Variations in the electrical conductance of the intact skin of human beings has been recognized for many years. Particularly high conductance sites have been associated with acupuncture points as well as with trigger points in myofascial pain syndromes. However, the realization that this change in electrical skin conductance was related to the presence of subcutaneous nerves was only made recently by the inventor, and represents a unique finding. Although the measurement of transcutaneous: electrical conductivity has been used for other purposes, it has never before been shown to reveal the position of neural tissue.
The present non-invasive-peripheral nerve mapping device and method may be used to indicate the site of nerve injury or nerve transection. Sudden loss of transcutaneous electrical hyperconductivity along the course of a peripheral nerve is indicative of interruption of the nerve fiber whereas a focal increase in the transcutaneous electrical hyperconductivity along the course of a peripheral nerve is evidence of a site of nerve injury without actual transection.