CALCULATIONS OF ELECTRIC FIELDS IN THE HUMAN KNEE PRODUCED BY A KNEE-THIGH ELECTRODE PAIR

Abstract

Calculations of the electric fields produced in the cartilage of the human knee by a knee-thigh electrode pair excited by a low-frequency voltage waveform are presented and discussed. The simulations were performed using a three-dimensional finite-difference frequency-domain technique based upon an equivalent circuit model for solving Maxwell's equations. The leg model used in these calculation was obtained from the anatomically segmented human-body model of Gandhi. The calculated average electric fields within the medial and lateral cartilage were found to be 2.92 V/m and 2.51 V/m respectively for a voltage excitation of one volt at a frequency of 1 kHz applied between the electrodes. A special truncation technique, which incorporates information from a physically larger coarse model in the excitation of a finer subsection of the model, was utilized to obtain higher resolution results in the region of interest.