Prescribing Effective Orthotics For Pediatric Patients

Pages: 24 - 27
Author(s): 
Guest Clinical Editor: Robert Eckles, DPM

These expert panelists discuss orthotic considerations for pediatric flatfoot, when prefab devices can be helpful and other factors in the treatment of pediatric patients.

Q:

While pain is always the dominant factor in making decisions around pediatric flatfoot, what objective clinical criteria exist that, even in the absence of severe symptoms, validate the prescription of a custom foot orthosis?

A:

Robert Eckles, DPM, asserts that there are clinical scenarios that fit squarely into the “must treat” category while the child is asymptomatic.

“Sometimes it’s ‘you know it when you see it’ but I think gross deviations from ‘normal’ — as noted by spasm, extreme hypermobility, the presence of proximal deformity or symptoms — clearly justify an intervention directed at the lower extremity,” notes Dr. Eckles.

He adds that it may also be of clinical significance when there is marked planal dominance, which may be a predictor of future difficulty.

For Russell Volpe, DPM, a comprehensive assessment of the severity and the consequences of the deformity is paramount in assessing asymptomatic pediatric flatfoot. Saying the moderate to severe flatfoot is often an at-risk foot, he looks at the deformity in the context of other comorbidities and risk factors such as family history, body weight, superstructural influences (torsion and equinus chief among them) and other medical factors such as laxity. Dr. Volpe also looks for signs that structural changes are already occurring. These changes may include early juvenile hallux valgus, overlapping digits and visible strain on tendons and other soft tissues.

In the diverse pediatric age groups of his practice, Paul Jordan, DPM, finds that localized or focal foot pain is an infrequent complaint by a young child. More often, he says parents do observe a foot posture that either concerns them or a family member. In the 7 to 8 years of age and older population, Dr. Jordan says pain as a foot complaint may increase and is more frequent in the adolescent ages. He adds this pain often does not occur in isolation but along with other associated lower limb complaints.  

During the time spent in taking a history, Dr. Jordan notes parents frequently leave out information that may very well determine if the child might benefit from foot orthoses. Yet he says the parents may note that children fatigue easily, ask to be carried, trip and fall more often than age-matched peers, or may avoid activities that involve being on their feet to play. Similarly, Dr. Volpe looks at ways the child may already be compromised by the presence of the flatfoot. Examples of what he looks for include self-selecting out of physical activities, symptoms or changes in behavior that may be a result of the poor foot alignment.

“Even though these concerns are more subjective, it is important to hear what is of concern to a parent regarding his or her child so we might assist the parent in understanding which issues fall within the realm of typical for his or her youngster at a particular age,” says Dr. Jordan.

More commonly, Dr. Jordan says the pain is often proximal over larger muscle groups in comparison to “growing pains” in late afternoon or those that awaken a child at night. As he explains, these pains do not occur during periods of growth but more often during steady anticipated growth. Dr. Jordan notes the “flatfoot” that does need to be addressed will have concomitant proximal malalignment of the hip-knee-ankle-foot linkages or coupling during weightbearing activities. Dr. Jordan says appropriately designed foot orthoses almost always relieve overuse and resulting muscle spasms, or night pains if pathomechanics are to blame. While parental reporting is not necessarily objective criteria, he says reports that the child “no longer wakes in pain” at night is often sufficient validation.

Excessive pronation is a poor postural position that sets the stage for future deformity and dysfunction, according to Joseph D’Amico, DPM, who says excessive pronation is abnormal at any age and should be neutralized. He notes the absence of pedal symptomatology in the pediatric patient is not a predictor of optimum foot function or alignment.

Excessive pronation not only affects the foot but negatively impacts the knee, hip and back, emphasizes Dr. D’Amico. Additionally, he says the excessively pronated foot pathologically disturbs normal gait mechanics, extending the midstance phase and reducing the propulsive phase. In the beginning walker, he says this may serve as a detriment to speedy locomotor maturation.

“So it’s not just a question of whether the child has foot pain to determine if treatment should be instituted but whether this condition is concomitantly producing symptomatology, dysfunction, malalignment or postural derangement in the superstructure as well,” says Dr. D’Amico.

Dr. D’Amico notes we can determine the question as to how “excessive” pronation is according to the tenet of Tax, whose philosophy was that “if you can see it, it’s excessive.”1 According to Dr. D’Amico, Schuster stated that the lowering of the navicular upon weightbearing or a “navicular drop” of more than 3/8 inches or 9 mm with or without pain is an indication for treatment.2  

Objective signs of excessive pronation include talar prominence, the “too many toes” sign, marked calcaneal eversion, medial border convexity and lateral concavity, normal arch off-weightbearing and absence upon loading, says Dr. D’Amico. He suggests examining footwear for signs of abnormal wear and/or distortion. Dr. D’Amico notes additional criteria may include: a family history of foot pathology, ligamentous laxity, obesity and systemic disease including syndrome and neurological disorders as well as inflammatory joint disease.

Generalized joint hypermobility associated with generalized ligamentous laxity is a measure that Dr. Jordan says one can objectively assess and record using criteria such as the modified Beighton criteria. He cites a correlation between high Beighton scores and tripping/falling, persistent toe-toe walking thought to be idiopathic, late day or evening thigh and leg cramps, or pains and so on. The child with global laxity of ligaments, Dr. Jordan notes, rarely has foot pain but almost always has a “flat appearing” foot type. In this instance, he says a custom fabricated foot orthosis can supplement the loss of pedal joint integrity stemming from hyperextensible, hyperelastic ligaments failing to afford internal joint constraints.  

Q:

Many DPMs utilize a formula popularized on the West Coast years ago to assist in determining if a patient is hitting important milestones. Do you now find this formula valid and applicable?

A:

The formula in question would be that the maximum amount of resting valves that can be considered normal for a child up to age 7 is 7 degrees minus the age of the child.3 Dr. Volpe finds it useful to “frame” if a child is pronated more than this “admittedly arbitrary” standard for what is an acceptable or normal amount of pronation at a particular age under 7. He does not make a decision to treat or not to treat based on this formula alone, but says it can be useful to determine if a child is above the threshold of normal and if so, by how much. Then Dr. Volpe will evaluate all the other factors (biomechanical, historical, functional, familial) that go into deciding if and how to treat.

Ideally, Dr. D’Amico says he would prefer that the relaxed or resting calcaneal stance position be vertical. However, in light of developmental immaturity in terms of ligamentous laxity, he notes neurologic and osseous immaturity and osseous malalignment present in varying degrees in all children up to approximately 6 years of age. He accepts 3 or 4 degrees of calcaneal eversion upon weightbearing provided no other signs of excessive pronation are present and/or additional compounding factors are present. Dr. D’Amico in essence agrees with the 7-Age guide but only in children from 3 ½ to 7 years of age.3

As Dr. Eckles notes, the 7-Age guide is a “best judgment” that parallels what most podiatric physicians would consider normal developmental observation.3 In other words, with time, most pediatric flatfoot resolves by the age of 9 or 10. Having said that, he asserts the formula is “simplistic … and may instill confidence in delaying treatment when in fact with a more detailed exam, treatment may well be the most appropriate path.”

“Frankly, I never found such simplistic and static measures to be of value even if the measure is closely correlated with radiographic findings, which it is not,” concurs Dr. Jordan. “There are many more significant variables in this equation to consider rather than to rely on this poor measure as being a criteria of developmental normalcy.”

Dr. Jordan notes recent attempts to confirm or deny the reliability of clinical observations and clinical measure of everted or valgus calcaneus during static weightbearing through comparative, weightbearing 3D computed tomography (CT) demonstrated anatomical varus rather than valgus in kids with “flatfeet” rather than valgus as clinically perceived. He suspects that DPMs generally measure soft tissue displacement on the frontal plane rather than true varus/valgus while the younger child with abundant calcaneal fat stands.

Q:

Under what conditions do you feel prefabricated orthoses are indicated in children?

A:

Dr. Eckles finds many prefab devices “quite useful and effective” when the deviation from “norm” is mild or moderate. However, he says non-custom orthoses are not suitable when treating the adductus foot, the foot attached to a low tibial torsion limb or when significant equinus is present. In these cases, he says prefab devices will likely not be sufficiently supportive and conform to the anatomy to manage the stresses, nor can they be counted on to remediate forefoot deformity. As a guide for the patient and parent’s expectations, Dr. Eckles says prefabricated orthoses may also be useful. Treatment failure with such a device should not be a rationale for abandonment of conservative care, notes Dr. Eckles.

Dr. Volpe will use prefab devices in the pre-propulsive toddler, particularly in cases of mild deformity. As severity and age increase, he is more likely to recommend custom orthoses so he can better address the myriad of factors identified in the comprehensive assessment of the child and the child’s lower extremity. In some (rare) cases, Dr. Volpe may recommend a prefabricated device as a trial to see if the device provides improvement and short-term relief, and then he reassesses for a possible upgrade to custom orthoses depending on circumstances.

Although Dr. D’Amico does not employ prefabricated orthoses for children or adults, he notes there are many serviceable and improved forms on the market. Those devices with a deepened heel seat and medial and lateral flanges with some degree of rearfoot posting incorporated into a non-deforming, non-compressible shell will be helpful for most children but since no two feet are the same, he says such devices cannot be specific for anyone.

Dr. D’Amico adds that due to phlylogenic and ontogenic influences, most children have some degree of frontal plane forefoot deformity that non-custom orthoses do not address. Additionally, not only is it true that no two feet are the same from child to child, he says it is also an extremely rare occurrence when two feet are identical right to left. Therefore, since all prefabs are identical in their shape and alignment right to left, Dr. D’Amico emphasizes that they cannot provide optimum alignment and function on an individual basis.

With the exception of using a gait plate simply to alter the medial or lateral lever of the foot during the terminal stance phase of walking, Dr. Jordan argues there is no indication for fitting a preconceived, predesigned “container” for soft tissues that envelope the pediatric foot. If the young patient is in need of or can benefit from foot orthoses, supramalleolar orthoses or ankle-foot orthoses (AFO), he asserts that making that child fit into an exoskeleton thought to be “average” is “not best medical practice.”

“If the desire is to ‘treat parents,’ then fashionable footwear to ‘hide’ the feet seems more appropriate, functioning by the ‘out of sight, out of mind’ method,” says Dr. Jordan.

Dr. D’Amico is a Professor and Past Chairman in the Division of Orthopedics at the New York College of Podiatric Medicine. He is a Diplomate of the American Board of Podiatric Medicine, and a Fellow of the American Academy of Foot and Ankle Pediatrics. Dr. D’Amico is in private practice in New York City.

Dr. Eckles is the Dean of Clinical Studies and an Associate Professor in the Department of Orthopedics and Pediatrics at the New York College of Podiatric Medicine. Dr. Volpe is affiliated with the Foot Center of New York in New York City.

Dr. Jordan is in private practice in Smithtown, NY.

Dr. Volpe is a Professor in the Department of Orthopedics and Pediatrics at the New York College of Podiatric Medicine in New York City. He is in private practice in New York City and Farmingdale, N.Y. He is also a Diplomate of the American Board of Podiatric Medicine.

References

  1. Tax HR. Excessively pronated feet: A health hazard to developing children. Child Adolesc Soc Work J. 1993; 10(5):431–40.
  2. D’Amico JC. Shuster RO. A biomechanical icon (part I). Podiatry Management. 2013; 129-137.
  3. Valmassy RL. Clinical Biomechanics of the Lower Extremities, First Edition, Mosby, St. Louis, 1995.

For further reading, see “Point-Counterpoint: Asymptomatic Pediatric Flatfoot: Should You Treat It?” in the December 2014 issue of Podiatry Today, “Pediatric Flatfoot: When Do You Treat It?” in the January 2012 issue, or “Key Insights On Surgical Correction Of Pediatric And Adult Flatfoot” in the January 2007 issue.

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