Numerical Simulation of Pulsed Electromagnetic Field (PEMF) Tissue Therapy

Pulsed Electromagnetic Field (PEMF) therapy involves the use of pulsed radiofrequency (rf) electromagnetic waves to treat a range of maladies from chronic wounds to fractured bones. This non-invasive therapy is applied using an external coil that is pulsed and generates a time-varying magnetic field within the treated tissue. This in turn induces a timevarying electric field and associated current flow in the tissue that stimulates a variety of biological processes from increased blood flow to an enhanced cellular function that collectively promotes healing of bones and tissue. In this paper, we demonstrate a 2D-axisymmetric computational model for predicting electromagnetic aspects of PEMF therapy. Specifically, the model predicts the generation and penetration of a coil-generated rf magnetic field, the induced electric field and current by taking into account the different tissue layers and their individual frequency-dependent electrical properties. In addition, we use the Pennes' bioheat equation to predict the temperature rise due to the current induced Joule heating throughout the treated tissue. The computational model provides a fundamental understanding of PEMF-tissue coupling and enables the rational design of novel PEMF medical devices.