Evaluation of Individualized Functional Electrical Stimulation-Induced Acute Changes during Walking: A Case Series in Children with Cerebral Palsy

Abstract

Functional electrical stimulation (FES) walking interventions have demonstrated improvements to gait parameters; however, studies were often confined to stimulation of one or two muscle groups. Increased options such as number of muscle groups targeted, timing of stimulation delivery, and level of stimulation are needed to address subject-specific gait deviations. We aimed to demonstrate the feasibility of using a FES system with increased stimulation options during walking in children with cerebral palsy (CP). Three physical therapists designed individualized stimulation programs for six children with CP to target participant-specific gait deviations. Stimulation settings (pulse duration and current) were tuned to each participant. Participants donned our custom FES system that utilized gait phase detection to control stimulation to lower extremity muscle groups and walked on a treadmill at a self-selected speed. Motion capture data were collected during walking with and without the individualized stimulation program. Eight gait metrics and associated timing were compared between walking conditions. The prescribed participant-specific stimulation programs induced significant change towards typical gait in at least one metric for each participant with one iteration of FES-walking. FES systems with increased stimulation options have the potential to allow the physical therapist to better target the individual’s gait deviations than a one size fits all device.

Neuromuscular electrical stimulation to augment lower limb exercise and mobility in individuals with spastic cerebral palsy: A scoping review

“…Limitations of this scoping review include the exclusion of some NMES-related studies that did not meet inclusion criteria due to NMES treatment duration of fewer than 4 weeks, the absence of an exercise component, technology development trials for NMES-assisted gait on a treadmill ( Zahradka et al, 2021 ) or robotics ( Shideler et al, 2020 ). These limitations may have eliminated some evidence in the field.…”

Personalized strategies of neurostimulation: from static biomarkers to dynamic closed-loop assessment of neural function

“…In any case, the number of studies on the usage of closed loop neuroengineering systems for neuroscientific investigation and/or as means of neurological therapy, both in animal experimentation and pre-clinical/clinical trials, have been steadily increasing over the years. It has been now demonstrated that, in fact, application of electrical stimulation which is directly determined, in real time, by recorded electrophysiological activity can: promote both plasticity and motor recovery in the cases of stroke or traumatic brain injury (i.e., TBI) ( Cheng et al, 2014 ); induce significant changes in walking performances in cerebral palsy ( Zahradka et al, 2021 ); block pathological activity and promote the physiological one within the damaged tissue on Parkinson’s disease ( Rosin et al, 2011 ) or epilepsy ( Berényi et al, 2012 ; Skarpaas et al, 2019 ; Cota et al, 2021 ), and promote motor recovery after spinal cord injury ( Ganzer et al, 2018 ). For the treatment of Parkinson’s disease, researchers usually monitor the power of the beta band to trigger DBS, such as the work of Little and colleagues ( Little and Brown, 2012 ; Little et al, 2013 ).…”

Case report: The gait deviation index may predict neurotherapeutic effects of FES-assisted gait training in children with cerebral palsy

“…When recommendations differed, a consensus stimulation strategy was defined through discussion by considering the best compromise to improve gait kinematics and walking speed. Stimulation amplitude and pulse duration were set for each muscle group and gait phase, individually, to address subject-specific gait deviations as prescribed by the PTs' evaluation and determined in a procedure called thresholding (27,28); the thresholding procedure and individualized stimulation protocol for each participant can be found in Appendices A and B, respectively. At any time during training or assessments, if the participant experienced excessive exhaustion or discomfort (verbally communicated) or the operators noticed such behavior, the physical therapist stopped the treadmill immediately with an emergency stop button.…”

“…For example, stimulation of both rectus femoris and vastus lateralis muscles were more effective in improving posture than stimulation of each muscle alone during walking in one child with CP (25). Three recent multi-channel FES-assisted walking studies demonstrated positive immediate (26,27) and training effects (28) on joint angles of a total of nine individuals with CP. However, as expected, the improvements are variable across the individuals, joints and phases of gait.…”

“…The dosage and the training protocol were based on the FastFES gait training paradigm proposed by Binder-Macleod and colleagues (29). The multi-channel FES system used during training was designed and evaluated by our group (27,28,(30)(31)(32) and included the flexibility to provide individualized stimulation to address subject-specific gait deviations. The FES system had the capability to detect all seven phases of gait and to stimulate up to 5 muscle groups for each leg during each gait phase.…”