A corn is simply an area of hard, thickened skin that can occur on the top, between, or on the tip of the toes. A callus is similar in nature, but is larger and usually occurs across the ball of the foot, on the heel, or on the outer side of the great toe. Corns and calluses are often mistakenly considered a "skin" condition. They are actually the visible sign of an underlying "bone" problem.
Everyone knows that "big oaks from little acorns grow", but few realize that "big aches from little toe corns grow". Calluses and corns quite often have painful nerves and bursal sacs (fluid-filled balloons that act as shock absorbers) beneath them, causing symptoms ranging from sharp, shooting pain to dull, aching soreness.
First, your doctor will conduct a thorough inspection of these areas. He/she may gently trim some of the thickened skin away, in order to rule out a wart (caused by a viral infection of the skin) as the culprit. X-rays will often be taken to identify the specific bone problem that is causing the corn or callus. The doctor may place a small marker on the corn before taking the x-ray, to make it's location visible on the x-ray. The finished x-ray will then show the location of the corn and the bone spur underneath that caused it.
Corns and calluses form due to repeated friction and pressure, as the shoe (or ground) rubs against a bony prominence (bone spur) on the toe or foot. The skin thickens in response to this pressure, in order to keep you from getting an open sore or blister. Small amounts of friction or pressure over long periods of time cause a corn or callus. Large amounts of friction or pressure over shorter periods of time cause blisters or open sores. Corns can be due to a buckled or contracted toe position called a hammer toe. Often toes curl under the neighboring toe (especially the smallest toe) causing corns to form. Calluses develop under a metatarsal head (the long bone that forms the ball of the foot) that is carrying more than its fair share of the body weight, usually due to it being dropped down or due to its longer length. (Figure 2) Many of these bone conditions are inherited. A poor choice of shoes can aggravate corns and calluses, but often it is not the "sole" cause. (No pun intended.)
At Home Treatment
Trimming of this thick skin can relieve the pressure for a short time. You should never consider doing this yourself if you are diabetic or have poor circulation. If you cut yourself, you may cause an infection. Corn pads and callus removers often have harsh acids that peel this excess skin away after repeated application, but they can cause a severe chemical burn, which might lead to infection and greater pain than the original foot condition....so be careful with self-care. You can begin by soaking your feet in warm soapy water and gently rubbing away any dead skin that loosens. A pumice stone, buff bar or emery board is then use to "file" this thickened skin. This should be done gradually, a bit a a time, ideally after each shower or bath.
Attempting to file off the entire thickness of a corn or callus can result in a burn or abrasion. Applying a good moisturizer such as Vitamin E oil, cocoa butter, or lanolin to the hardened areas should keep them softer and relieve pain. Non-medicated corn pads or moleskin (a thin fuzzy sheet of fabric with an adhesive back) can be purchased to protect corns and calluses, but should be removed carefully, so you do not tear the skin, and should only be worn for a day at a time.
After an initial history and physical exam of your feet, x-rays will be needed to tell the whole story and determine why corns and calluses are developing. Your doctor is the expert in trimming down these areas of thick skin and will often apply comfortable padding to these painful corns and calluses. Special padding devices and materials may be available only from your doctor for your use at home. Medication for inflammation may be utilized to treat the underlying injury and sometimes a cortisone injection into the underlying bursal sac will be recommended to rapidly reduce pain and swelling.
Changes in shoewear may be recommended. A prescription custom-made device called an orthotic might be made to wear inside your shoes, to redistribute pressure more evenly across the ball of your foot. A pad placed in your shoes (called a metatarsal pad) may help reduce your contracted hammer toes and relieve pressure on the ball of the foot as well. Often corns and calluses will have to be trimmed on a regular basis to prevent them from hurting. Eventually, you may desire corrective foot surgery by your podiatrist to straighten curled or contracted toes for corns or elevate and shorten metatarsals for calluses. Often such surgery represents a short term inconvenience to your lifestyle, but will not require any lengthy period of rest or inactivity. Many satisfied patients have remarked that surgery to remove the bone beneath the corn hurts less the very next day than on a painful day walking in their shoes with the corn present.
Often changing your style or size of shoes may help. Carefully review the shoes in your closet. Check their fit and discard any that have seams and stitching over painful corns or have worn out innersoles that offer too little protection for calluses on the ball and heel of your foot.
Make sure shoes are wide enough for your feet and have enough depth in the toe area to allow minimal pressure on the toes. To demonstrate whether your shoes are of adequate size and shape, place your foot on a blank sheet of paper and trace the shape of your foot. Then, place the shoe in question on top of your foot tracing. You may be surprised, as are many people, that your shoes are actually smaller and narrower than your feet. Try to imagine the forces present in that shoe when you squeeze your foot into it and then walk at any speed. Ouch !
Review the socks in your drawer. If they have thick seams at the toes or holes, it's time to go shopping. Try to choose natural materials such as cotton and wool. Several types of socks (such as Thor-lo brand) have a double thickness in the toes and heels to protect these areas. Nylon hose can be purchased that have a woven cotton sole on the bottom of the foot to offer less friction and more padding.
Corns and calluses almost always persist until corrective surgical measures are taken, so don't become discouraged if your efforts to prevent them are less than successful.