Evaluation of loads imposed on muscles and joints by repeated vacuum cleaning works for estimation of a potentiality of musculo-skeletal disorder occurrence

The excessive accumulation of physical burden is known widely as one of the main factors underlying musculoskeletal disorders in the working population. The current study was performed to evaluate the loads imposed on the muscles and joints by excessive accumulation of physical burdens for the estimation of a potentiality of musculoskeletal disorder occurrence, particularly in vacuum cleaning works, the motions most commonly performed both at home and in industry. A survey, rapid entire body assessment, and experimental/ virtual three-dimensional motion analysis were performed. The results showed that latissimus dorsi and trapezius muscle strengths and elbow and shoulder joint moments were generally higher than other muscle strengths and joint moments generated during cleaning works. In addition, motions required cleaning in corners and in hard-to-reach areas generally required more muscle strengths and joint moments than other motions. These findings may be used in improvement of vacuum cleaner (a device to clean up dust and dirt usually from floors) design reducing a potentiality of musculoskeletal disorder occurrence due to repeated cleaning works, through consideration of a methodology capable of decreasing the loads imposed on the muscles and joints by repeated cleaning works. The findings can be also expanded to improvement of working environments in which pushing and pulling works (cleaning works mainly included pushing and pulling motions) frequently occur, to reduce a potentiality of musculoskeletal disorder occurrence due to pushing and pulling works.