Nervous System Diseases Commons^™

Multi-Site Identification And Generalization Of Clusters Of Walking Behaviors In Individuals With Chronic Stroke And Neurotypical Controls, Natalia Sánchez, Nicolas Schweighofer, Sara J. Mulroy, Ryan T. Roemmich, Trisha M. Keshar, Gelsy Torres-Oviedo, Beth E. Fisher, James M. Finley, Carolee J. Winstein

Physical Therapy Faculty Articles and Research

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Background

Walking patterns in stroke survivors are highly heterogeneous, which poses a challenge in systematizing treatment prescriptions for walking rehabilitation interventions.

Objectives

We used bilateral spatiotemporal and force data during walking to create a multi-site research sample to: (1) identify clusters of walking behaviors in people post-stroke and neurotypical controls and (2) determine the generalizability of these walking clusters across different research sites. We hypothesized that participants post-stroke will have different walking impairments resulting in different clusters of walking behaviors, which are also different from control participants.

Methods

We gathered data from 81 post-stroke participants across 4 research sites and …

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Identifying The Neural Correlates Of Anticipatory Postural Control: A Novel Fmri Paradigm, Jo Armour Smith, Rongwen Tain, Kelli G. Sharp, Laura M. Glynn, Linda R. Van Dillen, Korinne Henslee, Jesse V. Jacobs, Steven C. Cramer

Physical Therapy Faculty Articles and Research

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Altered postural control in the trunk/hip musculature is a characteristic of multiple neurological and musculoskeletal conditions. Previously it was not possible to determine if altered cortical and subcortical sensorimotor brain activation underlies impairments in postural control. This study used a novel fMRI-compatible paradigm to identify the brain activation associated with postural control in the trunk and hip musculature. BOLD fMRI imaging was conducted as participants performed two versions of a lower limb task involving lifting the left leg to touch the foot to a target. For the supported leg raise (SLR) the leg is raised from the knee while the …

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Kinematic Assessment Of Turning And Walking Tasks Among Stroke Survivors By Employing Wearable Sensors And Pressure Platform, Masoud Abdollahi, Pranav Madhav Kuber, Christopher Hoang, Michael Shiraishi, Rahul Soangra, Ehsan Rashedi

Physical Therapy Faculty Articles and Research

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Stroke survivors often experience reduced movement capabilities due to alterations in their neuromusculoskeletal systems. Modern sensor technologies and motion analyses can facilitate the determination of these changes. Our work aims to assess the potential of using wearable motion sensors to analyze the movement of stroke survivors and identifying the affected functions. We recruited 10 participants (5 stroke survivors, 5 healthy individuals) and conducted a controlled laboratory evaluation for two of the most common daily activities: turning and walking. Among the extracted kinematic parameters, range of trunk and sacrum lateral bending in turning were significantly larger in stroke survivors (p-value<0.02). However, no statistical difference in mean angular velocity and range of motion for trunk/sacrum/shank flexion-extension were obtained in the turning task. Our results also indicated that during walking, while there was no difference in swing time, double support portion of gait among the stroke group was significantly larger (p-value = 0.001). Outcomes of this investigation may help in designing new rehabilitation programs for stroke and other neurological disorders and/or in improving the efficacy of such programs.Clinical Relevance— This study may provide a better insight on the detailed functional differences between stroke survivors and healthy individuals which in turn could be used to develop a more efficient rehabilitation program for stroke community.

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Self-Paced Treadmills Do Not Allow For Valid Observation Of Linear And Nonlinear Gait Variability Outcomes In Patients With Parkinson’S Disease, Maryam Rohafza, Rahul Soangra, Jo Armour Smith, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

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Background

Due to the imposed constant belt speed, motorized treadmills are known to affect linear and nonlinear gait variability outcomes. This is particularly true of patients with Parkinson’s Disease where the treadmill can act as an external pacemaker. Self-paced treadmills update the belt speed in response to the subject's walking speed and might, therefore, be a useful tool for measurement of gait variability in this patient population. This study aimed to compare gait variability during walking at self-paced and constant treadmill speeds with overground walking in individuals with PD and individuals with unimpaired gait.

Methods

Thirteen patients with Parkinson’s Disease …

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Does Subthalamic Deep Brain Stimulation Impact Asymmetry And Dyscoordination Of Gait In Parkinson’S Disease?, Deepak K. Ravi, Christian R. Baumann, Elena Bernasconi, Michelle Gwerder, Niklas K. Ignasiak, Mechtild Uhl, Lennart Stieglitz, William R. Taylor, Navrag B. Singh

Physical Therapy Faculty Articles and Research

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Background. Subthalamic deep brain stimulation (STN-DBS) is an effective treatment for selected Parkinson’s disease (PD) patients. Gait characteristics are often altered after surgery, but quantitative therapeutic effects are poorly described. Objective. The goal of this study was to systematically investigate modifications in asymmetry and dyscoordination of gait 6 months postoperatively in patients with PD and compare the outcomes with preoperative baseline and to asymptomatic controls without PD. Methods. A convenience sample of thirty-two patients with PD (19 with postural instability and gait disorder (PIGD) type and 13 with tremor dominant disease) and 51 asymptomatic controls participated. Parkinson patients …

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Gains Across Who Dimensions Of Function After Robot-Based Therapy In Stroke Subjects, Jennifer Wu, Lucy Dodakian, Jill See, Erin Burke Quinlan, Lisa Meng, Jeby Abraham, Ellen C. Wong, Vu Le, Alison Mckenzie, Steven C. Cramer

Physical Therapy Faculty Articles and Research

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Background

Studies examining the effects of therapeutic interventions after stroke often focus on changes in loss of body function/structure (impairment). However, improvements in activities limitations and participation restriction are often higher patient priorities, and the relationship that these measures have with loss of body function/structure is unclear.

Objective

This study measured gains across WHO International Classification of Function (ICF) dimensions and examined their interrelationships.

Methods

Subjects were recruited 11 to 26 weeks after hemiparetic stroke. Over a 3-week period, subjects received 12 sessions of intensive robot-based therapy targeting the distal arm. Each subject was assessed at baseline and at 1 …

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Predicting Gains With Visuospatial Training After Stroke Using An Eeg Measure Of Frontoparietal Circuit Function, Robert J. Zhou, Hossein M. Hondori, Maryam Khademi, Jessica M. Cassidy, Katherine M. Wu, Derek Z. Yang, Nikhita Kathuria, Fareshte R. Erani, Lucy Dodakian, Alison Mckenzie, Cristina V. Lopes, Walt Scacchi, Ramesh Srinivasan, Steven C. Cramer

Physical Therapy Faculty Articles and Research

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The heterogeneity of stroke prompts the need for predictors of individual treatment response to rehabilitation therapies. We previously studied healthy subjects with EEG and identified a frontoparietal circuit in which activity predicted training-related gains in visuomotor tracking. Here we asked whether activity in this same frontoparietal circuit also predicts training-related gains in visuomotor tracking in patients with chronic hemiparetic stroke. Subjects (n = 12) underwent dense-array EEG recording at rest, then received 8 sessions of visuomotor tracking training delivered via home-based telehealth methods. Subjects showed significant training-related gains in the primary behavioral endpoint, Success Rate score on a standardized test …

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Can Gait Signatures Provide Quantitative Measures For Aiding Clinical Decision-Making? A Systematic Meta-Analysis Of Gait Variability Behavior In Patients With Parkinson’S Disease, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

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A disturbed, inconsistent walking pattern is a common feature of patients with Parkinson's disease (PwPD). Such extreme variability in both temporal and spatial parameters of gait has been associated with unstable walking and an elevated prevalence of falls. However, despite their ability to discretise healthy from pathological function, normative variability values for key gait parameters are still missing. Furthermore, an understanding of each parameter's response to pathology, as well as the inter-parameter relationships, has received little attention. The aim of this systematic literature review and meta-analysis was therefore to define threshold levels for pathological gait variability as well as to …

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Revealing The Quality Of Movement: A Meta-Analysis Review To Quantify The Thresholds To Pathological Variability During Standing And Walking, Niklas König Ignasiak

Physical Therapy Faculty Articles and Research

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Neuromotor processes are inherently noisy, which results in variability during movement and fluctu-ations in motor control. Although controversial, low levels of variability are traditionally considered healthy, while increased levels are thought to be pathological. This systematic review and meta-analysisof the literature investigates the thresholds between healthy and pathological task variability.

After examining 13,195 publications, 109 studies were included. Results from over 3000 healthy sub-jects and 2775 patients revealed an overall positive effect size of pathology on variability of 0.59 forwalking and 0.80 for sway. For the coefficient of variation of stride time (ST) and sway area (SA), upperthresholds of 2.6% …

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Connectivity Measures Are Robust Biomarkers Of Cortical Function And Plasticity After Stroke, Jennifer Wu, Erin Burke Quinlan, Lucy Dodakian, Alison Mckenzie, Nikhita Kathuria, Robert J. Zhou, Renee Augsburger, Jill See, Vu H. Lee, Ramesh Srinivasan, Steven C. Cramer

Physical Therapy Faculty Articles and Research

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Valid biomarkers of motor system function after stroke could improve clinical decision-making. Electroencephalography-based measures are safe, inexpensive, and accessible in complex medical settings and so are attractive candidates. This study examined specific electroencephalography cortical connectivity measures as biomarkers by assessing their relationship with motor deficits across 28 days of intensive therapy. Resting-state connectivity measures were acquired four times using dense array (256 leads) electroencephalography in 12 hemiparetic patients (7.3 ± 4.0 months post-stroke, age 26–75 years, six male/six female) across 28 days of intensive therapy targeting arm motor deficits. Structural magnetic resonance imaging measured corticospinal tract injury and infarct volume. …

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