Feet get put through the works! From the moment you get out of bed until you next sit down, the feet are under constant stress and pressure. No wonder 18% (Springett et al., 2003) of workers experience painful calluses and corns.
Skin, also known as the epidermis, is the largest and most extensive organ of the human body. Depending on where on the body, the thickness of skin changes. The thickest skin is found on the soles of the feet which may begin to explain what a corn and callus is. Before diving into what those two are, let’s look at the function of skin. It is a dynamic and exciting part of the body which has a variety of functions. One of the main functions is to act as protection against physical, radiational, biological and chemical objects and agents. Additionally, it helps us maintain our body temperature, enables us to sense the world through touch, and allows us to communicate with the world around us. Clearly skin is a very important part of our lives, and the skin on our feet is the thickest part of all of this, which means we cannot neglect this area.
Now let’s break down corns and calluses. Usually found on the bony prominences of the feet and toes, corns are sharply demarcated areas of hyperkeratotic plaque. With a clear central core which dives deep into the skin, these formations can cause pain and inflammation. These often arise in response to a mechanical trauma and the foot is now just trying to protect itself. It can also form due to pressure and friction.
A callus is similar however, it does not have that clear central core. A callus is a more broad based lesion of hyperkeratotic plaque. The thickness tends to be more even which may spread across the heel or ball of the foot. These develop with friction and pressure but its the bodies lack of shedding and increased cell adhesion which is behind the formation of the callus.
What is the difference between the two?
There is not much difference between the two on a microscopic level, but on a larger, more human level, the corn has a deep seeded central cone which can be quite painful. Further, we can break down a corn into a hard, soft or seed corn. A hard corn is usually found near a bony prominence, a soft corn can be seen between toes and is usually softer, while a seed corn is normally found beneath the foot. A callus has that broadness and also contains accentuated skin lines which can be found anywhere the skin is exposed to friction and pressure.
What are the symptoms of corns and calluses?
Let’s break down the symptoms
Flaky, dry or waxy skin: corn or callus
Pain, redness and blisters: corn or callus
Hardened/thickened area of skin exposed to regular friction or pressure: corn or callus
Hard circular bump with irritated skin: more likely a corn
Painful raised region of skin: more likely a corn
Thick patch of skin with some discolouration: more likely a callus
Area of thicker skin with less sensation than surrounding skin: more likely a callus
What are the common causes of corns and calluses?
Corns and calluses are caused by an increase in mechanical pressure and the body responding to protect the area under pressure. Common increases in mechanical pressure include;
Wearing high heels
Wearing unsupportive shoes
Not wearing socks
Heavy weight lifting
Playing musical instruments
How are corns and calluses diagnosed?
As you can see, these two conditions aren’t so different and that’s why a foot health specialist should be consulted to determine the correct and most effective treatment. A foot health specialist can use a detailed history, visual and hands on assessment to determine what is happening, what has caused this and most importantly, how to treat and prevent this from returning. The key aspect of seeing a foot health specialist is that they can rule out other causes like warts, neuromas or gout.
What are the treatment options for corns and calluses?
As corns and calluses are not skin conditions, rather a response to mechanical impact the treatment can be simple and effective. The pain you feel is a result of pressure from the central keratin plug on skin nerve endings. The pain signals to your body that it is time for something to be done to protect your feet. Treatment has two options, surgical or conservative and within conservative is prevention. The main aim of these treatments is to reduce the pain and disability from the corns and calluses while also preventing complications.
Corn paring – This is the process whereby the foot health specialist removes the hyperkeratotic tissue gently, removing the central plug and decreasing the pressure on the nerve endings beneath the corn.
Callus paring – Similar to corn paring, the foot health specialist removes the hyperkeratotic tissue gently. This is the first part of the treatment with the second involving the necessary changes to footwear and factors which may cause the callus to return.
Topical keratolytic medication – These topical medications break down the build up of keratin on the skin and can also be used prior to corn paring to assist the process. Foot health specialists can advise on the most appropriate topical medication for you to use.
Ablative laser therapy – Can be used instead of paring where the carbon dioxide laser helps remove the hardened tissue with minimal thermal damage.
Mechanical changes – A foot health specialist will help determine what factors of your life could be maintaining and causing these lesions to develop and then help remove these factors. Working together to remove the causes helps prevent corns and calluses from returning.
The surgical removal of bony prominences or other primary causes of the lesions. The surgical method is only used if conservative treatment has failed.
How long do corns and calluses last?
A corn or callus does not disappear overnight, however they can slowly heal on their own if the aggravating or stress causing factor is removed. This may take weeks or months to heal. With the help from a foot health specialist, this process is sped up and you can see results from the moment you leave the treatment room. The length it takes to heal comes down to the changes made to footwear and lifestyle as if the area continues to be irritated, the corn or callus will grow back to protect that area again.
Can corns and calluses be prevented?
ABSOLUTELY! The best part about corns and calluses is that in the most part, they are preventable. Wearing supportive footwear and regularly checking your feet is the easiest way to prevent their development. Wearing socks and using protective bandages where you fear you may develop a callus or corn also helps. One of the key points of prevention is keeping toenails trimmed. When left to grow, long toenails can change the way we walk and cause us to place pressure on parts of the feet which are not used to it. This can cause other issues including plantar fasciitis, heel fat pad syndrome and a variety of knee and hip conditions.
Do I need to go to the GP or visit my local hospital?
A GP or local hospital visit should not be necessary for the management of corns and calluses. If you are experiencing extreme pain and difficulty walking, you should contact your local GP or hospital. The general management of corns and calluses can be approached via our foot health specialist who can return your feet to a healthy, comfortable and happy condition.
Springett, K., Whiting, M., & Marriott, C. (2003). Epidemiology of plantar forefoot corns and callus, and the influence of dominant side. The Foot, 13(1), 5-9. https://doi.10.1016/s0958-2592(02)00112-8
Grouios, G. (2004). Corns and calluses in athletes’ feet: a cause for concern. The Foot, 14(4), 175-184. https://doi.10.1016/j.foot.2004.07.005