Post-stroke Hemiplegic Gait: New Perspective and Insights

Abstract

Walking dysfunction occurs at a very high prevalence in stroke survivors. Human walking is a phenomenon often taken for granted, but it is mediated by complicated neural control mechanisms. The automatic process includes the brainstem descending pathways (RST and VST) and the intraspinal locomotor network. It is known that leg muscles are organized into modules to serve subtasks for body support, posture and locomotion. Major kinematic mechanisms are recognized to minimize the center of gravity (COG) displacement. Stroke leads to damage to motor cortices and their descending corticospinal tracts and subsequent muscle weakness. On the other hand, brainstem descending pathways and the intraspinal motor network are disinhibited and become hyperexcitable. Recent advances suggest that they mediate post-stroke spasticity and diffuse spastic synergistic activation. As a result of such changes, existing modules are simplified and merged, thus leading to poor body support and walking performance. The wide range and hierarchy of post-stroke hemiplegic gait impairments is a reflection of mechanical consequences of muscle weakness, spasticity, abnormal synergistic activation and their interactions. Given the role of brainstem descending pathways in body support and locomotion and post-stroke spasticity, a new perspective of understanding post-stroke hemiplegic gait is proposed. Its clinical implications for management of hemiplegic gait are discussed. Two cases are presented as clinical application examples.

Ankle and Foot Spasticity Patterns in Chronic Stroke Survivors with Abnormal Gait

“…Despite a general presentation of extensor spasticity in the lower extremity, there is no typical ankle and foot deformity in post-stroke hemiplegia. Similar to various spastic hemiplegic gait patterns, this versatility of ankle and foot spasticity involvement reflects that ankle and foot deformity is a mechanical consequence between muscle spasticity, weakness, and its interactions with the ground reaction forces [ 6 ].…”

Mechanical and energetic determinants of impaired gait following stroke: segmental work and pendular energy transduction during treadmill walking

“…arms, head and trunk) have been implicated in increasing the mechanical energy cost of the system following stroke (Olney et al, 1986). Further studies are needed to better understand how the wide range of post-stroke hemiplegic gait impairments may reflect the mechanical consequences of muscle weakness, spasticity, abnormal synergistic activation, and their interactions (Li et al, 2018).…”

Walking characteristics including mild motor paralysis and slow walking speed in post-stroke patients

“…It is important to note that the kinematic characteristics of walking disorders may be strongly influenced by central neurological deficits. Therefore, both kinetic and neurological factors need to be considered 13 . Neurological factors that affect walking speed include motor paralysis, sensory disorder, and muscle spasticity, leading to a decrease in stride length and trunk stability and an increase in asymmetry, all of which can limit walking speed [14][15][16] .…”