Effects of Low Threshold Electrical Noise on Improving Balance Function

Objective. This study was conducted to investigate the effect of subsensory stimulation using commonly used micro current device on static and dynamic balance function in elderly subjects without known neurological disorders. Background. Stochastic resonance stimulation, which uses subsensory vibratorary or electrical noise applied to the skin to enhance somatosensory inputs, has proven to be useful in enhancing balance in the elderly, patients post stroke and patients with chronic ankle instability. Instrumentation used in the past was specifically designed for research purposes and not available for clinical practice. Method. This was a single group, random order, test-retest exploratory study. Subjects underwent testing with and without micro-current electrical stimulation to the ankles. Balance was tested using single/double leg stance with eyes open/closed; tandem stance with eyes open/closed; functional reach; anterior-posterior and medial-lateral translation on center of pressure and latency on step excursion test. Results. Fifteen subjects ages 65-87 were tested. The micro-current electrical stimulation, as compared to no stimulation, increased time on tandem stance with eyes closed from 2.85 sec. to 6.09 sec. (p = .005). No other balance test results were significantly different between the two testing conditions. Conclusion. The statistically significant improvement in tandem stance may be indicative of the positive effect of micro-current electrical stimulation on stance without visual feedback. The microcurrent appeared to provide stimulation in tandem stance compensating for lack of visual input when balance was challenged. This may have functional implications in patients with balance deficits when challenged by situations requiring a narrow base of support and could be implemented in most clinics that have commonly available micro-current stimulators. The actual physiological and long term effects warrant further investigation. Grants. This study was partially funded by a Florida Physical Therapy Association grant.