TheraBracelet Stimulation During Task-Practice Therapy to Improve Upper Extremity Function After Stroke: A Pilot Randomized Controlled Study

Abstract

Background: Peripheral sensory stimulation has been used in conjunction with upper extremity movement therapy to increase therapy-induced motor gains in patients with stroke. The limitation is that existing sensory stimulation methods typically interfere with natural hand tasks and thus are administered prior to therapy, requiring patients' time commitment. To address this limitation, we developed TheraBracelet. This novel stimulation method provides subthreshold (ie, imperceptible) vibratory stimulation to the wrist and can be used during hand tasks/therapy without interfering with natural hand tasks.

Objective: The objective was to determine the feasibility of using TheraBracelet during therapy to augment motor recovery after stroke.

Design: The design was a triple-blinded pilot randomized controlled trial.

Methods: Twelve chronic stroke survivors were assigned to the treatment or control group. All participants completed 2-hour task practice therapy sessions thrice weekly for 2 weeks. Both groups wore a small vibrator on the paretic wrist, which was turned on to provide TheraBracelet stimulation for the treatment group and turned off for the control group to provide sham stimulation. Outcome measures (Box and Block Test [BBT] and Wolf Motor Function Test [WMFT]) were obtained at baseline, 6 days after therapy, and at follow-up 19 days after therapy.

Results: The intervention was feasible with no adverse events. The treatment group significantly improved their BBT scores after therapy and at follow-up compared with baseline, whereas the control group did not. For WMFT, the group × time interaction was short of achieving significance. Large effect sizes were obtained (BBT d = 1.43, WMFT d = 0.87). No indication of desensitization to TheraBracelet stimulation was observed.

Limitations: The limitation was a small sample size.

Conclusions: TheraBracelet could be a promising therapy adjuvant for upper extremity recovery after stroke.

Trial registration: ClinicalTrials.gov NCT02675764.

© 2019 American Physical Therapy Association.

Figures

Figure 1.

A vibrator was fixed to the paretic wrist and delivered subthreshold random-frequency vibration (TheraBracelet stimulation) for the treatment group and no vibration (sham) for the control group during task-practice therapy addressing hand object manipulation, such as opening a lock (A) and applying toothpaste (B).

Figure 2.

A custom-designed MATLAB program determined the participant's sensory threshold, randomly assigned the participant to a group (either treatment or control), and delivered either the treatment vibration or zero vibration depending on group assignment during therapy, to enable blinding of researchers.

Figure 3.

CONSORT flow diagram.

Figure 4.

Change in the wrist sensory threshold across therapy sessions (means and error bars showing standard errors are shown).

Figure 5.

Changes in outcome measures. Mean change in (A) Box and Block Test (BBT) score and (B) reduction in movement time (s) in log for Wolf Motor Function Test (WMFT) with error bars showing standard error for each group and for each evaluation time (baseline, 6 d post-2-wk therapy [“Post”], and 19 d post-2-wk therapy [“Followup”]). Individual participants’ changes are also shown for BBT (C) and log of WMFT time (D).