Optimal current model from surface electrodes

Transcutaneous electrical neuromuscular stimulation (TENS) is finding increasing applicability. A new therapy using subthreshold TENS promotes growth and neuron sprouting in the target muscle. However, optimal current flow for effective use in such therapy has not been characterized. Previous models of the current distribution in long strip electrodes were one dimensional. This does not represent the dynamics accurately, especially in the smaller electrodes typically used in subthreshold TENS. In this investigation the current density flowing out of the electrode is modeled as a two dimensional surface. Together with the effects of skin, subcutaneous fat, muscle atrophy, and extracellular fluid, this model leads to a determination of optimal current flow from a stimulator