There is no long-term effect on the nerve: the geko® device has been used over periods of several weeks to treat chronic conditions and no issues of overstimulation have been reported in subsequent publications. The use of the geko® device has been the subject of numerous studies and there have been no reports of any long-term problems with the stimulation level. The amount of electrical charge required by the geko® device to achieve stimulation of the common peroneal nerve is much less than other electrical stimulators because of the unique way in which the geko® device works. The electrical charge is ‘balanced’, that is – there is zero net charge delivered to the patient, this is achieved by having a series of small pulses following the stimulation pulse of opposite polarity which balances the charge in the stimulation pulse without stimulating the nerve further. This prevents electrochemical changes in the skin occurring.
If ‘over stimulation’ refers to the strength of the contraction, there is a natural limit to the strength of the muscle contraction that the geko® device can achieve. The stimulation level is controlled by the pulse width (that is the length of time that the stimulation pulse lasts for). The maximum 560 micro-second pulse width will only cause a single short contraction of the calf muscles controlled by the common peroneal nerve. Longer contractions require repeated stimulation pulses.