What causes them?

You just got home from your evening walk and are taking off your shoes and socks. On your left foot, you notice that there’s a hard, raised bump on your heel. You press on the area, but it doesn’t hurt. You ask your doctor about it at your routine visit the following week. After looking at it, she says, you have a callus. What caused it to occur? Can it be removed? What do you need to do to prevent more calluses from forming?

Definition

Calluses are thick, hardened layers of skin. They develop when your skin protects itself against friction and pressure from repetitive action. Typically, they appear on the feet and toes or hands and fingers. They can vary in size and shape. Corns are smaller than calluses. They have a hard center that’s surrounded by inflamed skin. Usually, corns hurt when pressed (calluses are rarely painful). The most common symptoms are a thick/rough area of skin, hardened/raised bump, tenderness/pain under your skin, and flaky/dry/waxy skin.

There are three leading causes of calluses. The first is wearing improperly fitting shoes. If your shoes are too tight or you frequently wear high heels, parts of your feet can be compressed. If your footwear is too loose, your feet may repeatedly slide and rub against the inside of the shoe. The second trigger of calluses is not wearing socks because it can result in your feet rubbing directly on your shoes. Also, if your socks don’t fit properly, it can be a problem. The third source of calluses is playing instruments or using hand tools without gloves. Calluses on your hands result from the repeated pressure placed on them by doing a repetitive task, including something as simple as writing. Some things increase your chances of developing calluses, such as bunions, hammertoe, or bone spur. A bunion is an abnormal, bony bump that forms on the joint at the base of your big toe. A hammertoe is a deformity in which your toe curls like a claw. A bone spur is a bony projection that develops along bone edges, usually where bones meet (joints).

Treatment

The first part of the treatment process for calluses is to avoid doing the repetitive actions that caused them. Next, you can use over-the-counter pads to protect the area. There are nonprescription liquid corn removers that you can try. Be careful with this since they contain salicylic acid, which can irritate healthy skin. To remove the thickened skin, soak the area in warm, soapy water to soften the skin before using a pumice stone, nail file, emery board, or washcloth to help remove a layer of toughened skin. Don’t use a sharp object to trim the skin because it could lead to an infection. Afterward, apply moisturizer to help keep the skin soft. Until your callus is gone, wear well-fitting, cushioned shoes and socks.

If none of these measures work or you have diabetes or another condition that causes poor blood flow, you should see your doctor. They can trim thickened skin with a scalpel. They may also apply a patch containing 40% salicylic acid and will let you know how often you need to replace it. Similar to the self-care treatment, they’ll likely want you to use a pumice stone, nail file, or emery board to smooth away dead skin before applying a new patch. If you have an underlying foot deformity, you may need custom-made padded shoe inserts (orthotics) to prevent recurring corns or calluses. If your calluses result from bunions, hammertoe, or bone spur, your doctor may recommend surgery to fix them.

Prevention

To prevent calluses (and corns), the steps are simple. It’s vital to wear shoes that give your toes plenty of room. A good way to tell is if you can wiggle your toes. If you can’t, your shoes are too tight. You can have a shoe shop stretch your shoes for the spots that rub or pinch. You can also use protective coverings, like felt pads, nonmedicated corn pads, or bandages. Place these over areas that rub against your footwear. If your toes rub together, try toe separators or lamb’s wool between your toes. Always wear socks to prevent your shoes from rubbing directly on your feet. When working with hand tools, wear padded gloves. Another option is to pad your tool handles with cloth tape or covers.

While calluses aren’t necessarily sightly, they don’t usually cause any problems. The good news is they can easily be resolved. If you have any questions or concerns about calluses, please speak with your doctor. If you would like more information, please visit the American Academy of Dermatology Association’s Corns and Calluses page at https://www.aad.org/public/everyday-care/injured-skin/burns/treat-corns-calluses