EMG Based Clinical Evaluation of an Unpowered Exoskeleton Device

Abstract

This paper reports a clinical study to characterize reduction in load on the major muscles of the back by use of an unpowered, lightweight, protective and therapeutic exoskeleton device named JaipurBelt that supports the spine and waist. Seventy nine subjects underwent Institutional Ethical Committee approved clinical trial at Santokba Durlabhji Memorial Hospital (SDMH), Jaipur, India. The protocols used for this study incorporate without device without load (WOJBWOL), without device with load (WOJBWL), with device without load at a medium level of support (WJBMidWOL), with device with load at a medium level of support (WJBMidWL), with device with load at a maximum level of support (WJBMaxWL). The EMG was recorded from six major back muscles. The result showed that, average reduction of muscle activity in all six muscles for Stoop Bending Up (SBU) is about 7.62%, and for Stoop Bending Down (SBD) is about 12.19% in without load condition. In with load condition and maximum level of support (WJBMaxWL), the overall maximum reduction of muscle activity was 80.97% for Ninth Thoracic Vertebra of Erector Spine (EST9), 44.39%. for Fourth Lumbar Vertebra of Erector Spine (ESL4), 24.62% for Multifidus (MF), 10.18% for Quadratus Lumborum (QL), 37.54% for Gluteus maximus (GM), 40.23% for Rectus Femoris (RF). In this clinical study, with the use of this unpowered exoskeleton device, it was found that there is a substantial reduction in muscle force requirements for load lifting, frequent bending ups, bending down and stooping activities by reducing the load from back and abdominal muscles. Thus, use of this device can potentially helps in reducing the risk of lower back disorders, fatigue, musculoskeletal problems, spinal disorders like slip disc and associated pain. This study was conducted after registration with Central trial register of India (CTRI registration number CTRI/2017/01/007649dtd 16/01/2017).