Spine loading during whole-body free-dynamic lifting.
Marras-WS; Davis-KG; Splittstoesser-RE
NIOSH 2001 May; :1-84
Occupationally-related low back disorders (LBDs) continue to be the leading cause of lost work days as well as the most costly occupational safety and health problem facing industry today. It is also well accepted that many occupationally-related LBDs are associated with materials handling. A major limitation in controlling the incidence of occupationally-related LBDs has been the inability to realistically and accurately assess three dimensional spine loadings that can be compared to spine tolerance limits so that the risk of injury could be assessed. One of the most accurate approaches to assessing spinal loading under three dimensional dynamic lifting conditions has been to employ electromyographic or MG-assisted biomechanical models of the spine. Over the past two decades such a model has been under development in the Biodynamics Laboratory at the Ohio State University. However, historically this model has been isolated to the torso and was not able to assess the impact of whole body motions such as deep knee bending upon the loading of the spine. This project has been able to incorporate such adjustments into the model. This was accomplished through a study of lifting behavior and identifying the components of the lift task that needed to be adjusted due to whole body lifting. Instrumentation was developed to asses biomechanical changes in the pelvis and the subsequent changes that occurred in the length-strength relationship of the torso muscles during these lifts. Finally, these changes were implemented into the model and a validation study was performed to assess the model fidelity under these conditions. The major benefit of these changes was to reduce model gain estimates by 9% to more realistic levels and to improve the model fidelity as a function of gender. Thus, adjustments significantly improved model performance to where it is now sensitive to whole body free dynamic lifting situations.
Back-injuries; Injuries; Musculoskeletal-system-disorders; Occupational-health; Injury-prevention; Risk-factors; Spinal-cord-disorders; Models
The Ohio State University, Biodynamics Laboratory, 1971 Neil Avenue, Columbus, OH 43210
Final Grant Report
Disease and Injury; Low Back Disorders
National Institute for Occupational Safety and Health
Ohio State University, Columbus, OH