Effect of novel training to normalize altered finger force direction post-stroke: study protocol for a double-blind randomized controlled trial.

BACKGROUND: Functional task performance requires proper control of both movement and force generation in three-dimensional space, especially for the hand. Control of force in three dimensions, however, is not explicitly treated in current physical rehabilitation. To address this gap in treatment, we have developed a tool to provide visual feedback on three-dimensional finger force. Our objective is to examine the effectiveness of training with this tool to restore hand function in stroke survivors. METHODS: Double-blind randomized controlled trial. All participants undergo 18 1-h training sessions to practice generating volitional finger force of various target directions and magnitudes. The experimental group receives feedback on both force direction and magnitude, while the control group receives feedback on force magnitude only. The primary outcome is hand function as measured by the Action Research Arm Test. Other outcomes include the Box and Block Test, Stroke Impact Scale, ability to direct finger force, muscle activation pattern, and qualitative interviews. DISCUSSION: The protocol for this clinical trial is described in detail. The results of this study will reveal whether explicit training of finger force direction in stroke survivors leads to improved motor control of the hand. This study will also improve the understanding of neuromuscular mechanisms underlying the recovery of hand function. TRIAL REGISTRATION: ClinicalTrials.gov NCT03995069 . Registered on June 21, 2019.

Concomitant sensory stimulation during therapy to enhance hand functional recovery post stroke.

BACKGROUND: Post-stroke hand impairment is prevalent and persistent even after a full course of rehabilitation. Hand diminishes stroke survivors' abilities for activities of daily living and independence. One way to improve treatment efficacy is to augment therapy with peripheral sensory stimulation. Recently, a novel sensory stimulation, TheraBracelet, has been developed in which imperceptible vibration is applied during task practice through a wrist-worn device. The objective of this trial is to determine if combining TheraBracelet with hand task practice is superior to hand task practice alone. METHODS: A double-blind randomized controlled trial will be used. Chronic stroke survivors will undergo a standardized hand task practice therapy program (3 days/week for 6 weeks) while wearing a device on the paretic wrist. The device will deliver TheraBracelet vibration for the treatment group and no vibration for the control group. The primary outcome is hand function measured by the Wolf Motor Function Test. Other outcomes include the Box and Block Test, Action Research Arm Test, upper extremity use in daily living, biomechanical measure of the sensorimotor grip control, and EEG-based neural communication. DISCUSSION: This research will determine clinical utility of TheraBracelet to guide future translation. The TheraBracelet stimulation is delivered via a wrist-worn device, does not interfere with hand motion, and can be easily integrated into clinical practice. Enhancing hand function should substantially increase stroke survivors' independence and quality of life and reduce caregiver burden. TRIAL REGISTRATION: NCT04569123 . Registered on September 29, 2020.

Effect of Sensory Impairment on Hand Functional Improvement with Therapy and Sensory Stimulation.

Sensory impairment may impact individual stroke survivors' motor recovery as well as their response to peripheral sensory stimulation treatment. The objective of this study was to determine the effect of sensory impairment level of individual stroke survivors on motor improvement with therapy and peripheral sensory stimulation. A secondary analysis of a pilot triple-blind randomized controlled trial was used. Twelve chronic stroke survivors were randomly assigned to the treatment group receiving peripheral sensory stimulation or the control group receiving no stimulation during 2-week hand task practice therapy. Sensory impairment level was quantified as the pre-intervention sensory threshold. Motor improvement was assessed as change in the Box and Block Test score from pre- to post-intervention. The association between sensory impairment level and motor improvement was examined using a regression analysis, accounting for groups. This study found that participants with better sensation (i.e., with lower sensory threshold) had better motor improvement than patients with worse sensation (i.e., with higher sensory threshold). Sensory impairment level did not alter the effect of peripheral sensory stimulation. These findings suggest that the level of sensory impairment may predict recovery potentials and direct rehabilitation treatment for stroke survivors.