The Effects of Stroke Type, Locus, and Extent on Long-Term Outcome of Gait Rehabilitation

Abstract

Background Paresis in stroke is largely due to damage to descending corticospinal and corticobulbar pathways. Recovery of paresis predominantly reflects the impact on the neural consequences of this white matter lesion by reactive neuroplasticity (mechanisms involved in spontaneous recovery) and experience-dependent neuroplasticity, driven by therapy and daily experience. However, both theoretical considerations and empirical data suggest that type of stroke (large vessel distribution/lacunar infarction, hemorrhage), locus and extent of infarction (basal ganglia, right hemisphere cerebral cortex), and the presence of leukoaraiosis or prior stroke might influence long-term recovery of walking ability. In this secondary analysis based on the 408 participants in the Locomotor Experience Applied Post-Stroke (LEAPS) study database, we seek to address these possibilities. Methods Lesion type, locus, and extent were characterized by the two neurologists in the LEAPS trial on the basis of clinical CT and MRI scans. A series of regression models was employed to test our hypotheses regarding the effects of lesion type, locus, extent, and laterality on 2–12 month change in gait speed, controlling for baseline gait speed, age, and Berg Balance Scale score. Results Gait speed change at 1-year was significantly reduced in participants with basal ganglia involvement and prior stroke. There was a trend toward reduction of gait speed change in participants with lacunar infarctions. The presence of right hemisphere cortical involvement had no significant impact on outcome. Conclusions Type, locus, and extent of lesion, and the loss of substrate for neuroplastic effect due to prior stroke may impact long-term outcome of rehabilitation of hemiparetic gait.

Leukoaraiosis Predicts Short-term Cognitive But not Motor Recovery in Ischemic Stroke Patients During Rehabilitation

“…Leukoaraiosis has been found to predict global functional outcomes in multiple studies 4, 7, 8 but there is paucity of data on domain specific outcomes. 29,31 Our results provide novel insight into this issue by suggesting a domain specific impact of leukoaraiosis on stroke recovery with preexisting leukoaraiosis severity relating to impaired recovery early after stroke predominantly through cognitive impairment.…”

Stroke Lesions in a Large Upper Limb Rehabilitation Trial Cohort Rarely Match Lesions in Common Preclinical Models

“…Evidence in support of this theory comes from recent stroke recovery studies in humans suggesting that deep white matter lesions affecting the corticospinal tract (CST) cause much of the hemiparesis following stroke 26,27 . This evidence was somewhat corroborated by neuroimaging data from patients with lower extremity weakness enrolled in a recent multicenter trial that showed high rates of lacunar infarction 28 . Lesion size may affect motor outcome in those with subcortical stroke 29 .…”

Ventilatory threshold may be a more specific measure of aerobic capacity than peak oxygen consumption rate in persons with stroke

“…A directed acyclic graph approach 27 was used to determine which variables would be appropriate to use to adjust for the effects of true aerobic capacity and aid in isolating the distorting effect of motor function on the aerobic capacity measures. Based on the literature, we identified the following potential common causes of both motor dysfunction (lower CGS) and lower aerobic capacity measurement: greater stroke severity, 20,28-30 increased age, 3,31 female sex, 3,31 higher BMI, 3,32,33 depression 34,35 and lower physical activity history. 1,3,20 Hypothesized causal relationships were graphed with unidirectional arrows (Figure 2).…”