The use of the foot orthoses in the treatment of paediatric flat foot: an evidence based overview

University Degree Subjects allied to Medicine

Advanced Orthotic Science – CW 1 Sonia Singh

ID: 200865328

Clinical Review

Introduction

Flatfoot in the paediatric population is a common concern and is presented regularly in paediatric health-care settings. (1) Despite this, there is no universally excepted definition for this condition, although consistent attributes include a valgus heel and a flattened medial longitudinal arch. (2) Other names frequently used include pes planus, (1) hypermobile flatfoot, (3,4) and pronated foot. (10) The lack of a standard definition of this condition, a wide spectrum of severity and the many different etiologies for flatfoot make it difficult to differentiate normal from pathologic foot thus to compare the results of treatment. (5)

A range of conservative interventions have been reported in the literature from advice to foot orthoses, stretching exercises, footwear selection and modifications, serial casting and appropriate weight reductions. (1) This clinical review however, will focus on the use of foot orthoses as it is very frequently prescribed and there is much controversy surrounding its use. There is a common agreeance between clinicians that symptomatic children should be treated to reduce pain and prevent further deformity. (2,4,6,7,) The controversy relates to those that are asymptomatic and they consist of a larger proportion of the paediatric population. (2,8) Many studies have produced undeniable conclusions that foot orthoses do not modify the natural development of flatfoot. (8-11)

Methods

The literature was reviewed to identify studies that investigated the use of foot orthoses as part of conservative treatment of paediatric flatfoot. The literature was then structured keeping in mind with the hierarchical levels of evidence. (2) The focus of this review was on randomized controlled trials as they have a strong level of evidence (2). Optimum level of evidence comes from a systematic review based on a meta-analysis of a variety of randomized controlled trials (1) however, since there is only one current study by Rome et al. (1) which is still in progress and so cannot be included in this review. Since there is a relative lack of randomized controlled trials in this area, three case series will be included as they are specific to the use of foot orthoses. Although the level of evidence is not as strong as randomized controlled trials, they can still provide useful evidence.

Given that there is no universally accepted definition for flatfoot, (11-13) we included studies that referred to flatfoot as “pronated foot”, “pes planus”, or “hypermobile flatfoot”. Although flatfoot can exist as an isolated pathology, it can also be part of a larger pathology such as ligamentous laxity, neurological or muscular abnormalities, genetic syndromes and collagen disorders. (1,5)

Sources and selection criteria

This review was prepared by searching the following databases: Medline 1966-present; AMED; CINAHL via Clinicians Health Channel; Cochrane library; Pubmed and Google Scholar. Key words used were “paediatric”, flatfoot”, and “foot orthoses”.

The electronic search was complemented by the following:

Checking of reference lists of relevant articles for additional studies reported;
Searches of abstracts in conference proceedings and special issues of journals;
Correspondence letters by professionals working in the area of topic using BMJ.

Classification

This is a preview of the whole essay

The electronic search was complemented by the following:

Checking of reference lists of relevant articles for additional studies reported;
Searches of abstracts in conference proceedings and special issues of journals;
Correspondence letters by professionals working in the area of topic using BMJ.

Classification

Flatfoot may be classified as flexible (physiologic) or rigid (pathologic) on the basis of its etiology, clinical features, natural history, and potential for causing disability. (7) Flexible flatfoot is a benign condition and is thought by some to be an anatomical variant related to ligament laxity (9) where the arch flattens on weight-bearing and reappears upon non-weight-bearing and toe-standing. (7) These feet are hypermobile with flexible talo-calcaneal joints and may or may not have an associated contracture of the Achilles tendon. (5) Flexible flatfoot may be asymptomatic or symptomatic. (6) Asymptomatic flexible flatfoot should be monitored clinically for onset of symptoms and signs of progression. (6) Symptomatic flexible flatfoot produces subjective complaints such as pain along the medial side of the foot, pain in the sinus tarsi, leg and knee, and everted heels. (6) Rigid flatfoot is characterized by a lowered medial longitudinal arch on both weight-bearing and non-weight-bearing and by stiffness of the rearfoot and midfoot. It occurs mostly in children with some underlying pathology, tends to persist, and frequently causes disability. (6,7)

Diagnosis

An understanding of the normal evolution of the medial longitudinal arch in the child’s foot is very important when diagnosing. (6,13) When the child is born, the foot is in a calcaneo valgus position with no longitudinal arch apparent but a pad of fat on the medial side as shown in figure 1. (13) The arch starts to develop after the age of about 2-3 years where this flat arch is considered normal (13) and develops progressively over the first decade of life. (5) According to Fixsen, (13) the most useful test in diagnosing flexible from rigid flatfoot is the great toe extension test (Jack’s test) in which, when the child is asked to stand on their tip toes, the medial arch appears, heel goes into varus and the tibia externally rotates. (13) If these occur then most certainly the clinician is dealing with a flexible flatfoot and not pathological.

Figures used from Fixsen 1998 published in the Journal of the Royal Society of Medicine.

Results

Table 1 summarizes the two randomized control trials which is the best available research addressing the use of foot orthoses for paediatric flatfoot. (9,10) Whitford and Esterman, 2007 (10) conducted a randomized parallel, single-blinded, controlled trial of custom-made and prefabricated orthoses on 178 children between the ages of 7 and 11 years with “flexible excess pronation”. The diagnosis was based on calcaneal eversion and navicular drop. Outcomes included gross motor proficiency, self perception, exercise efficiency, and pain. Since pain in the lower limb is used as a critical criterion for provision of orthoses, (10) pain was measured using a visual analogue scale at baseline and follow-up. Analysis of data of children with pain found no evidence of the effectiveness of orthoses for pain relief.

Abbreviations: UCBL, University of California Biomechanics Laboratory. Table 1. Comparison of two existing randomized controlled trials for foot orthoses and paediatric flatfoot. There are notable differences between the studies, e.g. Subject ages and outcome measures. Table derived from Evans 2008.

Wenger et al. (9) conducted a prospective study to determine whether treatment can influence flatfoot in children. Ninety-eight children between the ages of 1 and 6 years were assigned to 4 groups; control, orthopaedic shoes, Helfet heel cup and custom-made orthoses. The diagnosis was based on a valgus position of the heel and poor medial arch formation. The flexibility of the condition was tested by asking children to perform Jack’s test (figure 2). Radiographs and photographs of the feet were taken at baseline and follow-up 6-monthly, for at least 3 years in all patients. To assess clinical improvement, baseline results were compared with the most recent follow-up. There appeared to be no structural benefit to the foot when compared with the control.

Table 2. Characteristics of the studies at the Lowest Level of Evidence. Derived from Evans 2008. (2)

Discussion

On comparing the custom-made and prefabricated orthoses groups with the control group, there were no statistically significant differences found in any of the outcomes measured. According to Whitford and Esterman, (10) there appears to be very little justification on the use of foot orthoses (whether custom or prefabricated) for paediatric flatfoot.

Wenger et al. The results of their study showed that flexible flatfoot in children naturally improves over a three-year period and wearing foot orthoses does not affect the degree of improvement. Thus they do not recommend foot orthoses for the typical flexible flatfoot for children between the ages of 1-6.

Case series conducted on the use of foot orthoses for treatment of flatfoot are outlined in Table 2 below. Bleck & Berzins (14) conducted a study on 122 children with the use of the UCBL insert and Helfet heel cup however, they did not randomly assign the patients or have matching controls. (9) Bordelon (3) treated 50 children with custom-made inserts and reported improvements in the talometatarsal angles as measured on radiographs. Since only 22 patients completed the study and no controls were included, the evaluation of significance of these results difficult.

Overall, these studies consist of small samples, have different age groups, and lack control groups for comparison with the foot orthoses intervention groups. Due to their poor research designs, none of these studies provide results that can be generalized to the paediatric flatfoot population and these positive results could have occurred by chance. (2)

Conclusion

The literature to date is relatively meagre, as there are no long-term longitudinal studies of orthotic intervention on paediatric flatfoot. Many papers shed light on the prevalence of the problem and the debate surrounding the treatment for flexible flatfoot.

In 1989, Wenger et al. (9) concluded that wearing foot orthoses provide no long-term functional benefit and children should not be burdened with them. However, orthoses are still prescribed very frequently with no high-level evidence that they improve function or reduce pain. (10) In summary, it can be concluded that there is a lack of good-quality research available for the clinician. Poor-quality research provides limited results and can be misleading for the clinicians who require well-substantiated studies to guide them. (2)

Total word count (excluding information boxes and reference list): 1,447 words

References

Rome K, Ashford RI, Evans A. Non-surgical interventions for paediatric pes planus (Protocol). The Cochrane Library 2009;1

Evans AM. The Flat-Footed Child-To Treat or Not to Treat? J Am Podiatr Med Assoc 2008 Sep/Oct;98(5):386-393.

Bordelon RL. Correction of hypermobile flatfoot in children by molded insert. Foot and Ankle 1980;1(3):143-150.

Bordelon RL. Hypermobile flatfoot in children: comprehension, evaluation and treatment. Clin Orthop Relat Res 1983 Dec;181:7-14.

Capello, T. Song, KM. Determining treatment of flatfeet in children. Current Opinion in Paediatrics 1998;10:77-81.

Harris EJ, Vanore JV, Thomas JL, Kravitz SR, Mendelson SA, Mendicino RW et al. Diagnosis and treatment of pediatric flatfoot. J Foot Ankle Surg 2004 Nov/Dec;43(6):341-371.

Staheli LT. Planovalgus foot deformity. J Am Podiatr Med Assoc 1999;89(2):94-99.

Pfeiffer M, Kotz R, Ledl T, Hauser G, Sluga M. Prevalence of flat foot in preschool-aged children. Pediatrics 2006 Aug;118(2):634-639.

Wenger DR, Maudlin D, Speck G, Morgan D, Lieber RL. Corrective shoes and inserts as treatment for flexible flatfoot in infants and children. J Bone Joint Surg Am 1989;71(6):800-810.

Whitford D, Esterman A. A randomized controlled trial of two types of in-shoe orthoses in children with flexible excess pronation of the feet. Foot and Ankle Int 2007 Jun;28(6):715-722.

Riccio I. Gimigliano F. Gimigliano R. Porpora G. Iolascon G. Rehabilitative treatment in flexible flatfoot: a perspective cohort study. Musculoskelet Surg 2009;93:101-107.

Napolitano C, Walsh S, Mahoney L, McCrea J. Risk factors that may adversely modify the natural history of the pediatric pronated foot. Clin Podiatr Med Surg 2000 Jul;17(3):397-417.