What Affects Symptoms in Kids with Flatfoot?

Pes planovalgus (flatfoot) is a common condition seen in the pediatric orthopaedic clinic. We who help manage this condition differentiate it from adult acquired flatfoot deformity, primarily in that most child and adolescent patients remain asymptomatic or minimally symptomatic and rarely require surgical intervention. However, it would be nice to have data to share with young patients and their parents regarding factors associated with flatfoot symptoms.

Min et al. provide some of that data in the September 2, 2020 issue of The Journal. The authors retrospectively evaluated factors affecting the symptoms of idiopathic pes planovalgus among 123 patients (mean age of 10.1 ± 3.2 years) using the 4-domain Oxford Ankle Foot Questionnaire (OxAFQ) administered to patients and their parents. They compared questionnaire scores to 3 radiographic measurements─anteroposterior (AP) talo-first metatarsal angle, lateral talo-first metatarsal angle, and hallux valgus angles. They also analyzed the scores in relation to patient age and sex.

Min et al. found that the physical domain score for the child-reported OxAFQ decreased by 0.74 with each 1° increase in the AP talo-first metatarsal angle. Because that angle is a surrogate for forefoot abduction, this finding portends worse patient-reported outcomes in kids with greater severity of that component of flatfoot. Female sex was also associated with lower physical domain scores, with the authors postulating that this might be attributable to culturally influenced sex differences.

In addition, age was a significant factor in 3 domains of the OxAFQ. Compared with scores from younger kids, children ≥10 years old and their parents reported statistically worse outcomes with regard to school/play, emotional well-being, and footwear. In other words, at or beyond the age of 10, flatfoot deformity seems to significantly affect the patient’s choice of footwear, interferes with the ability to participate in sports and play, and may cause personal distress, such as that which comes from being teased about foot appearance.

Orthopaedists can help manage most cases of pediatric flatfoot with sound footwear recommendations and reassurance. But it appears that in the setting of increased forefoot abduction, female sex, and symptoms that persist past the age of 10 years, further investigation may be warranted. Although this study has weaknesses, it shows that there may be detriments─both physical and emotional─associated with pes planovalgus in pediatric patients that should not be ignored.

Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media