Active clinical trials for "Paresis"

Texas Biomedical Device Center at UT Dallas has developed an innovative strategy to enhance recovery of motor and sensory function after neurological injury termed targeted plasticity therapy (TPT). This technique uses brief pulses of vagus nerve stimulation to engage pro-plasticity neuromodulatory circuits during rehabilitation exercises. Recovery is associated with neural plasticity in spared motor networks in the brain and spinal cord. Moreover, an early feasibility study and an independent, double-blind, placebo-controlled study in chronic stroke participants indicate that VNS is safe in participants with upper limb deficits, and yields a clinically-significant three-fold increase in neural connections during rehabilitation exercises. Given the track record of safety and potential for VNS to enhance recovery of upper limb motor function in spinal cord injured individuals, the purpose of this double blind randomized placebo controlled optional open-label extension study is to assess the safety of using a new device to deliver vagus nerve stimulation to reduce symptom severity in participants with SCI. Additionally, the study will assess the prospective benefit of the system and garner an initial estimate of efficacy for a subsequent trial. Participants may undergo additional sessions of training with VNS.

The purpose of this research is to learn about practice conditions that may benefit stroke survivors when learning to use their more affected arm to perform a task. Participants will be randomized into two groups. Experimental and control groups will differ by one practice variable that will not be disclosed until completion of testing procedures. Participants will practice a motor task using both their more and less affected arms for two consecutive days. A Pre-Test will be administered on Day 1 before the training begins. Immediate Transfer of Learning will be administered on Day 2 after the completion of training. Delayed (24-hour) Retention and Transfer Tests will be administered on Day 3.

The study is focused on the evaluation of the feasibility, usability, acceptability, tolerance, functional impact and organizational impact of the use of a wearable prehension neuroprosthesis (innovative medical device) at home, with triggering methods specifically adapted to a population of hemiparetic post-stroke subjects. The main objective is to describe the overall therapeutic compliance represented by the number of uses of the neuroprosthesis in real-life situations.

It is unclear why humans typically swing their arms during gait. To date, the debate on how to arm swing comes about (i.e. whether it is caused by accelerations of the shoulder girdle or muscular activity) is still going on. There needs to be consensus on whether the arm swing is actively controlled or merely passive and on why humans swing their arms during walking (i.e. what the purpose of arm swing is, if any). Suggested reasons include minimising energy consumption, optimising stability, and optimising neural control. Pathologies such as hemiplegia after stroke, Parkinson's disease, Cerebral Palsy, Spinal Cord Injury, and Multiple Sclerosis may directly affect arm swing during gait. Emerging evidence indicates that including arm movements in gait rehabilitation may be beneficial in restoring interlimb coordination and decreasing energy expenditure. This project hypothesises that the arms swing, at least at low and intermediate walking speeds, reflects the body's Center of Mass (CoM) accelerations. Arm swing may thus depend mainly upon the system's intrinsic mechanical properties (e.g., gravity and inertia). In this perspective, the CoM is seen as moving relative to the upper limbs rather than the other way around. The contribution of major lower limb joints, in terms of power injected into the body motion, will be simultaneously explored. The study aims to investigate the mechanism and functions of arm swinging during walking on a force treadmill. To simulate asymmetric walking, healthy subjects will be asked to walk with a toes-up orthosis to induce claudication and asymmetry in ankle power. In this way, it will be possible to highlight the correlation among arm swinging, ankle power, and the acceleration of the CoM in a 3D framework. In addition, subjects affected by unilateral motor impairments will be asked to walk on the force treadmill to test the experimental model and highlight significant differences in the kinematic parameters of the upper limbs. The question of whether arm swing is actively controlled or merely passive and the relationship between arm swinging and the total mechanical energy of the CoM will be faced. Asymmetric oscillations of the upper limb will be related to dynamic asymmetries of the COM motion, and of the motion of lower limbs. In addition, cause-effect relationships will be hypothesized. Finally, the dynamic correlates of upper limb oscillations will make the clinical observation an interpretable clinical sign applicable to rehabilitation medicine. Results from the present study will also foster the identification of practical rehabilitation exercises on gait asymmetries in many human nervous diseases.

Stroke survivors experience motor deficits, weak voluntary muscle activations, and low weight-bearing capacity that impair ambulation. Restoring motor function is a priority for people post-stroke, whose gait patterns are slow, and metabolically inefficient. The role of the ankle is crucial for locomotion because it stores mechanical energy throughout the stance phase, leading to a large activation of plantarflexor muscles during push-off for propulsion. After a stroke, paretic plantarflexors undergo changes in their mechanics and activation patterns that yield diminished ankle power, propulsion, and gait speed. Recovery of lost plantarflexor function can increase propulsion and mitigate unnatural gait compensations that occur during hemiparetic walking. In the stance phase, dorsiflexion is imposed at the ankle and the plantarflexors are loaded, which results in excitation of group Ia and II afferents, and group Ib afferents. Load sensing Ib afferents are active in mid-late stance, and through spinal excitatory pathways, reinforces the activation of plantarflexors and propulsive force generation at the ankle. Targeting the excitability of the load sensitive Ib excitatory pathway, propulsive soleus activity and resulting force generation (and thereby gait speed) can be improved after stroke. The long-term research goal is to develop a novel hybrid gait paradigm integrating operant conditioning and powered wearable devices to advance neuro-behavioral training and enhance locomotor ability after stroke. The overall objectives are to 1) modulate the soleus muscle loading response within the stance phase, and 2) develop a dynamic protocol to operantly condition the soleus response in stroke survivors. The central hypothesis is that enhancing the soleus loading response in mid-late stance phase through operant up-conditioning can increase plantarflexor power and forward propulsion after stroke. In working towards attaining the research objective and testing the central hypothesis, the objective of this pilot study is to modulate the soleus loading response in the stance phase during treadmill walking. The specific aims in this study are to 1) apply ankle perturbations in mid-late stance phase combining a control algorithm and a powered device to characterize the changes in soleus EMG between perturbed and unperturbed (i.e., when no perturbations are applied) step cycles in 15 able-bodied individuals; and 2) determine the feasibility of the wearable ankle device and its algorithm in 5 participants with hemiparesis and gait deficits due to a stroke. The testing of the device and its algorithm will provide foundational evidence to adjust the soleus stimuli continuously and reliably, and develop the new walking operant conditioning protocol for stroke survivors. An expected outcome in this pilot is to lay the groundwork to develop the soleus up-conditioning protocol as a potential strategy to improve paretic leg function. If successfully developed, this new protocol proposed in a subsequent study will be the first neurobehavioral training method that targets spinal load-sensitive pathways to improve ankle plantarflexor power and forward propulsion after stroke.

The primary objective of this study is to tailor and test implementation strategies to support the adoption of two upper extremity motor outcome measures for stroke: the Fugl-Meyer Assessment and the Action Research Arm Test. The study's interdisciplinary team will address this objective through the following specific aims: (a) Tailor a package of implementation strategies (referred to as I-STROM-Implementation STRategies for Outcome Measurement) to promote outcome measure use across the care continuum, (b) Determine the effectiveness of I-STROM on outcome measure adoption and (c) Evaluate the appropriateness, acceptability, and feasibility of I-STROM in rehabilitation settings across the country. The mixed-methods study design is informed by implementation science methodologies, and the tailoring of I-STROM will be guided by input from stakeholders, including occupational therapy practitioners and administrators. The investigators will collect robust quantitative and qualitative data by means of retrospective chart reviews, electronic surveys, and stakeholder focus groups. This study, "Strategies to Promote the Implementation of Outcome Measures in Stroke Rehabilitation," will address core barriers to outcome measure use through a package of implementation strategies, thus laying the groundwork for I-STROM scale-up in health systems nationwide.

Objective: The goal of this study is to implement and test a neuro-mechanical gait assist (NMGA) device to correct walking characterized by muscle weakness, incoordination or excessive tone in Veterans with hemiparesis after stroke that adversely affects their ability to walk, exercise, perform activities of daily living, and participate fully in personal, professional and social roles. Research Plan: A prototype NMGA device will be used to develop a finite state controller (FSC) to coordinate each user's volitional effort with surface muscle stimulation and motorized knee assistance as needed. Brace mounted sensors will be used to develop a gait event detector (GED) which will serve the FSC to advance through the phases of gait or stair climbing. In addition, a rule-base intent detection algorithm will be developed using brace mounted sensors and user interface input to select among various functions including walking, stairs climbing, sit-to-stand and stand-to-sit maneuvers. The FSC controller tuning and intent algorithm development and evaluation will be on pilot subjects with difficulty walking after stroke. Outcome measures during development will provide specifications for a new prototype NMGA design which will be evaluated on pilot subjects to test the hypothesis that the NMGA improves walking speed, distance and energy consumption of walking. These baseline data and device will be used to design a follow-up clinical trial to measure orthotic impact of NMGA on mobility in activities of daily living at home and community. Methodology: After meeting inclusion criteria, pilot subjects will undergo baseline gait evaluation with EMG activities of knee flexors and extensors, ankle plantar and dorsiflexors and isokinetic knee strength and passive resistance. They will be fitted with a NMGA combining a knee-ankle-foot-orthosis with a motorized knee joint and surface neuromuscular stimulation of plantar- and dorsi- flexors, vasti and rectus femoris. Brace mounted sensor data will be used for gait event detector (GED) algorithm development and evaluation. The GED will serve the FSC to proceed through phases of gait based on supervisory rule-based user intent recognition algorithm detected by brace mounted sensors and user input interface. The FSC will coordinate feed-forward control of tuned stimulation patterns and closed-loop controlled knee power assist as needed to control foot clearance during swing and stability of the knee during stance. Based on data attained during controller development and evaluation, a new prototype NMGA will be design, constructed and evaluated on pilot subjects to test the hypothesis that a NMGA device improves safety and stability, increases walking speed and distance and minimizes user effort. Clinical Significance: The anticipated outcome is improved gait stability with improved swing knee flexion, thus, increasing the safety and preventing injurious falls of ambulatory individuals with hemiplegia due to stroke found in large and ever-increasing numbers in the aging Veteran population. Correcting gait should lead to improved quality of life and participation.

This study is designed to further develop and test the hardware and software components of the MyHand device based on user feedback and results from our pilot study. The goal is to refine the device so that is more effective and easier for stroke patients to use to increase their hand function.

Texas Biomedical Device Center (TxBDC) has developed an innovative strategy to enhance recovery of motor and sensory function after neurological injury termed targeted plasticity therapy (TPT). This technique uses brief pulses of vagus nerve stimulation to engage pro-plasticity neuromodulatory circuits during rehabilitation exercises. Preclinical findings demonstrate that VNS paired with rehabilitative training enhances recovery in multiple models of neurological injury, including stroke, spinal cord injury, intracerebral hemorrhage, and traumatic brain injury. Recovery is associated with neural plasticity in spared motor networks in the brain and spinal cord. Moreover, two initial studies and a recently completed Phase 3 clinical trial using a commercially available device demonstrates that paired VNS with rehabilitation is safe and improves motor recovery after stroke. The purpose of this study is to extend these findings and evaluate whether VNS delivered with the new device paired with rehabilitation represents a safe and feasible strategy to improve recovery of motor and sensory function in participants with stroke.

Vagus nerve stimulation (VNS) activates neural pathways leading to the release of chemicals that promote plasticity and learning. Previous work has shown that the auricular branch of the vagus nerve innervates landmarks on the external ear. Work from the PI's laboratory has shown that electrical current applied to the external ear activates neural pathways implicated in the therapeutic effects of VNS. The broad objective of this project is to better understand physiological mechanisms that are modulated by auricular stimulation and its potential to enhance motor learning.