Conway McLean, DPM, Journal columnist

When someone is referred to as being only skin deep, it’s usually considered a derogatory term, but this is unfair. Our skin is an amazing structure, capable of a multitude of vital functions, reflecting many aspects of general health. Maintaining skin health is critically important to our well-being.

Skin is susceptible to all manner of problems from simple trauma to innumerable skin conditions. Some are due to auto-immune diseases, in which our skin, the largest organ in the body, becomes a target of the immune system. But the important functions of skin go beyond the breadth of this article. Certainly, protection from bacterial invasion is a vital one.

Skin is often the recipient of excessive physical stress, as with someone performing a physical task repeatedly. It defends us via the process of keratinization, whereby the outer layers of skin produce callus. The production of callus material is a natural process, appreciated by your average carpenter, whose hands are lined with the material.

Callusing at the bottom of a foot is commonly encountered when either a bone is out of position, or the individual is performing physically stressful tasks. When occurring on the ball of the foot, excessive production of this keratin material over time will increase the pressure. A localized callus in this part of the foot can be quite symptomatic.

The soft tissues found at the toes are minimal, so there is little padding. Prolonged pressure here leads to a very different kind of problem. Although it is not a medical term, calluses here are typically referred to as a corn, simply a callus on a toe. Although the term sounds fairly innocuous, these lesions can have dire consequences. Some of these may be only annoying, while others can be limb threatening.

Because of the lack of padding around the joints of the toes, any sort of deformity, a hammer toe for example, can lead to increased pressure. Callus will be produced, a result of the chronicity of the problem. The toe is pressed upon by our shoes with each step, 10,000 steps a day, over the months and years of our lives.

An individual’s skin type will determine in many ways, the type of callus produced and the speed with which excess keratin is created. This is largely an inherited trait over which we have little control. Some people are callus formers while others are not, again exemplifying human variation.

Regardless of the character of the keratoma (the technical term for a callus), location is vitally important. When the site is the tip of the toe, the lack of soft tissue interposition produces a very focused callus, with skin breakdown under the callus a concerning complication. If the individual is a senior citizen, for example, less than optimal nerve function may prevent the individual from experiencing the appropriate symptoms, most importantly pain. Without this stimulus, inadequate care is too often provided.

Because the toe bones tend to be somewhat irregular (in contrast to finger bones), bumps and spurs are common. Frequently these will be in a position to poke or pressure the skin: eventually a callus is produced. Removing the bump of bone, a procedure which can be performed through tiny incisions, will result in resolution of the callus and pain relief.

Another common site for these painful lesions is on the side of the toe over the nearest joint. When this occurs at the inner side of the second toe, it’s often the result of a deviation in positioning of the great toe, as experienced with a bunion deformity. This is the culprit leading to increased pressure and not necessarily the second toe.

Wherever a callus may develop, if a nerve is running through the area, a significant and more intense pain will likely be noted. Also common is the development of inflammation of the soft tissues with pain and swelling developing. Or, as mentioned, skin breakdown may result, with the potential for infection. A critically important factor here is the cardiovascular status of the individual. Someone with heart disease and arterial disease will probably not have an adequate blood supply to the tissues, resulting in weaker skin and a greater likelihood of breakdown.

Some simple measures can be quite effective in the treatment of these lesions. Hundreds of different padding products are available for these painful digits. From the venerable moleskin to all matter of silicon products, even custom molded devices, the options are plentiful. But padding typically doesn’t correct the deformity, or remove the bone spur, and the root of the problem remains. Thus, these methods are palliative, not correcting the condition, but temporarily reducing symptoms.

Removing callus tissue is a time honored approach, although the methods for doing so can sometimes be brutal. The use of a razor blade is not recommended due to the high propensity for self-inflicted injury. Various technologies are used by the general public and the professional. Reducing the callus is an effective means of reducing pain, but the amount of relief will depend on the specifics of the tissues affected. Again, debriding the callus ( professional trimming ) reduces the pressure to the living tissues and should lead to less pain. But only temporarily since the situation producing the pressure remains.

Many Americans live with chronic pain. A plethora of causes exist for this discomfort, but when it’s due to a simple digital callus, the discomfort is usually not disabling. Yet, living with pain affects gait, as well as quality of life. The former has serious repercussions, altering function and eventually leading to symptoms from some other body part. Solutions are numerous, but living with pain should not be one of your options.

EDITOR’S NOTE: Dr. Conway McLean is a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at drcmclean@penmed.com.