RELATIONSHIP BETWEEN LUMBAR DISC INJURY AND MANUAL LIFTING - A FINITE ELEMENT MODEL STUDY

摘要

Back pain has been described as one of the most common and significant musculoskeletal problems in the United States leading to substantial amounts of morbidity, disability and economic loss. Among people under 45 years of age, low back disorders (LBDs) are the leading cause of activity limitation and affects up to 47% of workers with physically demanding jobs. Low back disorders are associated with occupational lifting. Retrospective studies of industrial injuries have identified manual material handling (MMH) as the most common cause of LBD. Disc degeneration has also been associated with physical work. Thus, loading due to lifting and manual material handling is believed to be a significant factor in the development of occupationally related LBDs. While studies such as those mentioned above shed light on the relationship between lifting and LBD, our knowledge of the exposure-injury relationship is not well defined. Because this relationship is poorly defined there is a significant void in our knowledge when it comes to providing simple straight-forward advice to industry on what constitutes a safe amount of repetitive lifting with regards to the prevention of disc injury. This is especially true in environments where the magnitudes of the load lifted and the temporal spacing of the lifts are highly variable.