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Stroke

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Full-Text Articles in Biomedical Engineering and Bioengineering

Association Of Bovine Arch Anatomy With Incident Stroke After Transcatheter Aortic Valve Replacement, Gerardo V. Lo Russo, Hasan S. Alarouri, Abdulah Al-Abcha, Brennan Vogl, Abdulah Mahayni, Agata Sularz, Hoda Hatoum, Jeremy Collins, Juan A. Crestanello, Mohamad Alkhouli Feb 2024

Association Of Bovine Arch Anatomy With Incident Stroke After Transcatheter Aortic Valve Replacement, Gerardo V. Lo Russo, Hasan S. Alarouri, Abdulah Al-Abcha, Brennan Vogl, Abdulah Mahayni, Agata Sularz, Hoda Hatoum, Jeremy Collins, Juan A. Crestanello, Mohamad Alkhouli

Michigan Tech Publications, Part 2

BACKGROUND: Acute ischemic stroke complicates 2 % to 3 % of transcatheter aortic valve replacements (TAVRs). This study aimed to identify the aortic anatomic correlates in patients after TAVR stroke. METHODS AND RESULTS: This is a single-center, retrospective study of patients who underwent TAVR at the Mayo Clinic between 2012 and 2022. The aortic arch morphology was determined via a manual review of the pre-TAVR computed tomography images. An "a priori" approach was used to select the covariates for the following: (1) the logistic regression model assessing the association between a bovine arch and periprocedural stroke (defined as stroke within …


Unobtrusive Assessment Of Upper-Limb Motor Impairment Using Wearable Inertial Sensors, Brandon R. Oubre Oct 2022

Unobtrusive Assessment Of Upper-Limb Motor Impairment Using Wearable Inertial Sensors, Brandon R. Oubre

Doctoral Dissertations

Many neurological diseases cause motor impairments that limit autonomy and reduce health-related quality of life. Upper-limb motor impairments, in particular, significantly hamper the performance of essential activities of daily living, such as eating, bathing, and changing clothing. Assessment of impairment is necessary for tracking disease progression, measuring the efficacy of interventions, and informing clinical decision making. Impairment is currently assessed by trained clinicians using semi-quantitative rating scales that are limited by their reliance on subjective, visual assessments. Furthermore, existing scales are often burdensome to administer and do not capture patients' motor performance in home and community settings, resulting in a …


Quantifying And Reversing Compensatory Movements By Persons Post-Stroke In The Ambient Setting, Aaron Miller Dec 2021

Quantifying And Reversing Compensatory Movements By Persons Post-Stroke In The Ambient Setting, Aaron Miller

Doctoral Dissertations

Nearly 800,000 people in the United States suffer stroke annually. Following the onset of stroke, survivors will exhibit deficits, such as hemiplegia, which will limit their function and ability to perform activities of daily living (ADLs). In order to regain independence, many stroke survivors will employ maladaptive compensatory strategies to help with the completion of tasks. Compensation is generally defined as any performance of a task that is different than the way it may have been performed before the onset of a neurodegenerative disorder. While for some severely impaired individuals, compensation may be necessary, for most these maladaptive strategies ultimately …


Biomechanically Inspired Assistive Technology To Restore Movement Of The Upper Limbs After Stroke, Ariel Thomas Jan 2021

Biomechanically Inspired Assistive Technology To Restore Movement Of The Upper Limbs After Stroke, Ariel Thomas

Graduate Theses, Dissertations, and Problem Reports

A stroke often damages the neural structures responsible for movement. Stroke is a heterogeneous disease, affecting each survivor differently. There are common motor features of a stroke, but even these features vary across time as an individual proceeds through different stages of recovery. The different ways in which stroke motor impairment can present itself are often overlooked, but these differences are fundamental to the understanding of the disease and its recovery. When motor assessments are capable of acquiring information necessary to parse out a detailed profile of each stroke case, this will lead to an improved neuromechanical understanding of the …


Eeg Characterization Of Sensorimotor Networks: Implications In Stroke, Dylan Blake Snyder Apr 2020

Eeg Characterization Of Sensorimotor Networks: Implications In Stroke, Dylan Blake Snyder

Dissertations (1934 -)

The purpose of this dissertation was to use electroencephalography (EEG) to characterize sensorimotor networks and examine the effects of stroke on sensorimotor networks. Sensorimotor networks play an essential role in completion of everyday tasks, and when damaged, as in stroke survivors, the successful completion of seemingly simple motor tasks becomes fantasy. When sensorimotor networks are impaired as a result of stroke, varying degrees of sensorimotor deficits emerge, most often including loss of sensation and difficulty generating upper extremity movements. Although sensory therapies, such as the application of tendon vibration, have been shown to reduce the sensorimotor deficits after stroke, the …


Reaching Performance In Heathy Individuals And Stroke Survivors Improves After Practice With Vibrotactile State Feedback, Valay A. Shah Apr 2020

Reaching Performance In Heathy Individuals And Stroke Survivors Improves After Practice With Vibrotactile State Feedback, Valay A. Shah

Dissertations (1934 -)

Stroke causes deficits of cognition, motor, and/or somatosensory functions. These deficits degrade the capability to perform activities of daily living (ADLs). Many research investigations have focused on mitigating the motor deficits of stroke through motor rehabilitation. However, somatosensory deficits are common and may contribute importantly to impairments in the control of functional arm movement. This dissertation advances the goal of promoting functional motor recovery after stroke by investigating the use of a vibrotactile feedback (VTF) body-machine interface (BMI). The VTF BMI is intended to improve control of the contralesional arm of stroke survivors by delivering supplemental limb-state feedback to the …


Indirect Structural Connectivity As A Biomarker For Stroke Motor Recovery, Miguel Renato Sotelo Munoz Apr 2020

Indirect Structural Connectivity As A Biomarker For Stroke Motor Recovery, Miguel Renato Sotelo Munoz

Dissertations (1934 -)

In this dissertation project, we demonstrated that diffusion magnetic resonance imaging and measures of indirect structural brain connectivity are sensitive to changes in fiber integrity and connectivity to remote regions in the brain after stroke. Our results revealed new insights into the effects local lesions have on global connectivity—in particular, the cerebellum—and how these changes in connectivity and integrity relate to motor impairment. We tested this methodology on two stroke groups—subacute and chronic—and were able to show that indirect connectivity is sensitive to differences in connectivity during stroke recovery. Our work can inform clinical methods for rehabilitating motor function in …


Early Acid/Base And Electrolyte Changes In Permanent Middle Cerebral Artery Occlusion: Aged Male And Female Rats, Sarah R. Martha, Lisa A. Collier, Stephanie M. Davis, Sarah J. Goodwin, David Powell, Doug Lukins, Justin F. Fraser, Keith R. Pennypacker Jan 2020

Early Acid/Base And Electrolyte Changes In Permanent Middle Cerebral Artery Occlusion: Aged Male And Female Rats, Sarah R. Martha, Lisa A. Collier, Stephanie M. Davis, Sarah J. Goodwin, David Powell, Doug Lukins, Justin F. Fraser, Keith R. Pennypacker

Neurosurgery Faculty Publications

BACKGROUND: Early changes in acid/base and electrolyte concentrations could provide insights into the development of neuropathology at the onset of stroke. We evaluated associations between acid/base and electrolyte concentrations, and outcomes in permanent middle cerebral artery occlusion (pMCAO) model.

METHODS: 18-month-old male and female Sprague-Dawley rats underwent pMCAO. Pre-, post- (7 min after occlusion), and at 72 hr of pMCAO venous blood samples provided pH, carbon dioxide, oxygen, glucose, hematocrit, hemoglobin, and electrolyte values of ionized calcium, potassium, and sodium. Multiple linear regression determined predictors of infarct and edema volumes from these values, Kaplan-Meier curve analyzed morality between males and …


Seeing Eye To Eye: A Machine Learning Approach To Automated Saccade Analysis, Maigh Attre May 2019

Seeing Eye To Eye: A Machine Learning Approach To Automated Saccade Analysis, Maigh Attre

Honors Scholar Theses

Abnormal ocular motility is a common manifestation of many underlying pathologies particularly those that are neurological. Dynamics of saccades, when the eye rapidly changes its point of fixation, have been characterized for many neurological disorders including concussions, traumatic brain injuries (TBI), and Parkinson’s disease. However, widespread saccade analysis for diagnostic and research purposes requires the recognition of certain eye movement parameters. Key information such as velocity and duration must be determined from data based on a wide set of patients’ characteristics that may range in eye shapes and iris, hair and skin pigmentation [36]. Previous work on saccade analysis has …


Tactile-Star: A Novel Tactile Stimulator And Recorder System For Evaluating And Improving Tactile Perception, Giulia Ballardini, Giorgio Carlini, Robert A. Scheidt, Ilana Nisky, Maura Casadio Apr 2018

Tactile-Star: A Novel Tactile Stimulator And Recorder System For Evaluating And Improving Tactile Perception, Giulia Ballardini, Giorgio Carlini, Robert A. Scheidt, Ilana Nisky, Maura Casadio

Biomedical Engineering Faculty Research and Publications

Many neurological diseases impair the motor and somatosensory systems. While several different technologies are used in clinical practice to assess and improve motor functions, somatosensation is evaluated subjectively with qualitative clinical scales. Treatment of somatosensory deficits has received limited attention. To bridge the gap between the assessment and training of motor vs. somatosensory abilities, we designed, developed, and tested a novel, low-cost, two-component (bimanual) mechatronic system targeting tactile somatosensation: the Tactile-STAR—a tactile stimulator and recorder. The stimulator is an actuated pantograph structure driven by two servomotors, with an end-effector covered by a rubber material that can apply two different …


Muscle Coordination Contributes To Function After Stroke; Proprioception Contributes To Control Of Posture, Movement, Maria Bengtson Oct 2017

Muscle Coordination Contributes To Function After Stroke; Proprioception Contributes To Control Of Posture, Movement, Maria Bengtson

Dissertations (1934 -)

More than half of stroke survivors experience persistent upper extremity motor impairments that can negatively impact quality of life and independence. Effective use of the upper extremity requires coordination of agonist/antagonist muscle pairs, as well as coordination of multiple control actions for stabilizing and moving the arm. In this dissertation, I present three studies in which I recorded isometric torque production, single joint movement and stabilization, and clinical measures of function and impairments after stroke to evaluate the extent to which changes in coordination of agonist/antagonist muscles and of sequential control actions contribute to deficits after stroke. In Aim 1, …


The Arm Movement Detection (Amd) Test: A Fast Robotic Test Of Proprioceptive Acuity In The Arm, Leigh A. Mrotek, Maria Bengtson, Tina M. Stoeckmann, Lior Botzer, Claude Ghez, John Mcguire, Robert A. Scheidt Jun 2017

The Arm Movement Detection (Amd) Test: A Fast Robotic Test Of Proprioceptive Acuity In The Arm, Leigh A. Mrotek, Maria Bengtson, Tina M. Stoeckmann, Lior Botzer, Claude Ghez, John Mcguire, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Background

We examined the validity and reliability of a short robotic test of upper limb proprioception, the Arm Movement Detection (AMD) test, which yields a ratio-scaled, objective outcome measure to be used for evaluating the impact of sensory deficits on impairments of motor control, motor adaptation and functional recovery in stroke survivors.

Methods

Subjects grasped the handle of a horizontal planar robot, with their arm and the robot hidden from view. The robot applied graded force perturbations, which produced small displacements of the handle. The AMD test required subjects to respond verbally to queries regarding whether or not they detected …


Erratum To: Supplemental Vibrotactile Feedback Control Of Stabilization And Reaching Actions Of The Arm Using Limb State And Position Error Encodings, Alexis Krueger, Psiche Giannoni, Valay Shah, Maura Casadio, Robert A. Scheidt May 2017

Erratum To: Supplemental Vibrotactile Feedback Control Of Stabilization And Reaching Actions Of The Arm Using Limb State And Position Error Encodings, Alexis Krueger, Psiche Giannoni, Valay Shah, Maura Casadio, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

The original article contained omissions mistakenly carried forward by the Production department handling this journal; these omissions related to missing ‘λ’ symbols throughout the article body, thus inaccurately representing the meaning of the associated text.

The article has now been updated to include these symbols in the appropriate sections of text to accurately reflect the conveyed implications.


Supplemental Vibrotactile Feedback Control Of Stabilization And Reaching Actions Of The Arm Using Limb State And Position Error Encodings, Alexis Krueger, Psiche Giannoni, Valay Shah, Maura Casadio, Robert A. Scheidt May 2017

Supplemental Vibrotactile Feedback Control Of Stabilization And Reaching Actions Of The Arm Using Limb State And Position Error Encodings, Alexis Krueger, Psiche Giannoni, Valay Shah, Maura Casadio, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Deficits of kinesthesia (limb position and movement sensation) commonly limit sensorimotor function and its recovery after neuromotor injury. Sensory substitution technologies providing synthetic kinesthetic feedback might re-establish or enhance closed-loop control of goal-directed behaviors in people with impaired kinesthesia.


Assessment Of A Hand Exoskeleton On Proximal And Distal Training In Virtual Environments For Robot Mediated Upper Extremity Rehabilitation, Kevin Abbruzzese Jan 2017

Assessment Of A Hand Exoskeleton On Proximal And Distal Training In Virtual Environments For Robot Mediated Upper Extremity Rehabilitation, Kevin Abbruzzese

Dissertations

Stroke is the leading cause of disability in the United States with approximately 800,000 cases per year. This cerebral vascular accident results in neurological impairments that reduce limb function and limit the daily independence of the individual. Evidence suggests that therapeutic interventions with repetitive motor training can aid in functional recovery of the paretic limb. Robotic rehabilitation may present an exercise intervention that can improve training and induce motor plasticity in individuals with stroke. An active (motorized) hand exoskeleton that provides support for wrist flexion/extension, abduction/adduction, pronation/supination, and finger pinch is integrated with a pre-existing 3-Degree of Freedom (DOF) haptic …


Structurofunctional Resting-State Networks Correlate With Motor Function In Chronic Stroke, Benjamin Kalinosky, Reivian B. Barillas, Brian D. Schmit Jan 2017

Structurofunctional Resting-State Networks Correlate With Motor Function In Chronic Stroke, Benjamin Kalinosky, Reivian B. Barillas, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

Purpose

Motor function and recovery after stroke likely rely directly on the residual anatomical connections in the brain and its resting-state functional connectivity. Both structural and functional properties of cortical networks after stroke are revealed using multimodal magnetic resonance imaging(MRI). Specifically, functional connectivity MRI (fcMRI) can extract functional networks of the brain at rest, while structural connectivity can be estimated from white matter fiber orientations measured with high angular-resolutiondiffusion imaging (HARDI). A model that marries these two techniques may be the key to understanding functional recovery after stroke. In this study, a novel set of voxel-level measures …


Engineering Synthetic Feedback To Promote Recovery Of Self-Feeding Skills In People With Sensory Deficits Due To Stroke, Alexis Krueger Oct 2016

Engineering Synthetic Feedback To Promote Recovery Of Self-Feeding Skills In People With Sensory Deficits Due To Stroke, Alexis Krueger

Master's Theses (2009 -)

Kinesthesia refers to sensations of limb position and movement, and deficits of upper limb kinesthetic feedback are common after stroke, impairing stroke survivors’ ability to perform the fundamental reaching and stabilization behaviors needed for daily functions like self-feeding. I attempt to mitigate the negative impact of post-stroke kinesthesia deficits by evaluating the utility of vibrotactile sensory substitution to restore closed-loop kinesthetic feedback of the upper limb. As a first step, this study evaluated performance in healthy individuals during fundamental reaching, stabilization, and tracking behaviors while using supplemental vibrotactile feedback encoding either limb state information or goal-aware error information. First, I …


Lesion Identification And The Effect Of Lesion On Motor Mapping After Stroke, Ruixi Zhou May 2016

Lesion Identification And The Effect Of Lesion On Motor Mapping After Stroke, Ruixi Zhou

McKelvey School of Engineering Theses & Dissertations

Stroke is the most common cause of long-term severe disability and the motor system that is most commonly affected in stroke. One of the mechanisms that underlies recovery of motor deficits is reorganization or remapping of functional representations around the motor cortex. This mechanism has been shown in monkeys, but results in human subjects have been variable. In this thesis, I used a database that includes longitudinal behavioral and multimodal imaging data in both stroke patients and healthy controls for two research projects. Firstly, I improved an automatic lesion segmentation method to aid in the identification of the location and …


Structural-Functional Brain Connectivity Underlying Integrative Sensorimotor Function After Stroke, Benjamin Thomas Kalinosky Apr 2016

Structural-Functional Brain Connectivity Underlying Integrative Sensorimotor Function After Stroke, Benjamin Thomas Kalinosky

Dissertations (1934 -)

In this dissertation research project, we demonstrated the relationship between the structural and functional connections across the brain in stroke survivors. We used this information to predict arm function in stroke survivors, suggesting that the tools developed through this research will be useful for prescribing individualized rehabilitation strategies in people after stroke. Current clinical methods for rehabilitating sensorimotor function after stroke are not based on the locus of injury in the brain. Instead, therapies are generalized, treating symptoms such as weakness and spasticity. This results in outcomes that are highly variable, with severity of impairment immediately following stroke as the …


Plasticity Of The Cortical Representation Of Finger Extensors Induced By Paired Associative Stimulation, Ian Anthony Gerard Lafond Jan 2016

Plasticity Of The Cortical Representation Of Finger Extensors Induced By Paired Associative Stimulation, Ian Anthony Gerard Lafond

Dissertations

This dissertation first explored associative plasticity of the human motor cortical representation with the use of noninvasive transcranial magnetic stimulation (TMS) paired with peripheral electrical stimulation. Paired Associative Stimulation (PAS) has grown in popularity because of its potential clinical applications. PAS techniques are used in combination with electromyography (EMG) measurements to study cortical excitability and features of hand movement. This work focuses on a cohesive approach to answer central questions about: the ideal mechanism to facilitate cortical plasticity via PAS, the interaction between the behavior performed and type of stimulation delivered to the targeted cortical network and the effects of …


An Investigation Of Kinetic Visual Biofeedback On Dynamic Stance Symmetry, Trisha J. Massenzo Jan 2016

An Investigation Of Kinetic Visual Biofeedback On Dynamic Stance Symmetry, Trisha J. Massenzo

Theses and Dissertations

The intent of the following research is to utilize task-specific, constraint-induced therapies and apply towards dynamic training for symmetrical balance. Modifications to an elliptical trainer were made to both measure weight distributions during dynamic stance as well as provide kinetic biofeedback through a man-machine interface. Following a review of the background, which includes research from several decades that are seminal to current studies, a design review is discussed to cover the design of the modified elliptical (Chapter 2).

An initial study was conducted in a healthy sample population in order to determine the best visual biofeedback representation by comparing different …


Effect Of Tendon Vibration On Hemiparetic Arm Stability In Unstable Workspaces, Megan O. Conrad, Bani Gadhoke, Robert A. Scheidt, Brian D. Schmit Dec 2015

Effect Of Tendon Vibration On Hemiparetic Arm Stability In Unstable Workspaces, Megan O. Conrad, Bani Gadhoke, Robert A. Scheidt, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

Sensory stimulation of wrist musculature can enhance stability in the proximal arm and may be a useful therapy aimed at improving arm control post-stroke. Specifically, our prior research indicates tendon vibration can enhance stability during point-to-point arm movements and in tracking tasks. The goal of the present study was to investigate the influence of forearm tendon vibration on endpoint stability, measured at the hand, immediately following forward arm movements in an unstable environment. Both proximal and distal workspaces were tested. Ten hemiparetic stroke subjects and 5 healthy controls made forward arm movements while grasping the handle of a two-joint robotic …


Increased Lower Limb Spasticity But Not Strength Or Function Following A Single-Dose Serotonin Reuptake Inhibitor In Chronic Stroke, Krishnaj Gourab, Brian D. Schmit, T. George Hornby Dec 2015

Increased Lower Limb Spasticity But Not Strength Or Function Following A Single-Dose Serotonin Reuptake Inhibitor In Chronic Stroke, Krishnaj Gourab, Brian D. Schmit, T. George Hornby

Biomedical Engineering Faculty Research and Publications

Objective: To investigate the effects of single doses of a selective serotonin reuptake inhibitor (SSRI) on lower limb voluntary and reflex function in individuals with chronic stroke.

Design: Double-blind, randomized, placebo-controlled crossover trial.

Setting: Outpatient research setting.

Participants: Individuals (N=10; 7 men; mean age ± SD, 57±10y) with poststroke hemiplegia of >1 year duration who completed all assessments.

Interventions: Patients were assessed before and 5 hours after single-dose, overencapsulated 10-mg doses of escitalopram (SSRI) or placebo, with 1 week between conditions.

Main Outcome Measures: Primary assessments included maximal ankle and knee isometric strength, and velocity-dependent (30°/s–120°/s) plantarflexor stretch reflexes under …


Using Swing Resistance And Assistance To Improve Gait Symmetry In Individuals Post-Stroke, Sheng-Che Yen, Brian D. Schmit, Ming Wu Aug 2015

Using Swing Resistance And Assistance To Improve Gait Symmetry In Individuals Post-Stroke, Sheng-Che Yen, Brian D. Schmit, Ming Wu

Biomedical Engineering Faculty Research and Publications

A major characteristic of hemiplegic gait observed in individuals post-stroke is spatial and temporal asymmetry, which may increase energy expenditure and the risk of falls. The purpose of this study was to examine the effects of swing resistance/assistance applied to the affected leg on gait symmetry in individuals post-stroke. We recruited 10 subjects with chronic stroke who demonstrated a shorter step length with their affected leg in comparison to the non-affected leg during walking. They participated in two test sessions for swing resistance and swing assistance, respectively. During the adaptation period, subjects counteracted the step length deviation caused by the …


A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt Mar 2015

A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt

Robert Scheidt

Background: Proprioception plays important roles in planning and control of limb posture and movement. The impact of proprioceptive deficits on motor function post-stroke has been difficult to elucidate due to limitations in current tests of arm proprioception. Common clinical tests only provide ordinal assessment of proprioceptive integrity (eg. intact, impaired or absent). We introduce a standardized, quantitative method for evaluating proprioception within the arm on a continuous, ratio scale. We demonstrate the approach, which is based on signal detection theory of sensory psychophysics, in two tasks used to characterize motor function after stroke. Methods: Hemiparetic stroke survivors and neurologically intact …


Motivating Rehabilitation By Distorting Reality, James L. Patton, Yejun Wei, Chris Scharver, Robert V. Kenyon, Robert A. Scheidt Mar 2015

Motivating Rehabilitation By Distorting Reality, James L. Patton, Yejun Wei, Chris Scharver, Robert V. Kenyon, Robert A. Scheidt

Robert Scheidt

We have found, through a series of recent experiments, encouraging evidence that the neuro-motor system is motivated to change motor patterns when exposed to visuo-motor tasks. We have also shown that the learning of these tasks can be heightened with forces and/or visual distortions that appropriately manipulate the error. This process does not require intense concentration and it is often considered a game. We describe the next generation of robotic large-workspace, three dimensional haptics/graphics systems for rehabilitation


Stroke-Related Effects On Maximal Dynamic Hip Flexor Fatigability And Functional Implications, Henry Kuhnen, Megan M. Rybar, Tanya Onushko, Ryan E. Doyel, Sandra K. Hunter, Brian D. Schmit, Allison Hyngstrom Mar 2015

Stroke-Related Effects On Maximal Dynamic Hip Flexor Fatigability And Functional Implications, Henry Kuhnen, Megan M. Rybar, Tanya Onushko, Ryan E. Doyel, Sandra K. Hunter, Brian D. Schmit, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Introduction: Stroke-related changes in maximal dynamic hip flexor muscle fatigability may be more relevant functionally than isometric hip flexor fatigability. Methods: Ten chronic stroke survivors performed 5 sets of 30 hip flexion maximal dynamic voluntary contractions (MDVC). A maximal isometric voluntary contraction (MIVC) was performed before and after completion of the dynamic contractions. Both the paretic and nonparetic legs were tested. Results: Reduction in hip flexion MDVC torque in the paretic leg (44.7%) was larger than the nonparetic leg (31.7%). The paretic leg had a larger reduction in rectus femoris EMG (28.9%) between the first and last …


Perception Of Lower Extremity Loads In Stroke Survivors, Virginia W. Chu, T. George Hornby, Brian D. Schmit Jan 2015

Perception Of Lower Extremity Loads In Stroke Survivors, Virginia W. Chu, T. George Hornby, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

Objective: This study aimed to improve our understanding of static and dynamic lower extremity sensory perception and the impact of sensory impairments on the control of walking in stroke survivors.

Methods: Using a custom, real-time unloading system, we tested load perception at heel strike, mid stance and push off in 10 stroke survivors and compared their performance to 10 age-matched and 5 young adult control subjects. Dynamic load perception was based on a judgment of which leg was bearing more load, which was altered on a step by step basis. We also examined lower extremity static load perception, coordination, proprioception, …


Role Of Sensation In Altered Phalanx Grip Force In Persons With Stroke, Leah R. Enders Dec 2014

Role Of Sensation In Altered Phalanx Grip Force In Persons With Stroke, Leah R. Enders

Theses and Dissertations

Many individuals experience hand impairment after stroke leading to decreased ability to perform daily living activities. Previous research studies have investigated how stroke survivors' pinch grip control differs from healthy individuals, even though many individuals can only grasp with power grip after stroke. Furthermore, many stroke survivors experience tactile sensory deficit in their paretic limb in addition to motor deficit. It is currently unknown how stroke induced tactile sensory deficit affects power grip force directional control, which is important in terms of preventing object slippage and power grip normal force generation. Additionally it is unknown if power grip could be …


A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt Apr 2014

A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Background: Proprioception plays important roles in planning and control of limb posture and movement. The impact of proprioceptive deficits on motor function post-stroke has been difficult to elucidate due to limitations in current tests of arm proprioception. Common clinical tests only provide ordinal assessment of proprioceptive integrity (eg. intact, impaired or absent). We introduce a standardized, quantitative method for evaluating proprioception within the arm on a continuous, ratio scale. We demonstrate the approach, which is based on signal detection theory of sensory psychophysics, in two tasks used to characterize motor function after stroke.

Methods: Hemiparetic stroke survivors and neurologically intact …