Electronic Sensing System for Bipolar sEMG Detection and Angular Measurement for the Characterization of Foot Drop Pathology

Objective: It is common that during medical consultancies, work, and time are spent to characterize physical pathologies; this can optimize recovery times and rehabilitation opportunities. This research work was to develop a portable and technological prototype that allowed to perform the bipolar surface electromyography (sEMG) detection for the Tibialis Anterior (TA) and Peroneus Longus (PL) muscles and angular displacement measurements of the ankle-foot joint for the characterization of Foot Drop (FD) pathology. Method: An electronic system was designed and developed around a Central Processing Unit (CPU) responsible for receiving the sensors measurements to then assemble data packets for storage and transmission. The bipolar sEMG detection is carried out through an analogous conditioning module consisting of instrumentation, filtering, and amplification stages. This unit allows for obtaining the raw, rectified, and envelope signal. The angular displacement measurement is accomplished with an IMU inertial measurement system. Results: A statistical analysis was achieved to validate the precision of the measurements regard to commercial instruments; likewise, a robust analysis was implemented both in the time domain and in the frequency domain for bipolar sEMG detection, to assess the energetic distribution of the TA and PL muscle contractions. Conclusions: The data collected and the experimental platform show the great potential that the electronic system has to measure physiological variables in real-time, affirming its operation and technical capabilities. Importance: By miniaturizing the size of the equipment, making it completely wireless and improving the processing capacity, the developed system opens a new viewpoint in the measurement of physiological variables for medical purposes and applications.