Kinematic and Functional Gait Changes After the Utilization of a Foot Drop Stimulator in Pediatrics

Abstract

Foot drop is one of the most common secondary conditions associated with hemiplegia post stroke and cerebral palsy (CP) in children, and is characterized by the inability to lift the foot (dorsiflexion) about the ankle. This investigation focuses on children and adolescents diagnosed with brain injury and aims to evaluate the orthotic and therapeutic effects due to continuous use of a foot drop stimulator (FDS). Seven children (10 ± 3.89 years) with foot drop and hemiplegia secondary to brain injury (stroke or CP) were evaluated at baseline and after 3 months of FDS usage during community ambulation. Primary outcome measures included using mechanistic (joint kinematics, toe displacement, temporal-spatial asymmetry), and functional gait parameters (speed, step length, time) to evaluate the orthotic and therapeutic effects. There was a significant correlation between spatial asymmetry and speed without FDS at 3 months (r = 0.76, p < 0.05, df = 5) and no correlation between temporal asymmetry and speed for all conditions. The results show orthotic effects including significant increase in toe displacement (p < 0.025 N = 7) during the swing phase of gait while using the FDS. A positive correlation exists between toe displacement and speed (with FDS at 3 months: r = 0.62, p > 0.05, without FDS at 3 months: r = 0.44, p > 0.05). The results indicate an orthotic effect of increased dorsiflexion and toe displacement during swing with the use of the FDS in children with hemiplegia. Further, the study suggests that there could be a potential long-term effect of increased dorsiflexion during swing with continuous use of FDS.

Keywords: cerebral palsy; foot drop; functional electrical stimulation; gait; hemiplegia; pediatric rehabilitation; stroke.

FIGURE 1

Subject wearing the FDS.

FIGURE 2

Mean ± Standard deviation (SD) ankle plantarflexion/dorsiflexion of the (A) affected ankle with FDS, (B) affected ankle without FDS (C) unaffected ankle with FDS and (D) unaffected ankle without FDS, at baseline and 3 months of all participants. The black line represents the mean ankle plantarflexion/dorsiflexion of one representative healthy child. The dots represent the start of swing phase.

FIGURE 3

Mean ± Standard deviation (SD) knee plantarflexion/dorsiflexion of the (A) affected knee with FDS, (B) affected knee without FDS (C) unaffected knee with FDS and (D) unaffected knee without FDS, at baseline and 3 months of all participants. The black line represents the mean knee plantarflexion/dorsiflexion of one representative healthy child. The dots represent the start of swing phase.

FIGURE 4

Mean ± Standard deviation (SD) hip plantarflexion/dorsiflexion of the (A) affected hip with FDS, (B) affected hip without FDS (C) unaffected hip with FDS and (D) unaffected hip without FDS, at baseline and 3 months of all participants. The black line represents the mean hip plantarflexion/dorsiflexion of one representative healthy child. The dots represent the start of swing phase.

FIGURE 5

(A) Mean ± Standard error of toe displacement of the affected side with and without FDS. (B) Mean ± Standard error of walking speed for the affected side with and without FDS.

FIGURE 6

Correlation between toe displacement and speed of the affected side with and without FDS at baseline and 3 months.

FIGURE 7

(A) Overall asymmetry of the affected side with and without FDS at baseline and 3 months. (B) Spatial asymmetry of the affected side with and without FDS at baseline and 3 months. (C) Correlation between temporal asymmetry and speed of the affected side with and without FDS at baseline and 3 months. (D) Correlation between spatial asymmetry and speed of the affected side with and without FDS at baseline and 3 months.