INTERNATIONAL JOURNAL OF RESEARCH IN AERONAUTICAL AND MECHANICAL ENGINEERING ISSN (ONLINE): 2321-3051 Vol.3 Issue.2, February 2015. Pgs: 10-17 Santosh Kumar, M. Muralidhar 10 IMPACT OF AGE ON POTENTIAL CTS SYMPTOMS AMONGST SHOCKER MANUFACTURING ASSEMBLY LINE WORKERS Santosh Kumar 1 , M. Muralidhar 2* Department of Mechanical Engineering, North Eastern Regional Institute of Science and Technology, Itanagar-791109, Arunachal Pradesh, India E-mail addresses: kumarsantoshchaurasia@gmail.com, mm@nerist.ac.in * Author Correspondence: Telephone: +91 360 2257401, Fax Number: +91 360 2258533, Email address: mm@nerist.ac.in Abstract In this communication an attempt has been made to examine the impact of age on potential Carpal Tunnel Syndrome (CTS) symptoms amongst shocker manufacturing assembly line workers in actual industrial environment through questionnaire and physical tests. Chi-square test and Surface electromyography (sEMG) signal values have been used for statistical data analysis. The chi-square test result reveals that probability of having CTS symptoms is more amongst workers beyond 35 years of age. Data indicates that 61.76% workers beyond 35 years of age whereas 25% of the workers having age less than 35 years of age are CTS symptoms sufferers. The sEMG signal analysis result reveals that the lesser muscle activity values (EMG-RMS values) indicate the contribution of CTS symptom in shocker assembly line workers. Keywords: Carpal tunnel syndrome, age, surface electromyography, abductor pollicis brevis, assembly line. 1. Introduction Carpal Tunnel Syndrome (CTS), a type of Repetitive Strain Injury (RSI) is the most commonly work related musculoskeletal disorder (WMSD) that can lead to temporary as well as permanent disabilities. WMSD is a common problem of medical health in working population. WMSDs can cause pain or numbness, lost work time, and an increase in worker’s compensation costs. Examples of WMSDs include back strain, shoulder tendonitis, and CTS (Patry et al., 1998, Fagarasanu & Kumar, 2003). CTS is brought on by over-worked, over- strained muscles of arms and hands, resulting in a loss of nerve conductivity, possibly leading to muscle strength problems (Kate, 1995). The detection, amplification and recording of changes in skin voltage produced by underlying skeletal muscle contraction are called electromyography. The recording obtained is called Electromyogram. The Abductor Pollicis Brevis (APB) is a member of the thenar muscles and is often affected by muscle antropy associated with CTS (Kulick, 1986, Mac-Dermid & Wessel, 2004, Marina et al., 2007). Although many clinical and biomechanical studies address CTS, the electrophysiological properties of the APB muscle are still not well understood (Bland, 2007, Liu et al., 2000, Nobuta et al., 2005, Olmo et al., 2000). EMG signal is a biomedical signal that measures electrical currents generated in muscles during its contraction representing neuromuscular activities. The nervous system always controls the muscle activity (contraction/relaxation). Hence, the EMG signal is a complicated signal, which is controlled by the nervous system and is dependent on the anatomical and physiological properties of muscles (Reaz et al., 2000). EMG is