Management of musculoskeletal shoulder and neck pain through ergonomic intervention: a pre-post design analysis in hand screen printing industry

Abstract

Hand screen printing process (HSP) is a highly labour intensive work involving repetitive and awkward motion without proper ergonomic tools. The main purpose of this study is to modify the design of the traditionally employed wooden squeegee and evaluate its effect on muscle activity during HSP process. Twenty hand screen printing industry workers participated in the study and printed the design on 30-metre length cloth using both traditional and modified squeegee. Surface electromyography (SEMG) is used to record the muscle activity of sternocleidomastoid (SCM), upper trapezius (bilateral) and infraspinatus (bilateral) muscles during HSP process. One way ANOVA and chi square test is performed using SPSS version 21.0 and the result showed that the data obtained using both traditional and modified squeegee are statistically significant. Introducing modified squeegee in HSP process reduces muscle activity of sternocleidomastoid (SCM), upper trapezius (bilateral) and infraspinatus (bilateral) muscles during HSP process thereby reduces the risk of neck and shoulder injuries.