A Wearable Vibrotactile Biofeedback System to Improve Spatiotemporal Gait Parameters of Individuals with Lower-Limb Amputation

Rafael Escamilla (1,2), Jan Andrysek (1,2)

  1. Institute of Biomaterials and Biomedical Engineering, University of Toronto

  2. Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital

Rationale: Individuals with lower-limb amputation (LLA) typically have reduced sensory-motor control, resulting in gait and balance deficits and diminished mobility function. Biofeedback (BFB) systems have the potential to improve overall prosthetic function and mobility by providing real-time biomechanical sensory feedback, using visual, auditory and haptic cues. 

Objective: To develop and evaluate a wearable vibrotactile BFB system for use as a clinical tool to normalize lower-limb loading duration in individuals with LLA.

Methods: A BFB system was developed to track selected gait parameters (i.e., percentage of stance-phase), based on measurements of spatiotemporal events (i.e., heel strike and toe-off). The study design involved six (N=6) healthy subjects and two (N=2) prosthetic users. All subjects were tested under three different conditions: i) No stimulation “NF”, ii) Single stimulation “S”, and iii) Multiple stimulation “M”, within a single 2-hour session. In total, 20 trials per participant. Each trial consisted of a 10 meters walking in straight line at self-selected speed, wearing the BFB system. Percentage of stance-phase was measured during each trial.

Results: A statistically significant difference (p<0.0001) was found, by a repeated measure of ANOVA, between trials, treatments and subjects, including within subjects interactions (i.e., trial*treatment, trial*subject, treatments*subjects, and trial*treatments*subjects). In addition, a statistically significant difference (p<0.0001) between NF and stimulation (S and M) was found by a mixed model and a post-hoc Tukey analysis. However, no statistically significant result was found when comparing against treatments (S Vs M).

Conclusion: Consequently, it is shown that this augmented training experience using the wearable vibrotactile BFB system (either with S or M stimulation) is sufficient to alter/improve gait performance (i.e., percentage of stance-phase) of able-bodied subjects and individuals with LLA.

Clinical EngineeringiARC