ROMeasure

Abstract

Range Of Motion (ROM) of joints is a key biomarker in assessing the osteokinematics of muskuloskeletal system. Goniometry of ROM is effected by orthopaedists through manual measurement using medical grade goniometers. Such measurement requires personal presence of a medical expert especially in passive goniometry. For a digital estimation of ROM of shoulder and elbow joints, smart wearables embedded with inertial sensors have been used. Although they cover a wide variety of ROM measurements, but fail for measurements made in certain planes, and require sensor specific calibration. Through this work, we aim to demonstrate a calibration-free solution for ROM estimation of shoulder and elbow joints, 'ROMeasure' which can work in any random plane of measurement with a high accuracy even at extremely slow speed of rotation greatly enhancing its practicality in a medical scenario. The demonstration includes a user wearing a smartwatch, and rotating elbow/shoulder joints. Graphs for real-time angle and rotation speed are displayed on a computer screen in real time and at the end of session, final range of motion is calculated. We believe that such a setup can be extrememly useful in a tele-health scenario, and owing to the pervasiveness of smart devices today, it can prove to be a highly convenient yet accurate solution for self-assessment. Our system has been observed to incur MAE of less than 5 degrees in meticulous experimentation performed on different subjects in multiple planes of rotation, even at a rotational speed of under 10 degrees per second.