Inside Insights On Common Orthotic Dilemmas

Author(s): 
Ronald Valmassy, DPM

   When treating patients with orthotic therapy, podiatric physicians may face various dilemmas on when to prescribe devices or how to treat patients who have used over-the-counter devices to no avail. These expert panelists discuss the use of orthoses after bunion surgery, “retail” orthoses and the treatment of pediatric patients among other issues.

Q: When would you prescribe functional foot orthoses following bunion surgery?

   A: For most hallux valgus patients, David Levine, DPM, CPed, would recommend orthotic devices. “Even more important than orthotic devices is educating the patient about footwear and what to look for,” he advises. “Once (patients are) in the appropriate footwear, then the function and performance of orthotic devices will make a lot more sense as well as increase the chances of patient adherence.”

   Michael Burns, DPM, considers hallux valgus deformity a symptom of midstance midfoot instability and functional hallux limitus. He always suggests orthotic control following hallux valgus repair unless the midstance instability has improved following a Lapidus fusion or some other ancillary procedure. In practice, he encourages patients with first metatarsophalangeal joint (MPJ) pain to try orthotic control before surgery (unless there is secondary involvement of the second MPJ). Dr. Burns maintains that the symptoms often resolve without surgery.

    “This allows the patient a reasonable option regarding treatment for the deformity and its timing,” says Dr. Burns.

   Since bunion deformities are precipitated, perpetuated, aggravated by or accentuate pathomechanical foot and limb function, Joseph D’Amico, DPM, routinely prescribes foot orthoses prior to surgical intervention. As he notes, correction of the hallux valgus does not correct the underlying forces that have created the hallux valgus nor will it prevent those forces from recurring postoperatively.

   Dr. D’Amico incorporates the orthotic device in the postoperative dressing either as an additional layer secured by elastic compression or by placing the orthotic in the postoperative shoe and securing it with Velcro if necessary. He notes that an established patient will already be accustomed to wearing these devices.

   In contrast, new patients who are anxious to have their deformity repaired should wear the new orthotics long enough to become comfortable and secure in their use prior to surgery. Dr. D’Amico says immediate use of an orthotic postoperatively reduces pathomechanical forces through the operative site, which reduces the likelihood of abnormal stress, improves stability and reduces discomfort.

   If he anticipates significant changes in sagittal or frontal plane alignment of the first MPJ, Dr. D’Amico will adjust the orthotic appropriately. His typical modifications may include first ray cutouts or forefoot post adjustments.

Q: Your patient has just spent several hundred dollars for an “orthotic” he or she has obtained from a retail outlet. When asked your opinion on this, how do you respond?

   A: “What you have purchased is not truly an orthotic device but a custom made insole,” Dr. D’Amico tells patients. “The person or automated machine that fabricated this device is not a physician of the foot and leg, is not trained in lower extremity biomechanics, and has not performed a history and comprehensive physical examination. If it has been suggested that this individual is qualified to assess and treat your condition, he or she is actually practicing medicine without a license.”

   While these patients may find these devices comfortable and helpful, Dr. D’Amico says it is unlikely that the underlying cause of the patient’s concern has been identified or properly addressed. He also tells patients these devices may actually be causing more harm than good.

   In most cases, he notes such OTC devices were made from a weightbearing foam impression of the patient’s feet. The foam impression allows the foot to deform and spread during the casting process. Accordingly, Dr. D’Amico says it is impossible to reposition or realign the plantar aspect of the foot from this position. In addition, he says with that casting method, one cannot visualize the plantar surface.

   The result is a model of the foot as it is but not as it should be, notes Dr. D’Amico. He tells patients they feel comfortable because the orthotic is distributing the pathological forces over the entire foot rather than one painful segment. Dr. D’Amico says this is similar to buying larger pants to feel more comfortable after gaining weight, which does not address the underlying problem.

   In the same vein, Dr. Levine notes the bottom line is to explain that an arch support is just that and nothing more. A pair of custom devices is more than a step up from OTC devices, he says. Just as prescriptions for glasses differ for each eye, he reminds patients that no two feet are alike, even on one person. Custom devices take even the subtle differences in feet into account whereas the OTC devices are just a pair of the same device, notes Dr. Levine. If the OTC devices do not adequately address the problem or the pathology, he feels it is time to step up to custom devices.

   If the OTC orthoses have a good fit with the shape of the foot and adequately control midstance instability, Dr. Burns tries to work with them. If they do not meet these requirements, he tries to explain the differences to the patient. Dr. Burns notes that sometimes patients have several different pairs and one may be adequate.

   Dr. Burns acknowledges a conundrum when patients have tried several varieties of orthotic control and still have symptoms that may be amenable to orthotic therapy. “Should I assume that their symptoms will not respond to orthotic control and propose another treatment strategy (often surgical), or should I try to convince them to try yet another orthotic device?” he asks.

   Dr. Burns notes the same issue arises when he considers OTC supports. He approaches this issue by sharing his thoughts with the patient and encouraging the patient to let him make another attempt at orthotic control before moving on to more aggressive treatment plans.

   In 25 years of experience with computer assisted gait analysis, Dr. D’Amico has found most of these faux “orthotics” increase the weightbearing surface, increase shock absorption, decrease stability and do not improve objective gait parameters. He adds that these devices may produce asymmetrical pathologic alterations in weight distribution patterns through the ankle, knee, hip and spine.

Q: What is the earliest age you would prescribe functional foot orthoses for a child? What conditions would you most typically be treating?

   A: Dr. Levine does not determine orthosis use by age but by symptoms and/or pathology. He advises starting out with OTC devices and tracking progress. If this is not sufficient, then custom devices are necessary, according to Dr. Levine.

   Dr. Burns uses an OTC support until the child is about 5 years old. He feels that when youngsters can walk down the stairs one step at a time without holding on to the handrail, they have developed a propulsive phase. Dr. Burns notes this may be a useful milestone to determine when functional orthotic control may be adequate. More often than not, he uses some type of deep heel cup and high medial flange along with a functional device for children. Dr. Burns notes this combination seems to help keep them “on top” of the device.

   When it comes to children, Dr. D’Amico most commonly treats excessive pronation, which may be the result of a variety of conditions but probably the most common would be developmental flatfoot. He starts treatment as soon as the child is able to achieve unassisted stance at 7 to 9 months of age. At this time, the immature and malaligned osseous infant foot framework begins to be susceptible to the deforming effects of gravity, according to Dr. D’Amico.

   Dr. D’Amico subscribes to a basic orthopedic tenet for the correction of pediatric musculoskeletal deficiencies: the earlier one institutes treatment, the more favorable the prognosis. He says early intervention in the developmentally challenged foot leads to bony remodeling to more normal alignment or structure, according to Davis’ law of soft tissue and Wolff’s law of bone.1
Q: Have you ever discontinued orthotic treatment in a pediatric patient or are these patients “patients for life”?

   A: Before he stops orthotic therapy, Dr. D’Amico says children must meet the following criteria:

   • absence of visible pronation;
   • absence of symptomatology;
   • realignment of lower extremity osseous and soft tissue structures;
   • normal lower extremity function (i.e. first ray stability, active propulsion);
   • normal center of gravity and center of vertical force pathways;
   • normal postural complex including upper extremity skeletal alignment; and/or
   • complete skeletal growth.

   Dr. Burns cautions parents that a pronated foot may need lifelong treatment. He tells parents it is their responsibility to allow adequate control while the child is growing. Then they can decide for themselves about symptomatic treatment after bone growth is complete.

   In Dr. Burns’ experience, 10 to 15 percent of children with excessive pronation develop fairly normal foot function without midstance instability before bone growth is complete and he discontinues orthotics for those youngsters. He usually sees those patients a couple of times over the next several months to confirm that their feet remain stable.

    “It is difficult to say whether they might have developed ‘normal function’ without orthotic treatment,” notes Dr. Burns.

   Dr. Levine sometimes discontinues orthotic therapy in this patient population but not always intentionally. As he explains, if patients outgrow devices, they may be lost to follow-up. However, Dr. Levine says symptoms also may resolve, particularly if patients have growth-related issues. He adds that monitoring and follow-up can help the decision process.

Dr. Burns is the CEO of Burns Lab. He is a Fellow of the American Academy of Podiatric Sports Medicine and a Fellow of the American College of Foot and Ankle Surgeons. Dr. Burns is a Diplomate of the American Board of Podiatric Surgery.

Dr. D’Amico is a Fellow of the American Academy of Podiatric Sports Medicine. He is in private practice in New York City.

Dr. Levine is in private practice and is the the director and owner of Physician’s Footwear, an accredited pedorthic facility, and Walkright, a shoe store, in Frederick, Md. He is a Fellow of the American Academy of Podiatric Sports Medicine and a member of the American Society of Podiatric Surgeons.

Dr. Valmassy is a Past Professor and Past Chairman of the Department of Podiatric Biomechanics at the California College of Podiatric Medicine. He is a staff podiatrist at the Center for Sports Medicine at St. Francis Memorial Hospital in San Francisco.




References:

1. D’Amico JC. Developmental flatfoot. In Volpe RL (ed.): Introduction to podopediatrics. Churchill Livingstone, New York, 2001, pp. 257-73.

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