Temporal changes in gait parameters and muscle activation during sustained walking in children with spastic cerebral palsy

Abstract

Objective Temporal changes in spatiotemporal gait parameters and muscle activation may reflect progressive gait deterioration during prolonged walking in children with spastic cerebral palsy. Methods A portable gait analysis system and surface electromyography were used to evaluate gait characteristics during a 3-minute walking protocol in 15 children with SCP and 15 age-matched healthy controls. Participants walked at a self-selected speed on a level surface. Spatiotemporal gait parameters, energy expenditure, and bilateral gastrocnemius and tibialis anterior muscle activation were assessed at predefined time points. Linear mixed-effects models were applied to examine group-by-time interactions while accounting for repeated measurements within participants. Results Linear mixed-effects model analysis revealed significant Group × Time interactions for stance phase, swing phase, step length, lower-limb forward acceleration, foot clearance angle, and walking velocity (all P < 0.05), indicating divergent temporal trajectories between children with SCP and healthy controls. No significant Group × Time interactions were observed for single-step time, gait cycle duration, or cadence (all P > 0.05). For energy expenditure, a significant Group × Time interaction (P = 0.047) indicated that the SCP group maintained elevated metabolic cost into the third minute while controls exhibited a declining trajectory. Similarly, significant Group × Time interactions were observed for bilateral gastrocnemius (P = 0.002) and tibialis anterior (P = 0.006) normalized root mean square amplitudes, reflecting a greater temporal decline in muscle activation in the SCP group from the second minute onward. Conclusion Children with SCP may exhibit gradual changes in spatial-temporal gait parameters and muscle activation patterns during the later stages of a long walking task. These findings suggest that selected gait and EMG parameters in children with SCP begin to change after approximately 2 min of continuous walking, indicating a potential time window for closer monitoring or structured rest breaks during rehabilitation. Further studies incorporating direct fall-risk assessment and validated fatigue measures are warranted before definitive clinical recommendations can be made.