Lower limb muscle activity underlying temporal gait asymmetry post-stroke. Issue 8 (August 2020)

• Record Type: Journal Article
• Authors: Rozanski, Gabriela M.; Huntley, Andrew H.; Crosby, Lucas D.; Schinkel-Ivy, Alison; Mansfield, Avril; Patterson, Kara K.
• Is Part Of: Clinical neurophysiology. Volume 131:Issue 8(2020:Aug.)
• Page Start: 1848
• Page End: 1858
• Publication Date: 2020-08
• Subjects: Stroke -- Gait asymmetry -- Electromyography -- Swing time; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2020.04.171
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: The asymmetric group exhibited fewer dorsiflexor muscle bursts during swing. More affected side plantarflexor activity in stance ended early with asymmetry. Dorsiflexor on/off time of the asymmetric participants differed from controls. Abstract: Objective: Asymmetric walking after stroke is common, detrimental, and difficult to treat, but current knowledge of underlying physiological mechanisms is limited. This study investigated electromyographic (EMG) features of temporal gait asymmetry (TGA). Methods: Participants post-stroke with or without TGA and control adults (n = 27, 8, and 9, respectively) performed self-paced overground gait trials. EMG, force plate, and motion capture data were collected. Lower limb muscle activity was compared across groups and sides (more/less affected). Results: Significant group by side interaction effects were found: more affected plantarflexor stance activity ended early (p = .0006) and less affected dorsiflexor on/off time was delayed (p < .01) in persons with asymmetry compared to symmetric and normative controls. The TGA group exhibited fewer dorsiflexor bursts during swing (p = .0009). Conclusions: Temporal patterns of muscular activation, particularly about the ankle around the stance-to-swing transition period, are associated with TGA. The results may reflect specific impairments or compensations that affect locomotor coordination. Significance: Neuromuscular underpinnings of spatiotemporal asymmetry have not been previously characterized. These novel findings may inform targeted therapeutic strategies to improve gait quality after stroke.