Corns

There are both intrinsic (internal) and extrinsic (external) factors that can contribute to the development of corns and calluses:

Extrinsic (External) Factors:

• Poorly fitted or open-toed footwear
• Shoes with irregularities such as poorly placed seams or stitching
• High-heeled shoes
• Wearing shoes without socks
• Physical activities that create excessive pressure and friction, like running, jogging, or climbing
• Professions that subject the skin to constant friction or pressure, such as those of athletes or construction workers

Intrinsic (Internal) Factors:

• Bony prominences in the feet
• Malunion fractures
• Abnormal foot mechanics
• Cavovarus foot (a condition where the foot has a higher-than-normal arch and the heel turns inward)
• Toe deformities such as claw toes, hammer toes, or mallet toes
• Short first metatarsal (the shortest metatarsal bone at the base of the big toe)
• Hallux rigidus (stiffness in the big toe)
• Transfer lesions from osteotomy or removal of an adjacent metatarsal head
• Being overweight

In most cases, doctors can identify corns and calluses through a visual examination. However, additional diagnostic methods may include:

Medical History and Physical Examination:

• The doctor will evaluate the patient's footwear and inquire about any previous treatments, such as osteotomies or orthoses.
• Assessment of the patient's gait and foot alignment for any mechanical issues.
• Examination of the location and characteristics of keratotic lesions.
• Investigation of any structural issues with the bones of the feet and their alignment.

Imaging Tests:

The doctor may order specific tests to understand the cause of the corn formation:

• Dermoscopy: A non-invasive method primarily used to examine skin lesions and areas with excessive keratin buildup.
• Radiographs: X-rays of the weight-bearing feet may help identify any bony prominences contributing to corn formation.

Additional Tests:

Other diagnostic tests that may be performed include:

• Blood Tests: Tests such as fasting glucose levels and rheumatoid factor can help identify underlying conditions causing foot deformities.
• Pedobarographic Studies: Pressure measurements (pedobarographs) of the feet can highlight areas of excessive pressure linked to corn formation.

Here are some tips to help prevent the formation of corns and calluses:

• Choose well-fitted shoes: Shoes should not require breaking in or be excessively loose. They should be comfortable from the moment you wear them.
• Allow space for the toes: Ensure there is about half an inch of space between the shoe’s end and your longest toe. For athletic shoes, leave up to an inch of space.
• Check the shoe width: The shoe should provide enough room across the ball of the foot. The first metatarsophalangeal joint (where the big toe meets the foot) should align with the widest part of the shoe.
• Ensure a snug heel fit: The heel should fit comfortably, preventing any slipping or rubbing.
• Fit over the instep: For shoes with laces, this area can be adjusted to fit comfortably over the top of the foot.
• Avoid excessive friction or pressure: Stay away from activities that place constant friction on the skin.
• Wear appropriate socks and gloves: Ensure socks fit well and are free from irritating seams.

Specialists to Consult

While corns are not life-threatening, they can be uncomfortable and troublesome if left untreated. Several healthcare professionals can help with diagnosis and treatment:

• Podiatrist
• Dermatologist
• General Physician
• General Surgeon
• Orthopedic Specialist

When to See a Doctor?

If corns or calluses cause persistent pain or interfere with your daily activities, it's important to consult a podiatrist or foot specialist.

Note: Individuals with conditions such as diabetes, poor circulation, or other serious health issues should have their feet checked regularly to prevent complications. If you notice any signs of corns or calluses, seek medical advice.

Corns and calluses can interfere with daily activities, and treatment may be necessary to improve comfort and quality of life. The main goals of treatment are as follows:

• To provide relief from symptoms
• To identify and address the mechanical causes
• To develop a conservative treatment plan, including advice on footwear and orthotics
• To consider surgical intervention if conservative measures are ineffective

The following treatment options may be used for managing corns:

• Manual Removal: After soaking, you can use a nail file, emery board, or pumice stone to gently remove thickened skin from the affected area.
• Topical Keratolytic Agents: These products help soften and break down the corns. They typically contain salicylic acid (12.6-40%), applied as a pad or solution. Other ingredients such as urea (20-50%), silver nitrate, and hydrocolloid dressings may also be used.

Note: Newer hydrocolloid dressings have been studied for their ability to hydrate and soften keratotic lesions, though they should be used carefully to avoid skin burns from overuse.

Caution: Neuropathic and immunocompromised individuals should avoid using these agents.

• Gentle Paring (Debridement) or Enucleation: Sharp debridement can help reduce pain by removing excess keratotic tissue and reducing pressure on nerves in the underlying skin layers. This is usually done with a scalpel, and local anesthesia may be used if necessary. After soaking the affected area, the corn can be gently trimmed using a pumice stone to help prevent recurrence.

• Laser Therapy: Lasers like the erbium-doped yttrium aluminum garnet (Er:YAG) laser (2,940 nm) are used to treat corns with minimal thermal damage. The carbon dioxide laser has also proven effective. However, if the underlying causes remain unaddressed, lesions may recur.

• Cushioning and Foot Biomechanics/Orthotics: Altering the biomechanics of the foot and using cushioning can help both prevent and treat corns. Orthotic devices such as doughnut-shaped pads, heloma shields, and silicone toe splints help redistribute pressure and relieve stress on the central core of the corn.

• Silicone sleeves can also soften the corn by releasing mineral oil, while interdigital wedges made from foam padding or silicone splints can aid in the healing of soft corns between the toes.

• Surgery: For patients who do not respond to conservative treatments, surgery may be considered. In rare cases, surgery to correct structural foot problems, such as deformities in the bones, may be required to treat recurring corns that do not improve with padding, shoe inserts, and periodic trimming.

Note: Diabetic patients or those with poor circulation should not attempt to treat corns on their own, as this may lead to skin injury. Treatment should always be done under the care of a medical professional.

While corns may seem like a minor issue, they can lead to more serious problems if left untreated. Potential complications include:

• Pain
• Tinea pedis (a fungal infection commonly found between the toes)
• Ulceration and infection
• Septic arthritis
• Osteomyelitis (bone infection)

Post-surgical complications may also occur, such as:

• Swelling in the digits
• Numbness
• Infection
• Floppy or flail toes
• Recurrence of deformity
• Stiffness in joints and toes

While surgery is often considered the conventional method for treating persistent corns, it is not always a permanent solution. Since corns have a tendency to reappear, ongoing management and preventive measures are essential to minimize recurrence.

Before attempting to treat a corn, it is important to first identify the cause of the friction. In many cases, corns may resolve on their own once the pressure or irritation that caused them is removed. If taking steps to reduce further irritation doesn’t help, a podiatrist or GP may recommend the following home care strategies:

• Soak the Affected Area: Soak the corn or callus in warm water for 15-20 minutes to soften the skin, making it easier to treat.
• File or Pumice the Surface: Use a pumice stone to gently file the corn or callus after soaking. Soak the pumice stone in warm water before using it in gentle circular or side-to-side motions.
• Avoid Excessive Skin Removal: Be cautious when filing the skin. Over-filing can lead to bleeding and increase the risk of infection.
• Trim Toenails Regularly: Long toenails can press against shoes, contributing to the formation of corns. Keeping toenails trimmed helps to reduce this pressure.
• Use Padding: Place donut-shaped adhesive pads around the corn to prevent direct contact with shoes. For calluses, moleskin can be used to cushion the area and reduce irritation. You can also create a protective “donut” with materials like moleskin, lamb's wool, felt, or foam. Many pharmacies offer over-the-counter products for cushioning corns and calluses.
• Wear Properly Fitted Shoes: Tight shoes are a common cause of corns and calluses. Opt for low-heeled shoes that fit well, avoiding shoes that are too tight or too loose to minimize the irritation.
• Moisturize Regularly: Use lotions or creams containing salicylic acid, ammonium lactate, or urea. These ingredients help soften tough, hardened corns and calluses over time.

While corns and calluses are generally not serious, they can be bothersome and interfere with daily activities. Managing them promptly is key to minimizing discomfort and preventing further issues. Here are some practical tips for handling corns and calluses:

• Preventing Calluses on Hands: To avoid calluses on your hands, consider wearing gloves during activities such as gardening, weightlifting, or other tasks that involve repetitive friction.
• Preventing Calluses on Feet: Wearing properly fitting shoes and socks is the best way to prevent calluses on the feet.
• Preventing Corns on Feet: Shoes with a wider toe box can help prevent corns on the feet, as they reduce friction against the toes.
• Protection During Physical Work: For additional protection, use gloves when handling tools like a garden rake or spade.
• Wear Padding for Other Body Areas: If you’re engaging in activities that apply friction to other parts of your body, such as kneeling while laying carpet, use knee pads to protect your knees.

A podiatrist can help you make changes in your footwear or lifestyle to reduce or prevent the occurrence of corns and calluses.

For diabetic individuals, foot problems are more common, and taking proper care of the feet is especially important. Keeping blood glucose levels under control is essential in preventing complications related to diabetes, such as nerve damage (diabetic neuropathy), which can lead to a loss of feeling in the feet. This condition makes it difficult to detect minor injuries, like cuts or blisters, which can become infected if left untreated.

To help maintain healthy feet, follow these steps every day:

• Check your feet daily for any signs of damage.
• Wash your feet regularly with warm water.
• Gently smooth any corns or calluses.
• Trim toenails straight across to prevent pressure on the toes.
• Always wear shoes and socks.
• Protect your feet from extreme temperatures.
• Get your feet checked at every healthcare visit.