life-altering insofar as Orthopaedic conditions go. You won’t be seeing a TV or movie surgeon in the hospital, anxiously conferring with a patient’s weeping family about the best way to surgically remove a corn or pare down a callus. But aren’t you thankful that some medical conditions are just plain easy to repair without a lot of fuss?