Electronic implementation of a PWM electrical nerve stimulation system for medical treatment of acute and chronic pains

Abstract

In this paper we will implement a transcutaneous electrical nerve stimulation (TENS) designed for medical applications in order to reduce acute and chronic pains. This procedure uses electrical currents pulses applied on the skin area via electrodes. Two kinds of stimulation are adopted: the peripheral nerve stimulation (PNS) and the spinal cord stimulation (SCS). In either, a small pulse generator sends electrical pulses to the nerves (in PNS stimulation) or to the spinal cord (SCS stimulation). Previous studies on TENS technique showed that the obtained results are not very satisfactory and depend on the patient’s state, condition, age, and stimulation parameters. In order to optimize the conditions and parameters stimulation during treatments, we present in this paper a new strategy called pulse width modulation stimulation (PWM-TENS) based on a parametric computing of frequency, current intensity, pulse duration of stimuli. To implement our approach, we used an embedded platform under Arduino-Uno with five several programs depending on the pain category and according to international medical standards and specifications. The first tests on 15 volunteer patients showed satisfaction ratio (EVA) after 5–12 days and a pain reduction between 80 and 20 after 1 month of stimulation. This result is important because it prolongs the analgesic effect and reduces therapeutic rehabilitation period. The medical aspect of the subject is to have a medical tool that allows objective evaluations for short and medium periods of pain treatments with dynamic evaluation metrics.