The relationship between quality of life and foot function in children with flexible flatfeet

•We undertook gait analysis of children with flat and neutral foot postures.•Kinematic angles were correlated with quality of life.•Children with symptomatic flatfeet walked slower with reduced stride length.•Children with flatfeet had increased hindfoot eversion and forefoot supination.•Forefoot supination correlated the strongest with quality of life measures.

Flat feet in children are common, and at times symptomatic, but the relationship between function and symptoms or impairment is still unclear. We undertook a prospective, observational study comparing children with paediatric flexible flat foot (PFF) and children with neutral feet (NF) using three dimensional gait analysis (3DGA). It was hypothesised that children with PFF would demonstrate differences in both spatio-temporal parameters of gait and foot and ankle kinematics compared to the NF group and that these differences would correlate with impaired quality of life (QoL). The kinematic differences were expected to be most marked in hindfoot coronal plane motion and forefoot sagittal and transverse plane motion. Eighty-three children between the ages of 8 and 15 were recruited in this study: Forty-two were classified as having PFF and forty-one as NF. Each child underwent 3DGA and completed the Oxford Ankle Foot Questionnaire for Children (OxAFQ_C). Reduced OxAFQ_C physical domain scores in the PFF children were associated with slower walking speed (p = 0.014) and reduced normalised stride length (p = 0.008). PFF children also demonstrated significantly increased hindfoot eversion and forefoot supination during gait. Significant differences between groups were not observed for other foot and ankle joint motions. Increased maximum hindfoot eversion and increased forefoot supination correlated strongly with lower QoL scores in PFF children. These data further our understanding of the functional characteristics that lead to impaired QoL in PFF children. These findings will help guide the surveillance and management of children with this ubiquitous condition.