Figure 1. Conceptual model of factors that potentially contribute to musculoskeletal disorders.
Work-related musculoskeletal disorders (MSD), such as low back pain, tendinitis, hand-arm vibration syndrome and carpal tunnel syndrome, account for a major component of the cost of work-related illness in the United States. Recent estimates of the costs associated with work-related musculoskeletal disorders range from $13 to $54 billion annually. Regardless of the estimate used, the problem is large both in health and economic terms. The enormous scope of the problem is confirmed by statistics from the Annual Survey of Occupational Injuries and Illnesses, conducted by the Bureau of Labor Statistics (BLS). For those cases involving days away from work, BLS reports that in 1997 approximately one third of the total, or 603,096 cases, were the result of overexertion or repetitive motion. Specifically:
The National Institute for Occupational Safety and Health (NIOSH) recognizes that addressing a problem of such magnitude requires coordination and cooperation among its many external partners. This philosophy underpins NIOSH's National Occupational Research Agenda (NORA), a collaborative effort between NIOSH and its partners to guide occupational safety and health research in the 21st century. As part of the NORA process, a team of experts representing a broad range of industry, labor, and government interests has been assembled to evaluate the status and define future research needs in the area of work-related MSD. (Team members are listed at the front of this document.) This team has developed a National Occupational Research Agenda for MSD that should serve as a blueprint for building a national research program by identifying high priority research problems and influencing the allocation of resources. Implementation of the agenda will be an ongoing effort requiring an active exchange of information among all interested partners.
During the past decade, approximately 4,000 articles that focused on occupationally-related MSD were published. The findings from many of these publications have been summarized in various literature reviews (Anderson 1995; Buckle and Devereux 1999; Frank et al. 1995; Frank et al. 1996a, 1996b; Katz et al. 1998; Krause et al. 1998; Moore 1992; Rempel et al. 1998; Szabo 1998; Viikari- Juntura and Silverstein 1999; NIOSH 1997; Ferguson and Marras 1997; NRC 1999). Based on a synthesis of the findings from these publications, a simple conceptual framework of factors that can contribute to MSD can be formulated (see Figure 1). In this model, initial loads are applied to the musculoskeletal system either by external forces or by internal forces resulting from dynamic and gravitational effects on the mass of the body segments. These applied loads create internal tissue responses in the muscles, ligaments, and at the joint surfaces. Depending upon the magnitude of the load and other individual, organizational, or social factors, one or more outcomes may result. These may include adaptation effects (such as increases in strength, fitness, or conditioning) or potentially harmful outcomes (such as pain or other symptoms, and structural damage to tendons, nerves, muscles, joints, or supporting tissues) that may result in symptoms, impairment, or disability. Whether the exposure leads to an MSD depends upon the physical demands of the job, the adaptation response of the worker, and other individual physical and psychological factors. These in turn may modulate the effects of the external load.
Interventions designed to reduce risk of MSD can be implemented anywhere along this pathway. Engineering interventions that reduce intensity, frequency, and duration of exposure are often effective.
To obtain maximum input from practitioners, academic and corporate researchers, and organizations sponsoring research, the team adopted a multi-phase approach for seeking input on the national research agenda. The first phase involved sponsorship of three regional focus group meetings where practitioners from a wide range of industry sectors were asked a series of questions regarding research gaps, intervention effectiveness, surveillance, and implementation needs. The three meetings included representatives from light and heavy manufacturing, warehouse and transportation, office environments, acute and long-term health care, forest products, construction and maritime, agriculture, and food processing. During the second phase, academicians and researchers participated in a workgroup meeting using the findings from the practitioner focus groups as the basis for further discussions.
Three practitioner focus groups were held in Chicago, Seattle, and Washington, D.C., and a researcher workgroup meeting was held in Houston. Overall, there were more than 150 focus group attendees in the three meetings (in 16 groups) and over 50 researchers (in five workgroups) at the Houston meeting. The Chicago focus group included representatives from agriculture, food processing, light manufacturing, office work environment, warehouse and transportation, health care, and heavy manufacturing. The Seattle focus group included representatives from forest products/agriculture, construction/maritime, health care, heavy manufacturing, office work environment, and transportation/warehousing/light manufacturing. The Washington D.C. focus group included representatives from two major areas of the health care industry organized into three general health care groups and one long-term health care group. The Chicago, Seattle, and Washington D.C. focus groups attendees were asked to respond to three basic questions:
Surveillance What methods do you think need to be developed to improve your ability to identify hazardous jobs (or working conditions) in your company or industry?
Research Gaps What are the ergonomic problems in your workplace for which there was insufficient research to address the problems?
Intervention What methods have you used that appear to be most effective or promising in reducing the frequency and/or severity of MSD in your workplace and deserve further research and development?
NORA Team MSD team members reviewed the transcripts and flip charts from each of the three practitioner focus group meetings and summarized them using a criteria-based extraction process. These assessments resulted in the development of listings of research issues by industry sector and a short summary statement reflecting the main topics of discussion. The focus group summaries were further analyzed using a manual search and extraction process by combining the results into a single file and then extracting and organizing the material into four listings of research issues by topic area: 1) Surveillance of Musculoskeletal Disorders and Related Hazards, 2) Etiologic and Medical Research, 3) Intervention Research, and 4) Improving the Research Process. Each of the four sections were then edited to consolidate ideas that were similar.
In addition, new ideas contributed by the academicians and researchers at the Houston workgroup meeting were added to the listings. The resulting four lists of research issues are provided in Appendix A. These lists are designed to provide comprehensive inventories of the issues only and do not provide any indications about what the NORA MSD team believes about the priority or importance of individual research issues. Some of the issues identified in the focus groups applied to more than one industry, while others were primarily applicable to specific industries. The selected industry-specific topics are listed in Appendix B. The Houston workgroup was asked to identify research topics where progress seemed most likely in the next five years. Those ideas are listed in Appendix C.
![[Participants in a conference room]](images/midwest.gif)
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