Expert Insights On Prescribing Pediatric Orthotics
There is an array of special considerations one must take into account when prescribing pediatric orthotics. In addition, it is important to work with both children and their parents to encourage compliance so the child does not develop problems later in life. With this in mind, our expert panelists share their experience on prescribing pediatric orthotics. Q: When prescribing an orthotic for a child, how do you explain to the parents that the child may need to wear these devices for many years or the rest of his or her life? A: Alona Kashanian, DPM, uses a kid glove approach when discussing any type of treatment or therapy with parents. She educates her patient’s parents about the genetic component of the child’s foot and ankle problem. Dr. Kashanian notes these parents often have worn corrective devices or corrective shoes as children themselves so they are familiar with the treatment. She assures the parents she will follow up with the child on a six- to 12-month basis in order to assess the effectiveness of the orthotics. However, she also points out that just as eyeglasses do not change a person’s eye but help prevent further eye problems, a pair of orthotics will prevent further damage and slow down the progression of the pathology. Ronald Valmassy, DPM, also uses this analogy with parents, saying orthotics will compensate for problems and allow a child to exercise or participate in sporting activities comfortably without any secondary injuries. When prescribing pediatric orthotics, Dr. Valmassy tells parents he may utilize a device for a few years while monitoring the child’s development and may stop utilizing the device at a specific point. However, he also notes that some patients may need to wear these devices for the rest of their lives. Since most of the parents’ concern is that they will need to change the orthotics annually, Richard Jay, DPM, points out that orthotics usually last anywhere between two and three years. During some instances in the early growth patterns, between about 1 and 1/2 to 2 and 1/2 years, he says the orthotic does have to be changed. However, Dr. Jay says if you properly explain the need to control the foot and maintain it in the corrected neutral position, parents “usually have no problem understanding the need for replacement.” Dr. Jay adds that most of the orthotic laboratories provide a protection type plan that allows patients’ parents to pay just the cost of casting and replace the orthotics as needed. Until the age of 7, the child’s foot is continuing to unwind from in utero positions and Russell Volpe, DPM, explains to parents that he will reassess the need for orthoses once children outgrow them. Dr. Volpe emphasizes that the sooner the child starts orthotic therapy, the greater the chances of influencing the shape of the arch and the development of the foot permanently. “However, I am careful not to tell them that if devices are worn early on, then a child will not need them later when he or she is older,” cautions Dr. Volpe. “Certainly, many toddlers and young school age children who need, and benefit from, motion controlling orthoses continue to benefit from them as they get older.” In the absence of symptoms, Dr. Volpe says one must carefully evaluate the structure and function of the foot in order to determine whether the patient should continue orthotic therapy. Q: How do you improve compliance in a child? What do you advise the parent who states the child doesn’t like to wear orthotics? A: For the most part, once children have worn an orthotic device for a brief time, Dr. Valmassy has discovered they actually like wearing it. Parents will commonly return for follow-up visits and tell him children are very consistent with moving their orthotics from shoe to shoe. Occasionally, Dr. Valmassy says patients may have a problem with fit or the hardness of the orthotic. If the problem is a poorly fitting shoe, changing the shoe may make the orthotic feel more comfortable. In regard to the hardness of the orthotic, Dr. Valmassy says applying a soft topcoat to the devices often makes the orthotic more comfortable. Initially, Dr. Kashanian always uses a prefabricated polypropylene orthotic for children. She notes many labs carry a range of low profile pediatric prefabricated orthotics that are not bulky. Prefabricated orthotics allow children to adjust to a device in their shoes and Dr. Kashanian says the devices can be delivered in two or three days. She advises parents to encourage gradual wear initially and a slow break-in period for the orthotic. If the orthotics are well constructed, Dr. Jay says children should be able to tolerate them. However, he notes that sometimes orthotics may cause discomfort if they are too long in the plantar aspect and extend distally under the metatarsal heads. If the orthotic extends to the metatarsal head region just proximally, children should not have a problem, according to Dr. Jay. Children also may experience irritation on the medial or lateral side of the foot if there is a deep seated heel cup or if the orthotic has deep medial or lateral phalanges. However, Dr. Jay suggests remedying those problems by grinding down the phalanges. Likewise, Dr. Volpe also has experienced few problems with compliance or tolerance. He says kids usually have good toleratation to orthotics that are prescribed to control motion in high motion, flexible feet. When a carefully prescribed device is made by a quality lab from a well-executed negative impression, Dr. Volpe says there is usually few problems. Dr. Kashanian says a little humor doesn’t hurt when prescribing pediatric orthotics. “I tell my pediatric patients that the orthotics will make them as fast as Superman or as quick as Michael Jordan,” says Dr. Kashanian. However, Dr. Volpe tells parents to downplay the presence of the orthotic in the shoe. He finds children do not like being asked how the devices feel too frequently so he suggests that parents not ask about the orthotic as children are likely to relay any problems. Dr. Volpe also instructs parents to check children’s feet for irritation to identify problems during the break-in period. Q: What type of orthotic do you prescribe for a juvenile bunion? Does it make a difference to you if the foot is skeletally mature or not? A: Although more outcomes evidence is needed on the subject, Dr. Volpe says the existing evidence suggests starting an orthotic very early in the pathogenesis of a condition will provide the greatest likelihood of a device improving foot malalignments and decreasing hallux abducto valgus progression. He often prescribes an orthotic for a teenager with a skeletally mature foot. In such a case, Dr. Volpe says the role of the device shifts to stabilizing the foot and abnormal motions of the first ray rather than to trying to slow down the progression of the deformity. In Dr. Kashanian’s experience, a child who has a juvenile bunion usually has a hypermobile forefoot. She accordingly uses an aggressive device to limit the medial column forces on the first ray. If the child’s foot is not skeletally mature, she will prescribe a polypropylene device with a deep heel cup, extra wide arch and minimal arch cast fill. Dr. Kashanian also incorporates a medial heel skive and inverts the positive cast, depending on the resting calcaneal position. She says the rearfoot post should be ground with 4/4 motion. However, if the foot is skeletally mature, she uses the same type of orthotic but incorporates a standard arch fill. In addition to the orthotic prescription, Dr. Kashanian discusses with the patient’s parents the appropriate shoes needed for this very flexible foot type. Dr. Jay agrees with the approach of choosing an orthotic that will control the foot type that is causing the juvenile bunion. For example, when there is an accompanying flatfoot deformity, he prescribes an extra depth heel seat with a phalange both medially and laterally that contour to the foot and limit the amount of pronatory changes. He finds a rearfoot varus post to be sufficient in most cases. “I do not feel that skeletal maturity has anything to do with this,” says Dr. Jay. “If the orthotic is contoured properly to the foot, there is usually minimal complaint from the child.” Dr. Valmassy also tries to determine both the etiology of the abnormal foot function and the extent of abnormal pronation. Accordingly, Dr. Valmassy always prescribes orthotic devices that fully address abnormal foot function. He does not feel the skeletal maturity of the child’s foot is an issue. Dr. Valmassy uses an orthotic device that is functional in nature once the child develops a heel toe propulsive type of gait pattern, which typically occurs at the age of 3 or 4. An important adjunct to treating juvenile bunion problems in adolescents is initiating exercises that strengthen the abductor hallucis brevis muscle. Dr. Valmassy says doing so complements the overall use of the orthotic device. Q: What type of orthotic do you prescribe for Sever’s disease (calcaneal apophysitis)? A: The main complaint of children with calcaneal apophysitis is usually pain upon ambulation because the tendo Achilles is too tight and there is compression at the closing growth plate, according to Dr. Jay. If symptoms are mild to moderate, he usually prescribes a temporary heel rise to the insert. He prefers not to go any higher than 1/4 to 1/2 inch and usually recommends placing the rise into a high-heeled sneaker. Dr. Volpe prefers using a device with a deep heel seat to cup and hold the plantar fat pad under the calcaneus. While the material should be relatively non-compressible to limit abnormal motions and contain the fat pad, Dr. Volpe says it should not be too rigid as this may increase irritation to the apophysis. He notes other options include incorporating a heel cushion on the dorsal surface of the shell and adding heel lifts for equinus influences when appropriate. When it comes to Sever’s disease, Dr. Valmassy will make specific modifications such as fully addressing the extent of abnormal pronation and asking for a deeper heel cup. He often utilizes a combination of materials (PPT, Spenco or EVA) in the heel portion of the orthotic to provide increased shock absorbtion. Often, Dr. Valmassy asks the laboratory to create a “sweet spot,” an aperture built into the body of the orthotic device, which will then be lined with PPT and covered with another softer material. Utilizing heel lifts, Korex or other suitable materials often helps in such cases, according to Dr. Valmassy. He adds there is a correlation of this process with tight posterior musculature. When children experience tightness of the posterior musculature, Dr. Valmassy says regular stretching exercises, night splints and possible referral to a physical therapist may be important adjuncts. For patients with Sever’s disease, Dr. Kashanian prescribes a polypropylene device with a deep heel cup and a wide width, which allows more surface area to cup the heel. She recommends a biateral heel lift, which one should grind down gradually over a four- to five-week period. Dr. Kashanian also recommends using a topcover such as 1/8 nylene (Spenco-like material) with a 1/8 poron heel cushion. The rearfoot post should be out of EVA or Birkocork to allow maximum shock absorption at heel strike, according to Dr. Kashanian. She also emphasizes the need for a stable shoe along with the appropriate orthotic. Q: What type of orthotic do you prescribe for a flexible metatarsus adductus foot type? What if the patient is less than 8 years old? What if the patient is a teenager? A: If a metatarsus adductus is flexible and reducible, Dr. Volpe says one can treat this with an orthosis designed around a rectus positive model. If the adductus is reduced in the positive model, he recommends incorporating a shell with a high and long medial flange — extending at least to the first metatarsal head, sometimes further to the hallux — pressed to the positive model. He says this will produce a device that holds the foot out of adductus. With these patients, Dr. Volpe says it is important to accommodate for a potentially prominent styloid process in the negative casting and shell design/accommodations for the orthoses. Dr. Volpe says one may take this approach regardless of age as long as the deformity is flexible and the device can reduce the deformity. He adds that issues with prominence of the styloid and consequent irritation seem to be greater with increasing age. Like Dr. Volpe, Dr. Valmassy would use a similar device for a child under 8 that he would employ for a teenager. Dr. Valmassy says he would fully address the abnormal foot mechanics and utilize a shoe that would accommodate the orthotic, possibly utilizing some in-shoe buttressing along the medial margin of the hallux to decrease some of the pull of the abductor hallucis brevis. In a child under 8 who demonstrates a flexible metatarsus adductus foot type, Dr. Kashanian recommends using an aggressive device to prevent breakdown and collapse of the midtarsal joint, which would result in a skewed foot. As the child becomes more ambulatory and active, Dr. Kashanian says the midtarsal joint begins to break down, unlock and pronate as a compensatory mechanism. To prevent unlocking, she advises using a combination of a medial heel skive with an inversion cast technique. When casting such a patient, Dr. Kashanian has found that casting out as much of the soft tissue supinatus out at the first metatarsal base area is helpful along with the traditional technique of holding the subtalar joint in neutral and locking the midtarsal joint. Dr. Kashanian prefers to prescribe a vacuum-formed polypropylene device with a deep heel cup and a high medial flange. Vacuum-formed polypropylene, unlike a milled CAD-CAM device, contours better to the C-shaped lateral curvature of the metatarsus adductus foot type, according to Dr. Kashanian. She recommends a minimum cast arch fill, a medial heel skive and inverting the cast, depending on the degree of metatarsus. Dr. Kashanian says one should prescribe the rearfoot post of the orthotic with no lateral bevel. She notes this foot type has excessive lateral column loading and the unbeveled rearfoot post will offload the lateral column while allowing the medial heel skive and inversion to help the midtarsal and subtalar joint. For teenage patients, Dr. Kashanian recommends using a deep device with a wide width and a standard arch cast fill. She says all other items of the prescription would be identical to her treatment for a younger child. For children under 8 or 9, Dr. Jay not only creates a cast in the neutral position but holds the foot in the corrected abducted position at the same time. As he explains, this stabilizes the calcaneus in its neutral 0-degree position and abducts the forefoot on the rearfoot, reducing the metatarsus adductus deformity. The result is a negative cast of the foot in a corrected abducted position. Dr. Jay subsequently sends this to the laboratory with instructions to create an orthotic with a deep medial and lateral phalange, and a deep seated heel in a 5-degree rearfoot post. Since children older than 8 or 9 usually have a prominent fifth metatarsal base, Dr. Jay advises cutting out the first metatarsal base area of the phalange in order to prevent any irritation or abutment into the orthotic. Editor’s Note: The second part of this column will appear in the April 2005 issue of Podiatry Today. Dr. Feit is a Fellow of the American College of Foot and Ankle Surgeons, and practices privately in San Pedro and Torrance, Calif. He is the Past President of the Los Angeles chapter of the American Diabetes Association. Dr. Jay is a Fellow of the American College of Foot and Ankle Surgeons. He is a Professor of Foot and Ankle Surgery at the Temple University School of Podiatric Medicine, and is board-certified in foot and ankle surgery. Dr. Jay practices at Cumberland Orthopedics in Vineland, N.J. Dr. Kashanian is a Diplomate of the American Board of Primary Medicine and Podiatric Orthopedics, and is a consultant for ProLab Educational Institute. She is also in private practice in Northridge, Calif. Dr. Valmassy is a 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. Dr. Volpe is a Professor in the Departments of Pediatrics and Orthopedics and Chair of the Department of Pediatrics at the New York College of Podiatric Medicine. He has a pediatric foot and ankle specialty private practice in Farmingdale and New York, N.Y.