People who suffer from different musculoskeletal pain can obtain relief from the use of orthopedic devices. The foot is most often the greatest area of pain. Devices for corns, flatfoot, a painful Achilles tendon and other conditions are described.
You can help many patients who have musculoskeletal pain – especially in the feet – by prescribing basic supportive and corrective devices. Complex problems usually require the services of a specialist.
Foot conditions that benefit from orthoses
Orthoses have many functions beyond providing support. Primary care physicians can make use of orthoses for various problems of pain and foot-ankle dysfunction. For many common foot ailments, a thorough history and physical examination of the bare feet are important starting points toward providing simple remedies, such as cushioning pressure points. Diabetics, who are especially vulnerable to foot problems, can benefit from cushioning that relieves pain and slows foot deterioration.
Orthoses – sometimes called orthotics – are devices that relieve pressure and pain, correct deformities, support body parts, or improve musculoskeletal functions. They are not the exclusive province of podiatrists, orthopedists, rehabilitation specialists, and orthotists. Some devices can be useful to primary care physicians in providing pain relief and restoring function. Orthoses should not be confused with prostheses, which are meant to replace hands, feet, limbs, or their parts.
Foot problems are among the most common reasons that patients seek medical attention. Patients are quick to view foot pain or dysfunction as impediments to everyday activities. Although specialists may be available, patients often bring foot problems to primary care physicians. Many such problems can be capably handled by physicians with an interest in lower-limb musculoskeletal defects, damage stemming from improper footwear, and illness or trauma affecting the feet.
Persons with flat feet do not necessarily experience discomfort. They may have lived with the condition for years and may require no treatment. If, however, flat feet cause symptoms or the patient is anxious about his or her feet, an examination is in order. The surest way to detect foot problems of any kind is to take a thorough history and examine the bare feet carefully. Foot specialists report that primary care patients are rarely asked to remove their shoes and socks for even a cursory physical examination.
Patients often neglect and abuse their feet by wearing unsuitable shoes that distort their feet, produce friction and pressure, or fail to provide adequate support. Some sustain injuries or develop conditions such as diabetes that threaten foot circulation and sensation. In addition, some have congenital deformities that complicate standing, balancing, and ambulation. Many of these patients seek simple remedies, and some may be unwilling to invest in expensive custom-made corrective footwear.
Patients with diabetes are especially vulnerable to foot problems, and surgery is frequently the therapy of last resort. Deformities, loss of sensation, and bone malalignments may cause tissue breakdown, ulcers, and infection, which may eventually lead to amputation. Cushioning with readily available materials may provide pain relief and may also slow deterioration of the foot.
Helping patients with foot problems
A small stock of padding and cushioning materials is useful for treating feet and modifying footwear in the office. A trial of foot orthoses may also indicate which permanent remedy is feasible. Some conditions that may be ameliorated include flatfoot, plantar fasciitis, corns and calluses, tight heel cords, limb length differences, inversion and eversion, and enlargement of the calcaneal tuberosity. Athletic shoes may be modified with orthotic devices as well.
Simple devices allow physicians and patients to manage some uncomplicated foot conditions. A stock of pads, cushioning material, bandages, tape, heel cups, arch supports, and the like may provide the basis of service to many patients, especially if they have only limited access to specialists. Such items can be purchased in modest quantities from medical or surgical supply companies at less cost than single items at drugstores. Preformed orthoses are also available from drugstores, supermarkets, and sporting goods stores. One such item is a foot-shaped pad that replaces the insole of a conventional shoe or a specially made, extra-depth (“deep”) shoe. The pad is supplied in different shapes to support or cushion foot structures. Because the pad must be thin, relatively little correction can be applied.
Many different kinds of materials are useful in orthotic therapy: cloth, felt, leather, cork, rubber, plastic, steel, and aluminum, among others. Many of the familiar cushioning devices are made of foam rubber or foam plastic. Two popular materials for insoles are Plastazote, a closed-cell polyethylene foam prepared in several densities, and Spenco, neoprene injected with nitrogen bubbles and covered with multistretch nylon fabric. Lamb’s wool is also effective in cushioning sore parts. In orthotic laboratories, thermosetting plastics can be molded to certain shapes that hold even when exposed to heat, and thermoplastics can be heated for shaping or reshaping into various devices. Some thermoplastics can be molded directly to the body to simplify the construction of supports.
Functions of a foot orthosis
- Provides a maximal and even distribution of the weight-bearing stresses over the entire sole.
- Reduces stress and strain on foot, ankle, knee, hip, and spine by properly controlling the inversion and eversion of the subtalar joint and supination and pronation of the transverse tarsal joint, and by absorbing part of the ground reaction forces.
- Provides relief for sensitive and painful parts of the sole such as atrophic, scarred, callused, and ulcerated areas.
- Supports the longitudinal and transverse arches of the foot.
- Relieves metatarsalgia of various causes (such as subluxation and dislocations of metatarso-phalangeal joints, Morton’s neuroma, fractures of metatarsals, sesamoiditis, and pes cavus).
- Controls the foot by decreasing the amount, degree, and rate of foot pronation during walking and running.
- Helps correct abnormal foot position.
- Provides accommodation for the foot that has missing parts because of congenital anomalies or amputation.
- Serves as an addition to an ankle-foot orthosis.
- Equalizes leg lengths by “raising the ground” to one foot.
- Limits the motions and weight-bearing stresses of various symptomatic foot joints.
- Minimizes the pressure and irritation from external (shoe) or internal (bony prominence) sources.
In addition to making simple corrections, another reason for using basic orthotic materials is to determine whether a more permanent remedy of the same kind is feasible. Armed with knowledge of the trial, a specialist can then devise more sophisticated, custom-made foot orthoses to provide long-term improvement in function. Cushioning or taping a painful joint may not only give relief but also point the way to a long-term solution.
In some cases, a different style of shoe may serve as an orthotic device. Women’s high heeled dress shoes that put considerable pressure on the forefeet or men’s fashionable shoes that are stiff, narrow, and pointed may be replaced by roomier models with lower heels and softer materials, as long as the patient is willing. Individuals with large bunions or calluses may obtain relief by wearing conventional shoes with holes cut into the uppers over tender skin areas. Stretching of uppers or specific spots on uppers by shoe repair shops is another approach to reducing pressure on bones and surrounding tissues.
The following conditions are among those that can be ameliorated by applying orthoses to foot or shoe or by substituting another style of shoe:
* Flatfoot (pes planus) Some patients with flat feet may never experience pain or discomfort. But in those who complain of aching arches, the problem may result from tension and fatigue in the muscles and plantar fascia. One simple remedy is to cut a piece of foam padding into a scaphoid form (like the boat-shaped carpal bone). Use the padding’s own adhesive or contact cement to attach it to the insole of the shoe along the long axis where the arch will rest on it. Similarly, shoemakers and orthotists sometimes attach a metatarsal bar transversely on the bottom of the sole to take pressure off the heads of the metatarsal bones if pain over the metatarsophalangeal joints is a problem.
* Plantar fasciitis This painful ailment may have several manifestations, such as irritation of the fascia, calcaneal spur, or heel bursitis. It is characterized by pain along the arch or on the plantar surface of the heel. Padding or cushioning of the arch – some sort of arch support similar to a scaphoid pad – may help relax the fascia. Alternatively, a gel-filled heel pad may be beneficial. Nonrigid supports are best.
* Corns and calluses These conditions are generally aggravated by the pressure of tight, narrow, pointed shoes. Often the pain can be assuaged by urging the patient to wear roomier, softer, or laced shoes: Athletic shoes may be suitable for many. A shoemaker’s swan, which resembles a very large pair of pliers with a peg on one side of the jaw and a ring on the other, can be used to stretch a shoe’s uppers at sites where pressure causes pain. Certain patients with severe pain may even be willing to cut holes or slits in their shoes to prevent friction on sore areas of skin. Pads of various kinds, however, are readily available and can be applied by patient or physician. Doughnut-shaped pads often give relief to corns on the interphalangeal joints of toes. Corns and calluses may have to be reduced by paring or application of acid preparations, perhaps by specialists.
* Tight heel cords (painful Achilles tendon) Taking the weight off a shortened tendon – lifting the heel – may suffice to eliminate pain. A heel cup made of rigid plastic, pliable plastic, or an even softer plastic can be inserted into a shoe to provide a 1/4-3/8-inch lift. A higher heel, especially in women’s shoes, may also diminish the effects of a short Achilles tendon. In some cases, a more sophisticated orthotic device or specially designed shoes may be necessary – or possibly surgery to correct tendon length or contracture.
* Limb length difference A disparity in the length of the lower extremities, with accompanying hip pain, may not require special shoes costing hundreds of dollars. Heel cups or pads may suffice for a small difference – 1/2-inch or less – in leg length, if the condition is uncomplicated. Observe the patient’s gait and examine the legs when extended straight out, at rest, on an examining table. Problems that may have been caused by polio or epiphyseal damage are often revealed.
* Inversion and eversion In these conditions, pes varus and pes valgus, respectively, orthotic therapy involves inserting compensating wedges between the heel and sole so as to turn the foot in the direction opposite to the one in which it tends. Or the heel or sole may be flared, that is, constructed more broadly to help prevent unnatural rotation of the foot. This work, however, requires the services of a pedorthist (or at least a shoemaker). Pes varus and pes valgus are not usually modified by placing orthoses inside the shoe.
* Enlarged posterosuperior calcaneal tuberosity Such a bony prominence, or “pump bump,” on the calcaneus at the insertion of the Achilles tendon appears mainly in women who wear high-heeled shoes. Symptomatic relief involves fastening a U-shaped pad to the inside rear of a roomy shoe, cutting down and padding the rear portion (counter) of such a shoe, or simply wearing sandals or open-back formal shoes.
Athletic shoes may also have to be modified for the benefit of runners and participants in other sports. Some of the same principles apply, even though the pressures on foot surfaces and structures are much greater than in street shoes with ordinary walking. Thus, custom-made shoes or orthoses are usually necessary. Flaring of soles on the medial margin of athletic shoes, for example, counters excessive pronation, a motion that includes elements of eversion, abduction, and flattening of the longitudinal arch. Semirigid inserts that transfer stress from one area of the foot to another are designed to provide symptomatic relief. Steel plates or springs are sometimes used under insoles to minimize movement around painful foot joints.
When to refer patients for therapy
Podiatrists are trained and certified in foot care and surgery, and certain orthopedists specialize in foot problems. Orthotists and pedorthists are technicians who design and build individualized orthoses. Detailed information from the history and physical examination is valuable to all specialists who must provide sophisticated services. Primary care physicians are in a good position to judge potential patient complaince and encourage use of orthotic devices.
A number of specialists provide services to patients who need further diagnosis and therapy for foot problems. Many physicians routinely refer patients to podiatrists, especially if these foot specialists are located nearby. According to surveys, more than half of all Americans with foot problems seek care from podiatrists.
Podiatrists, trained for at least four years in the specialty of foot care and foot surgery, are found in many settings. They often obtain referrals from physicians, collaborate with them on care, and enjoy privileges on hospital staffs. Podiatrists are licensed in all states and may be certified by any of several boards in their field.
Certain orthopedists take an interest in the foot, and local inquiries will determine who they are and whether foot and ankle clinics are available in the vicinity. Orthopedists with a special interest in the distal lower extremity have organized as the American Orthopaedic Foot and Ankle Society. Other physicians who may possess skills in orthotic applications include sports medicine specialists and physical medicine and rehabilitation specialists, especially those associated with university medical centers and rehabilitation clinics.
Chiropractors have shown increasing interest in diagnosing and treating foot problems. But many physicians hesitate to refer patients needing such services because chiropractors often lack specific training.
Technicians who prepare orthoses for patients are known as orthotists (or pedorthists if they specialize in foot devices). They prepare in-shoe orthoses and external appliances such as an ankle-foot orthosis (AFO). A familiar example of an AFO is the metal leg brace reaching to the knee and anchored by a stirrup attached to the shoe heel. For most conditions, metal devices have been succeeded by molded plastic orthoses, which are more comfortable and more acceptable to patients. Foot drop, which originates from neurologic damage and muscle paralysis, is an example of a condition that can be helped only by an AFO.
Specialists in foot management emphasize the importance of a good history accompanying each referred patient – information that might obviate detailed history taking and testing by a specialist and reduce the cost of consultation. The history should include
- Basic statistics, especially height, weight, shoe size, and other measurements
- The nature, location, and frequency of reported pain
- Previous treatment, such as taping, insertion of orthotic devices, or prescription of nonsteroidal anti-inflammatory drugs
- The favorable or unfavorable results of these therapies.
The symptom history should be fairly detailed. For example, it is not enough to know that cramping pain arises in the calf. If pain occurs when the patient stands up or stands for long periods, orthoses may be helpful. If, however, pain occurs suddenly during the night, ischemic vascular disease may be the problem, and mechanical treatment would be of no value.
Compliance is a serious consideration in referral for orthoses. Specialists point out that it makes little sense for patients to incur hundreds or thousands of dollars in charges if they fail to wear prescribed devices. Some patients find external orthotic devices cumbersome or embarrassing and revert to sandals, athletic shoes, or bedroom slippers that provide no benefit beyond a degree of comfort. Patients sometimes choose to be inactive rather than use their orthotic devices. The primary care practitioner is usually in a good position to judge whether a patient is willing to cooperate in therapy.
Another important role for the primary care physician is to encourage the patient with an orthotic device to take whatever instruction in its use may be available and to use the device regularly. If the orthosis fails to operate properly or needs adjustment or repair, the patient should be urged to seek expert help.