Citation

Lipsitz L, Lough M, Niemi JB, Travison T, Howlett H, Manor B. Arch. Phys. Med. Rehabil. 2014; 96(3): 432-439.

Affiliation

Hebrew SeniorLife (HSL) Institute for Aging Research, Boston MA; Beth Israel Deaconess Medical Center, Boston MA; Harvard Medical School, Boston MA.

Copyright

(Copyright © 2014, Elsevier Publishing)

DOI

10.1016/j.apmr.2014.10.004

PMID

25450133

Abstract

OBJECTIVE: The objective of this study was to test whether subsensory vibratory noise applied to the sole of the foot using a novel piezo-electric vibratory insole, can significantly improve sensation, enhance balance, and reduce gait variability in elderly people. We also aimed to determine the optimal level of vibratory noise , and whether the therapeutic effect would endure and the user's sensory threshold would remain constant during the course of a day.

DESIGN: A randomized single-blind crossover study of three subsensory noise stimulation levels on 3 separate days. SETTING: Balance and gait laboratory PARTICIPANTS: 12 healthy community-dwelling elderly volunteers aged 65 - 90 years who could feel the maximum insole vibration. INTERVENTION: A urethane foam insole with the piezo-electric actuators delivering subsensory vibratory noise stimulation to the soles of the feet. MAIN OUTCOME MEASURES: Balance, gait, and timed up-and-go tests.

RESULTS: The vibratory insoles significantly improved performance on the timed up-and-go test, reduced the area of postural sway, and reduced the temporal variability of walking at both 70% and 85% of the sensory threshold and throughout the course of a day. Vibratory sensation thresholds remained relatively stable within and across study days.

CONCLUSIONS: This study provides proof of concept that the application of the principle of stochastic resonance to the foot sole sensory system using a new low voltage piezoelectric technology can improve measures of balance and gait that are associated with falls. Effective vibratory noise amplitudes range from 70% to 85% of the sensory thresholds and can be set once daily.

Language: en