EMG Controlled Rollover Support System for Bone Cancer Metastasis Patient (1^st report) EMG Signal Analysis in Rollover Movement as an Input Signal

Abstract

More than seven million people around the world die of cancer each year, some of whom suffer from pain caused by bone metastasis. In their final stages of life, the pain is such that they cannot even roll over, one of the activities of daily life. With this in mind, in this research we aimed to develop a new corset for patients with cancer bone metastasis, not to feel pain which is caused by the trunk twisting motion when they conduct their rollovers in terminal care. Specifically, the surface EMG signal, which is the input signal of the system to recognize the start of the rollover movement, is delivered in this paper. At first, the rollover movement is categorized into Upper Limb Precedence Type, Lower Limb Precedence Type and Lower Limb Flexion Type. After that, the activities of four muscles (external abdominal oblique, internal abdominal oblique, rectus abdominis and erectore spinae) affecting trunk movement were monitored during the process of each rolling over type. Following an EMG experiment using the Average Reflected Value (ARV) as an evaluation index with three young subjects, the internal abdominal oblique (IO) muscle was seen to be active before the start or in the early stages of rollover motion, although IO was relatively prevalent in previous work. Moreover, the same EMG experiment with a elderly woman showed the activity of the lower part of the IO muscle before the start or at the early stage of the rollover movement. Hence, the surface EMG signal of the lower part of the IO muscle was selected as the input signal of the equipment to recognize the start of the rollover movement.