Musculoskeletal disorders are a leading cause of work-related injuries in the United States. For example, musculoskeletal injuries to the trunk account for 32% of all compensable injuries and 42% of the compensation costs. The largest single category of low back injuries is the ‘sprains/strains’ group. For the past three years the National Institute for Occupational Safety and Health (NIOSH) has waged an aggressive two-phased campaign initially aimed at controlling occupational musculoskeletal injuries and eventually designed to preventthe initial occurrence of a musculoskeletal injury. The key words in the government perspective are ‘control’ and ‘prevent’. The ability to adequately define the musculoskeletal injury is implicit in the words ‘control’ and ‘prevent’ An adequate clinical definition of a musculoskeletal injury is the most elusive of all components in this research area. Subsequent to the adequate clinical definition, steps may be initiated to control musculoskeletal injuries. With the knowle...