How often have you been offered a chair and invited, colloquially speaking, to “take the weight off your feet?” However inelegantly put, the invitation is usually welcome, for the feet bear a tremendous burden in the course of day-to-day living. Considering that an average day of walking subjects the feet to a force equal to several hundred tons, it is little wonder that they ache by nightfall.
Like other parts of the body, the feet are highly specialized structures. Each is made up of 26 bones, laced with ligaments, muscles, nerves and blood vessels. The principal functions of the feet are weight-bearing and locomotion. Their range of motion allows them to move with ease over practically any surface, whether it is rough, uneven or slippery. Their flexibility enables the ballet dancer to stand on one toe, the climber to gain a foothold on a rock face, the circus performer to walk the tight wire, or the small child to gain a few inches to reach the forbidden cookie jar.
But as versatile as they are, our feet are also prey to countless problems. Because of their location and the fact that they must support all our weight, the feet are subject to more pressure and injury than any other part of the body. They can also be affected by congenital or hereditary malformations, such as clubfoot. (Such problems can usually be corrected in infancy with special casts or braces.)
Other foot problems may be an indication of some other underlying health disorder. Circulatory problems, diabetes, anemia and even kidney disorders are often first detected in the feet. Foot joints are frequently the first to be involved when arthritis strikes.
Still other foot problems are brought on by personal habits, sometimes the result of following fashion rather than common sense in choosing shoes. Among the more common foot ailments are corns and calluses, warts, athlete’s foot, ingrown nails, and bunions.
Corns and calluses are very much alike. Both have a marked thickening of the top layer of the skin, caused by long periods of pressure or friction against the skin. Calluses can develop anywhere on the weight-bearing areas, such as the sides and soles of the feet. They are usually raised, off-white in color, and have a normal pattern of skin ridges on the surface.
Corns come in two major varieties – hard and soft. Hard corns are the more common, usually occuring on the surfaces of the toes. They appear shiny and polished. Soft corns are whitish in color and are most often found on the web between the fourth and the little toe. Unlike calluses, corns have a central core, which consists of a base on the surface of the skin and an apex pointing inward. Pressure of the core on nerve endings in the skin causes the pain of corns.
Calluses and corns usually develop from wearing ill-fitting shoes, socks or stockings. They may also occur as a result of an underlying foot problem such as a bony growth on the toe.
Calluses and hard corns can be self-treated with over-the-counter (OTC) drug products, according to a panel of experts that assisted FDA in its review of ingredients in these products.
Salicylic acid is the only ingredient the panel found safe and effective for treating calluses and hard corns. The experts recommended it be used in concentrations of 12 to 40 percent in pads, plasters and disks and at concentrations of 12 to 17.6 percent in collodion (a solution of nitrocellulose), which leaves a transparent film when applied to the skin. The panel said there was insufficient data on which to recommend a concentration of salicylic acid that would be safe and effective for treating soft corns. They called for studies on soft corn treatment. (FDA’s proposed rules on OTC drug ingredients for callus and corn treatment have not yet been published.)
Other types of treatment include removing some of the thickened skin – something that should be done only by a doctor – and using pads to relieve pressure over bony growths. Occasionally these growths are removed surgically.
Warts on the bottom of the feet, called plantar warts, are often mistaken for calluses, but they have nothing in common. Although the pressure of walking on plantar warts can cause pain, pressure does not cause them. Plantar warts, like warts on other parts of the body, are caused by a virus.
A plantar wart can grow only on the bottom of the foot and occurs in children as well as adults. It may appear singly or in clusters. The wart is flat and may be either hard or soft. Because they are caused by a virus, warts can be spread from one person to another either directly or indirectly in public area such as swimming pools or showers. For this reason, many medical experts feel warts should be removed even though most of them will go away by themselves in time.
Salicylic acid is the only safe and effective OTC ingredient the panel found for removal of warts. This ingredient acts as a skin peeler, destroying the wart tissue. Because the drug can harm healthy skin, the panel recommended keeping the product away from surrounding skin, preferably by encircling the wart with a ring of petroleum.
If there is any doubt about a wart, a doctor should be consulted. Wart treatments that doctors use include freezing the wart with liquid nitrogen, removing it surgically, or using prescription drugs. Single-dose X-ray treatment is another otpion but is less common today than it once was.
Athlete’s foot is a fungal infection that, despite its name, is not exclusive to the locker room. It usually occurs in men between the ages of 14 and 40, but women also may fall prey to the fungus.
Itching, burning and redness are the common symptoms of athlete’s foot (known medically as tinea pedis). White scale (flaking skin) develops in the toe-web, especially between the fourth and little toe. Blisters may also occur. On the sole of the foot, athlete’s foot may appear as irregularly grouped blisters and superficial scale.
The fungi that most commonly cause athlete’s foot – Trichophyton mentagrophytes, T. rubrum and Epidermophyton floccosum – are prevalent in homes, offices and athletic facilities, but that doesn’t mean everyone passing through will get the affliction. However, the chance of infection increases if there is broken skin or increased moisture from tight shoes, excessive sweating, humid summer weather, or a tropical climate.
To treat athlete’s foot, FDA’s expert advisory panel on OTC antimicrobial drugs recommended using OTC drugs that contain iodochlorhydroxyquin, tolnaftate, or undecylenic acid and its calcium, copper and zinc salts. Tolnaftate can also be used to prevent, as well as treat, this condition, the panel said.
The panel also recommended that haloprogin and miconazole nitrate be switched from prescription to OTC status for the treatment of athlete’s foot. Nystatin, another prescription drug recommended for OTC use, should be used only in combination with other safe and effective OTC ingredients, the panel said. (Proposed rules covering these ingredients have not yet been published by FDA.)
An ingrown toenail almost always afflicts the big toe and occurs when a section of the nail curves into the flesh of the toe corners and becomes imbedded in the soft tissues, causing pain, swelling, inflammation and ulceration.
Incorrect trimming of the nails is usually the cause of ingrown toenails, although pointed-toe shoes and tight shoes and hosiery may also be to blame. People with nails that curl naturally are more likely to develop this condition.
To avoid ingrown toenails, the nails should be cut straight across without tapering the corners.
Unfortunately, FDA’s expert advisory panel did not recommend any OTC ingredients as being safe and effective for self-treatment of the discomfort of ingrown nails. Medical treatment is aimed at relieving external pressure and includes prescription medications that will harden the nail groove or help shrink the soft tissue. Hot packs may be applied, as well as topical antiseptics and medications to control infection. In stubborn cases, surgery may be needed to remove part of the nail.
Few foot afflictions are more disfiguring and painful than bunions. Many experts blame ill-fitting shoes for this condition, while others consider this an over-simplification. Bunions have been known to occur in people who don’t wear shoes and, conversely, don’t always develop in people whose footwear is poorly fitted. Heredity, flat feet, and structural defects resulting from poliomyelitis or cerebral palsy also make some people more prone to bunions.
Bunions are actually misaligned big toe joints that become swollen and tender. The technical name is hallux valgus – hallux being the Latin name for the great toe and valgus another Latin word meaning bent outward. Normally the bones of the big toe lie more or less in a straight line with the large metatarsal bone of the foot. When a bunion develops, the large metatarsal bone angles outward, away from the other metatarsals, and the big toe bones are forced in the opposite direction (see illustration). Pressure over this joint causes inflammatory swelling of the bursa, a fluid-filled sac that prevents friction between two bones of a joint.
Bunions may not produce symptoms, but usually they become quite painful, swollen and tender. The skin over the bunion may become thick and rough. There are no topical medications that will make a bunion go away. Use of protective pads and shoes that do not constrict the front part of the foot may help in relieving symptoms. Often the only answer to this deformity is surgery, which ranges from removal of bony outgrowths on the toe to joint resection (cutting away parts of the bone itself), fusion, and toe realignment.
Corns, calluses, warts, athlete’s foot, ingrown toenails and sometimes even bunions can, to a large extent, be prevented by proper foot care. This includes selection shoes that fit correctly, keeping the feet clean and dry, and trimming nails properly.
Good foot care is particularly important in helping the elderly to live useful, satisfying lives. Foot ailments make it difficult for many older people to work or participate in social activities.
To keep older people mobile, the American Podiatric Medical Association (the professional organization of foot doctors) recommends walking as the best exercise for the feet. Shoes with a firm sole and soft upper are best for daily activities, the association says. Socks or stockings should be of the correct size and preferably seamless. Elderly people should not wear constricting garters. Feet should be bathed and inspected daily.
For diabetics of any age, these foot-care recommendations are not only important – they are extremities can have serious consequences. Because diabetics tend to have poor circulation, they must avoid anything that will decrease blood flow to the feet, such as wearing tight shoes, constricting socks or garters, or even sitting cross-legged.
Diabetics are more prone of infection; thus any break in the skin is a danger sign. Because they often lose sensation in their feet, diabetics may cut themselves or develop an infection without knowing it. For this reason, it is important that the feet be bathed daily and inspected for cuts, swelling or sores. Bath water should be warm, never hot. And diabetics should never use hot water bottles or electric blankets on their feet.
Commercial corn, callus and wart removers, which are caustic, are not for the diabetic, either. They can destroy tissue and pave the way for infections. Labels on such preparations usually warn against use by diabetics. Finally, diabetics should have a podiatrist remove corns, calluses and warts and trim toenails, rather than doing this themselves. This not only provides an opportunity for a careful foot examination by a doctor but avoids the chance of infection from accidental cuts.