Thomas Waters, PhD, CPE
Leader, Human Factors and Ergonomics Research Team
Division of Applied Research and Technology
National Institute for Occupational Safety and Health
Work-related musculoskeletal disorders are not going away ... American workers are at a very high risk for occupational injuries.
Good morning. You are in store for a great conference. I have been to this conference four times and it’s exciting to see this turnout of people. I do want to thank Dr. Audrey Nelson for inviting me to speak on what some people might think is a controversial topic, that of the state of the science in musculoskeletal disorders research. You may have heard quotes in the press that there is not enough science in musculoskeletal disorders research to support implementation of ergonomics programs. I hope that after my brief presentation today, you will find those quotes to be inaccurate.
Work-related musculoskeletal disorders (WMSDs) are not going away. In 2001, there were over a half a million (522,528) estimated reportable musculoskeletal disorder (MSD) cases in the United States that resulted in days away from work. About half of those cases (219,665) involved lifting, and another 13% involved some type of awkward posture such as bending, climbing, reaching, and twisting. Of those injuries, about 60,000 recordable MSD causes were due to repetitive motion. So clearly it is still a big problem in the United States. About a two-thirds (67%) of the reported musculoskeletal cases resulted from overexertion to the back. These statistics are from the U.S. Department of Labor (U. S. DOL), Bureau of Labor Statistics (BLS). Some researchers believe that the BLS data represent an under-reporting of the true rates of MSDs. In terms of the cost to the companies and to industry, the median number of days away from work was eight days, but about one-fourth of those cases involved more than 31 days away from work; so clearly, it’s costing industry a lot of money. American workers are at a very high risk for occupational injuries. Figure 1 shows a summary of BLS data from the Occupational Safety and Health Administration (OSHA) about what has been happening to the lost work day injury rates in private industry over the last twenty years (U.S. DOL, BLS, 2002; OSHA, 2001). Since about 1990, there's clearly been a drop in the number of lost work day cases. But, if you look at the actual numbers on injuries, they are not that different from what they were in 1983, so I wouldn't say we've moved very far. What you can dramatically see is the cases with days away from work have dropped significantly, but there has been a trade-off with those cases with days of restricted work activity increasing significantly. So what we are really seeing is a trade-off in people not having to be off work, but having to shift to a lighter duty job. In some industries, that's just not a possibility because there are no light jobs available for workers to transfer into. For nurses and other caregivers, I don't know what light duty would be available, but I don't think there are very many out there. For health care workers, there aren't too many choices, either you do your job or you don't, that makes it difficult to keep workers on the job.
State of the Science Research
During the past decade, there have been more than 4,000 peer reviewed articles published on the prevention of work-related musculoskeletal disorders.
Some people have argued that there is a lack of science available regarding the relationship between exposure to physical loading and development of MSDs. I would beg to differ from those who hold that position. During the past decade, there have been more than 4,000 peer reviewed articles published on the prevention of work-related musculoskeletal disorders. This is based on the National Library of Medicine (2002) data base, and of those 4,000 articles, a number of those have been very high quality literature reviews (Andersson, 1995; Bernard, 1997; Buckle & Deveraux, 1999; Ferguson & Marras, 1997; Frank, Pulcins, Kerr, Shannon, & Stansfeld, 1995; Frank et al., 1996a, 1996b; Katz et al., 1998; Krause, Dasinger, & Neuhauser, 1998; Moore, 1992; National Research Council, 1999; Panel on Musculoskeletal Disorders, 2001; Rempel et al., 1998; Szabo, 1998; Viikari-Juntura & Silverstein, 1999). Most notably the National Institute for Occupational Safety and Health (NIOSH) Yellow Book, which you may or may not be familiar with, is a large study conducted by NIOSH in 1997 that summarizes the work-relatedness of musculoskeletal disorders (Bernard). There were also two large reviews done by the National Research Council, most recently one that was done in 2001, by the National Research Council and the Institute of Medicine (Panel on Musculoskeletal Disorders). There are many other people who have reviewed the literature all across the world, and the primary conclusion from the reviews is that there is a direct relationship between work and musculoskeletal disorders. Most experts recognize, however, that there is still information we don’t know, but I believe we can improve on the research that we are doing and we can design better studies that control for confounders we didn’t know existed before, such as psychosocial and work organizational factors. We are becoming more familiar with some of these potential confounders or biases and so we are trying to control for these factors. But, that doesn’t mean that the studies we have already done are not important and don’t really point to some common findings. Based on those reviews, I’ve personally come up with what I think are seven main points that you can draw from those reviews and from those 4,000+ articles that have been published.
1. Conceptual Framework for Reviews
The basic model for development of WMSDs is understood [as] ... some kind of physical load on the system ... creates some kind of loading on the back [that] results in an outcome, either positive or negative.
First, the basic model for development of WMSDs is understood. The model shown in Figure 2, which was published by NIOSH, is similar to the model that was presented by the National Academy of Science (NAS)-IOM report. Clearly, what the literature shows is that some kind of physical load on the system, such as patient handling, lifting boxes, or lifting surgical trays in surgery, creates some kind of loading on the back. That loading results in an outcome, either positive or negative. Positive responses would include adaptation, where you increase muscle strength or improve cardiovascular fitness. That’s why we go to they gym, right? Or, it could be a negative outcome, meaning that the outcome could lead to symptoms of musculoskeletal disorders, pain or discomfort, or impairment or disability. Disability and impairment are the things that we really want to avoid, because those are what cost the most money and result in the greatest impact upon the worker. Some symptoms, however, such as psychological affects, may be unrecognized. These symptoms are not always taken into account, but these factors impact a person’s quality of work; these factors affect how a person feels about their job. This is what impacts whether this is a decent job to work in; all of this leads to some negative outcome. But, we also know that there are many other factors that can impact upon this basic process. For example, we know that organizational factors can play a role. For example, if you have lift devices and nobody uses them, that’s an organizational problem. How you get the safety culture changed at a workplace is an organizational factor. Individual factors can affect the outcomes. For example, people who are older, who are obese, may be at increased risk for injury. That is an area that we need to address in more detail. In addition, we need to consider the interactions between these factors. It is believed that these psychosocial factors interact with the physical factors to increase risk of MSDs. For example, if you are having a lot of pain or symptoms or discomfort, that could create an environment where the social context is changed and you don’t react the same way to other people that you work with. So clearly, this is a very complex process. But, I believe we understand the basic framework and that we know the main factors that increase risk of MSDs. Now what we want to do is find out how they interact and how we can fine tune what we know about it, that is where the research in the future will lead us.
2. Exposure-Response Relationship
The NIOSH Lifting Equation (NLE) is an exposure assessment tool ... to determine whether a specific manual lifting task [is] acceptable or not.
The second main point that I would make is that the literature suggests that the risk of musculoskeletal disorders generally increases as the magnitude of the physical factors increases, and that risk is generally higher when there are multiple risk factors. That is consistent with the findings in the NIOSH review, as well as the National Academy of Science review. So, ideologically, we think there’s an exposure-response relationship and we think that science basically supports that, but that’s where we’re working, and I’ll talk a little more about some studies that are ongoing in terms of studies of the exposure-response relationship. An example of a study we did at NIOSH, which is similar to other epidemiological studies that have been done in ergonomics, was a cross sectional study of manual lifting and back pain. In this study, we used the NIOSH lifting equation (NLE) to study exposure to manual lifting. The NLE is an exposure assessment tool which is a simplistic model that we developed so that most people could use it to determine whether a specific manual lifting task was acceptable or not (Waters, Putz-Anderson, Garg, & Fine, 1993; Waters, Garg, & Putz-Anderson, 1994). The NLE includes an equation for calculating the Recommended Weight Limit (RWL) for a manual lifting task and the Lifting Index (LI), which is the ratio of the actual weight lifted (L) divided by the RWL. The LI therefore is a ratio that can go from zero to infinity. The larger the LI value, the greater the risk of low back disorders. In order to evaluate the effectiveness of the LI to determine when the risk increases, we conducted an epidemiological study in which we went out to series of companies and actually measured the lifting indexes of a number of jobs and we looked at the percent of people that reported back pain (Waters et al, 1999). In our study, we found that about 17% of the people in our unexposed group (i.e., those who didn't do any lifting) reported that they had back pain lasting a week or more in the last year. For those people who were in jobs with increasing LI values (i.e., increasing levels of physical stress), we found an increasing trend in people reporting back pain. We found that people who worked in jobs with an LI value between 2.0 and 3.0 were 2 ½ times more likely to have back pain than those in the unexposed group. So, even though this was a cross-sectional study, it shows there’s a relationship. We need to do more prospective studies where individuals are followed over a long period of time to identify what happens to the injuries and illnesses as a function of exposure over time.
3. Multifactorial Nature of MSDs
... both physical factors and psychosocial or work organizational factors likely play a role in the development of MSDs.
The third point that I want to make is based on what I think the reviews say about the multifactorial nature of the etiology of MSDs. By this I mean that both physical factors and psychosocial or work organizational factors likely play a role in the development of MSDs. What we are interested in, is how these psychosocial or work organizational factors impact on loading factors or increase the loading on the tissues. Because most experts believe MSDs are due to physical demands exceeding the tolerance of the tissues, we must figure out how these psychosocial or work organizational factors increase the internal loading of the body. There are several studies that have shown this, most recently one at Ohio State University that showed that pacing (e.g., frequencies controlled by line speeds) and other types of work organizational factors (e.g., cognitive stress) increase the load on the spine because it changes the way people recruit their muscles when they do the lift (Davis, Marras, Heaney, Waters, & Gupta, 2002). So, if in fact work organizational factors interact in a multifactorial way to create higher loads on the body, these interactive effects are likely to put you at increased risk of a MSD. Also, individual factors may have these same kinds of interactive relationships that need more study.
4. Effectiveness of Interventions
... we do know that engineering and administrative controls can be highly effective in reducing risk of MSDs.
Fourth and most importantly is that although we don't know everything about what causes MSDs, we do know that engineering and administrative controls can be highly effective in reducing risk of MSDs. So in other words, even if we don’t know what causes MSDs, we know controls work. We have some examples of studies that show the effectiveness of interventions. A report in 1995 from the Government Accounting Office (GAO, 1997) reported on the evaluation of ergonomic programs in five major companies in varying industries. All had shown significant benefits, particularly reduced worker’s compensation costs. Productivity was not looked at in this study, which is typically a bigger piece of the pie, a bigger piece of the savings than worker’s compensation. Sometimes when you put a program in place you might only minimally reduce the injury rates, but you may have a bigger impact on increasing productivity and quality of the product. All of the ergonomic interventions in the GAO report contained core elements and each program was adapted to meet site specific conditions.
Another series of studies examined the effectiveness of ergonomic interventions. Findings from peer reviewed research show that ergonomic interventions are effective. Since 1990, there have been 15 systematic reviews of the effectiveness of ergonomic interventions, or interventions to prevent musculoskeletal disorders. A recent study by Silverstein and Clark (2004) published in a special issue of the Journal of Electromyography and Kinesiology reviewed numerous studies of ergonomic interventions since 1999. Dr. Silverstein and colleagues identified 20 randomized control studies, 17 quasi-experimental studies, and 36 case studies that evaluated the effectiveness of ergonomic interventions. For the most part, the findings showed that the interventions significantly reduced the risk of MSDs. There were some studies that showed the interventions were not effective in reducing risk, but that is not unexpected.
5. Costs and Benefits of Ergonomic Interventions
Ergonomic interventions make good business sense ... when you implement an ergonomics program, and if you have done it correctly, you're going to significantly decrease your business costs.
Another point that has come up repeatedly both in our National occupational Research Agenda (NORA) team and as well at the National Advisory Committee on Ergonomics is development of the business case for an ergonomics program. Ergonomic interventions make good business sense when done correctly (Collins, Wolf, Bell, & Evanoff, 2004; Garg 1999; Nelson, Lloyd, Menzel, & Gross, 2003). Typically what we find is that when you implement an ergonomics program, and if you have done it correctly, you’re going to significantly decrease your business costs. That will be represented both in increases in production and decreases in worker’s compensation costs. You will increase your product quality and your worker productivity. Product quality for a nurse is important if you think about what nurses do, they take care of sick people. If the quality of their product is not very good, what’s going to happen? People are going to suffer; you are going to have more patient errors and more skin tears. So these types of interventions, the patient lifting and the zero lift programs, all increase product quality in the health care industry. It will also increase workers’ safety, health, and morale.
At the National Institute for Occupational Safety and Health, primary prevention is our first priority. That is, we try to develop interventions that will prevent first occurrences of injuries and illnesses. We try to identify what the exposures are and what the outcomes are likely going to be, and then we develop interventions to prevent injuries. From our perspective, we have found ample evidence of the effectiveness of interventions. To give you an example of what some companies have found, in January 1997 NIOSH and OSHA co-sponsored an ergonomics conference titled “Ergonomics: Effective Workplace Practices and Programs” in Chicago (conference proceedings available at www.cdc.gov/niosh/topics/ergonomics/EWconf97/ecagenda.html). There were more than 1,000 attendees representing more than 80 speakers addressing the effectiveness of ergonomics programs. They represented a wide range of industries from warehousing to health care, to manufacturing. Even though they were representing different companies, the vast majority of speakers had a common message. Ergonomics works, and most spoke about the success of their programs. What I took away from that was to look at the return on investment in the long run even if it may take two to five years. In the health care industry, it might be more dramatic, you might see a return on your investment in less than a year, or it might take several years, but don’t be afraid to keep implementing an ergonomics program. What those companies typically reported, is that the number of injuries actually went up that first year, from the year in which an ergonomics program was initiated. If you were a casual observer you would say this thing isn’t working, let’s forget it, it’s going to get worse. But, what I heard all these companies say is that even though the rates initially went up, they gradually improved over a period of time and eventually, over a two to five years period of time, the program paid for itself. Injury rates dropped and remained down. Most experts recognize that you can not prevent all injuries, and that you will always have a certain number of injuries that you just can’t eliminate. That is, you can’t get to zero injuries, but you can get to zero lift. Even though you may not be able to get to zero injuries, that doesn’t mean it shouldn’t be your goal. You should be aiming in that direction.
6. Effectiveness of Interventions is Dependent upon Multiple Factors
... the effectiveness of a patient lifting device is dependent upon both the effectiveness of the device and the willingness of the health care provider to use it.
The sixth point I would make, and again this is similar to what I’ve said previously, is that intervention effectiveness is usually dependent upon multiple factors. For example, the effectiveness of a patient lifting device is dependent upon both the effectiveness of the device and the willingness of the health care provider to use it. The patient lifting device is a very well designed device and it will really do a good job of lifting a patient, but if the person is not going to use it correctly or doesn’t have the right training, it may not work. I have seen examples of this several times in manufacturing environments. The device can be very effective, but if people aren’t going to use it then it won’t help. Intervention effectiveness is dependent on the fact that the company is willing to invest in this equipment, so you’ve got to get management to buy into it. There are a lot of factors that go into determining whether an intervention is going to be effective. It is not good enough to just look at the device and say that this device reduces loading on the back by 100%. You have to show that it will reduce exposure, that it will be used by the workers, and that it is easy to use. Therefore, success will rely on addressing these multiple factors.
7. One Size Does Not Fit All
The basic principles of reducing exposure ... are very similar across all industries, but equipment and practices will differ.
The seventh and last point in my presentation is that basic intervention principles are applicable across industry, but customization will likely be needed. The basic principles of reducing exposure to the person who is doing the job are very similar across all industries, but equipment and practices will differ. For example, in the health care industry, patient lifting devices aren’t the same devices we would use in a manufacturing industry when we are building a big motor, or when we are lifting cylinders. It’s going to take some customization, but the basic design of that lifting equipment is very similar, so we need to learn to use technology transfer across industries. What we find is very effective in one industry; we need to think about how that technology can be used in another industry. The basic experience we have is that we know enough about injuries, we know what technology works for prevention; we just have to figure out how to move from research to reality, from research to practice. NIOSH has a new emphasis program now called Research to Practice (R2P) that you will be hearing about. NIOSH will be starting to develop more research studies aimed at taking the research that we already have, and taking that down to the applied level. For more information about the NIOSH R2P program, go to the NIOSH web site www.cdc.gov/niosh.
Identifying Research Gaps
I want to switch gears now and talk a bit about what I think the research gaps are. We already know a lot, but I don’t think we know everything and I think we can improve upon what we do know and the way we do our studies. I want to talk briefly about two national groups that identified the most significant research gaps related to work-related musculoskeletal disorders. A summary of the information below appeared in a recent article (Waters, 2004).
The first is the NIOSH/NORA Musculoskeletal Disorders (MSD) team. In 2001, the NIOSH NORA MSD team developed a document that provided input on research gaps from practitioners and academicians (NIOSH, 2001). That report is based on the findings from four large meetings held around the United States; some of you may have attended one or more of these meetings. One was held in Washington DC that focused strictly on health care, and the other three were held in Seattle, Washington; Chicago, Illinois and Houston, Texas. There were nearly 500 attendees and practitioners from industry, labor, and academia who attended the workshops to provide input on our research agenda. That research agenda focused on more of a practitioner viewpoint, rather than an academic viewpoint. The National Research Council (NRC) and the Institute of Medicine (IOM) also developed a report that was published in 2001 that included a review of the science with a published research agenda (Panel on Musculoskeletal Disorders, 2001). The NRC-IOM report represented the findings of 19 experts who gave input and developed conclusions for a research agenda that came primarily from an academic perspective. A copy of the NORA document is available on the NIOSH web page that you can download (www.cdc.gov/niosh/2001-117.html). In examining the research agendas there are a lot of similarities regarding identified research gaps. The gaps can be summarized below:
Gaps in Surveillance and Etiological Research
NIOSH started an initiative to do a national occupational exposure survey...and the first industry to be targeted was the health care industry.
In terms of national studies of work-related musculoskeletal disorders, two primary areas were identified. One area was the need for an ongoing national hazard survey. NIOSH started an initiative to do a national occupational exposure survey called the National Exposure Work Survey (NEWS), and the first industry to be targeted was the health care industry. The study was to be designed for ongoing data collection in hospitals and health care environments regarding exposure to a wide range of occupational hazards, including musculoskeletal hazards. Secondly, it was identified that more prospective and cross-sectional epidemiological studies are needed that examine the dose response relationship between physical loading factors and psychosocial factors, specifically the upper extremity and low back. In the last four years since these two reports were done, NIOSH has made a big push in this direction and has funded several external researchers as well as intramural researchers to develop a large program involving seven to eight research groups to examine the dose-response relationship for both upper extremity, low back, hand/arm vibration and intervention effectiveness. We’ve been moving in this direction, but we need to go a lot further, we need more prospective studies.
Gaps in Exposure Assessment Tools and Methods
We identified ... the need to improve tools for exposure assessment by increasing user friendliness and customizing tools for different ... environments.
We identified in these reports the need to improve tools for exposure assessment (dose) by increasing user friendliness and customizing tools for different kinds of environments. We need to increase the sensitivity and specificity of the tools, to make sure that these tools do what they’re supposed to do and do it accurately. The tools help to identify high risk jobs and people that may be at high risk. The tools should consider physical and psychosocial factors. Since MSDs are a multifactorial problem, we need tools that allow us to look at all these factors in combination. The tools should be multipurpose, not only should they be good for evaluating causality which is what we really want to do with them, but we should be able to use the tools to help design jobs better. The tools help identify problems, and identify the solutions. In the patient handling areas, we have designed a lot of equipment based on data from the assessment tools.
Gaps in Definitions and Medical Issues
Another important research gap is the need for improvement of the definitions of health outcomes ... [such as] a standardized case definition for WMSDs.
Another important research gap is the need for improvement of the definitions of health outcomes, we need to develop and validate a standardized case definition for WMSDs. This has been a big issue with OSHA. You may have heard that they deleted the column from the OSHA log, it was proposed on the OSHA 300 log for documenting work-related injuries and illnesses to have a category for WMSDs and but they decided not to put that on. We think that’s important and that it should be on that OSHA 300 log. The use of standardized case definitions is an area where NIOSH and other agencies such as the Veterans Administration (VA) and other agencies could play a role in helping to standardize the definitions. We need precise diagnostic tools for identifying musculoskeletal disorders. Some of the tools are not as objective as we would like. There is a lot of research going on in this area. Dr. Marras (from Ohio State University) for example, is looking at the lumbar motion monitor (LMM) as a clinical tool and that would perhaps help in the diagnosis of WMSDs. We need improved guidelines for effective treatment and return to work. We need to find out what works, why it works and how we can make it work better.
Gaps in Evaluating Effects of Interactions Between Risk Factors
We need to clarify the interaction of risk factors. We need to further investigate the interaction between physical and psychosocial factors and the effects of individual factors. In terms of disease causation, mechanobiology studies (animal studies) are needed as well as biomechanical studies and psychosocial stress studies. There is research going on in that area on pain management and training on how to deal with stress in the workplace.
Gaps in Evaluating the Effectiveness of Ergonomic Interventions
Again, we recognize the fact that interventions work, but we think that we need to develop and test new engineering controls, evaluate the cost/benefits of interventions, and demonstrate relative effectiveness of interventions, such as engineering controls vs. administrative (training and placement) versus personal protective equipment. There’s a hierarchy of controls at NIOSH, you should first look at engineering controls and then only as a last resort look at administrative controls, and at some workplaces we recognize the fact that those administrative controls may be just as important as the physical ones. For example, if the people aren’t trained in how to use the lift equipment properly they are not going to use it. We need more studies to demonstrate the effectiveness of that so that more companies would be willing to buy into this and actually start developing these programs and using this equipment.
Applying the Research
Next, I want to present some useful ergonomic information that I think you might find of value.
- NIOSH Website (www.cdc.gov/niosh) Provides lots of useful information and publications about ergonomics that can be downloaded to your computer, including:
- “Elements of Ergonomics Programs”
- “Applications Manual for Revised NIOSH Lifting Equation”
- Hundreds of NIOSH Hazard Evaluation and Technical Assistance (HETA) reports that you can search for online on the NIOSH web site, many which involve the health care industry.
- CAL/OSHA Website (www.cal-osha.com) This website contains numerous ergonomics documents including:
- “Easy Ergonomics” a very nice document that summarizes ergonomics
- OSHA Website (www.osha.gov) Contains useful information about ergonomics and ergonomics assistance.
- Washington State Dept. of Labor Website (www.lni.wa.gov) This website has lots of information about ergonomics, including an ergonomics idea bank (www.lni.wa.gov/Safety/Topics/ReduceHazards/ErgoBank/default.asp).
- University of South Florida Website (http://hsc.usf.edu/~tbernard/ergotools/) Dr. Thomas Bernard at the University of South Florida has developed a website with a number of easy to use ergonomics assessment tools and checklists.
State of the Art Research Symposium (STARS)
I want to talk briefly about a more recent conference that was held in Columbus, Ohio in 2003 titled “State of the Art Research Symposium: Perspectives on Musculoskeletal Disorder Causation and Control” (STARS). There were 19 papers that resulted from that conference now available in a special issue of Journal of Electromyography and Kinesiology, Volume 14, Number 1, February 2004, published by Elsevier publishers. These 19 papers cover a range of topics related to musculoskeletal disorders (MSDs) epidemiology and economics, loading biomechanics, biomechanical and physiological tolerance, traditional and non-traditional pain perception, individual and genetic factors, and primary and secondary interventions. These were 19 of the leading scientists that came and talked about all the wide range of topics, so it provided the opportunity for interaction among people who studied these different areas of research and from that there was a discussion about where research efforts are currently and where they should be in the future.
Health Care Ergonomics
The most important issue identified as a big problem in the health care industry was that of patient handling.
Another conference that was sponsored by the NIOSH NORA MSD team occurred a few years ago. In conjunction with the Third Annual Applied Ergonomics Conference in Los Angeles, California, March, 2000, a special meeting was held to focus on ergonomics research gaps in the health care industry. There were representatives from the health care industry, research community and insurance providers. They were asked to provide input about the research issues or research gaps related to prevention of MSDs in the health care industry. The most important issue identified as a big problem in the health care industry was that of patient handling. The attendees thought that "no lift" or "zero lift" programs and possibly lift teams were a great idea, but more studies are needed on the effectiveness of the lifting equipment and teams and cost benefits, and how they operate. Exploring the scheduling of patient handling activities, and how patient handling is reduced by design, for example, using adjustable beds and new designed beds and new types of equipment are important areas to explore. They also thought it was important to look at the relation between occupational injuries and medical errors. This is a big problem and I know that the American Nurses Association and NIOSH are interested in the relationship between worker protection and patient safety and quality of care. Transferring patient handling knowledge to the home health care industry was addressed and that’s an area that was addressed last year at this conference and two speakers are going to talk about at today’s conference. The home health care environment is a completely different environment than a hospital or a nursing home. The devices that are useful in the hospital or in the nursing homes may not be very effective in the home health care environment. The question of "How we transfer this patient handling knowledge to the home health care environment?", is an area that needs much research.
Dr. Audrey Nelson, RN, at the Tampa Veterans Administration ... has developed a series of algorithms for selecting the proper lifting equipment.
The problem of protecting the patient versus protecting the health care worker has been identified as a big problem, in regards to patient errors and protecting the patient, you also have to think about the worker and how you can do both at the same time. How can you increase the ability to protect the caregiver and at the same time protect the person receiving the care? Research is needed to compare and evaluate patient handling devices. We recognize that using devices is the best solution, but we need to compare and contrast these so that we come up with a better understanding of what works, what doesn’t, what should we use, and when. Much work is being done by Dr. Audrey Nelson, RN, at the Tampa Veterans Administration (VA). She has developed a series of algorithms for selecting the proper lifting equipment (Nelson, 2001). The algorithms have been proposed for use by the Veterans Health Administration and are contained in the recent OSHA ergonomic guidelines for nursing homes (U.S. DOL, OSHA, 2002). These algorithms describe how to determine the right equipment to use for a specific patient handling activity, such as moving a person from a bed to a chair, or from a bed to gurney, etc.
More research in the area of patient acceptance is needed. Transfer time needs to be considered by asking these questions: What are the trade-offs between the transfer time and doing the lift either with a lift team or just having the equipment available? Which are better to use, ceiling lifts or portable floor-based lifts? What equipment is safest and easiest to use. How many operators are needed? Is the device adaptable, can it be used in many different environments? Is it flexible? How are patient characteristics considered, such as using the equipment for bariatric (extremely heavy) patients? What is the adaptability of the device? This is a big problem because some equipment will not work with bariatric patients. We need to examine this particular part of the health care industry and look at how this equipment can be developed. We need to explore portability issues, especially for home health care; a patient lifting device that is light weight and portable has to be easily transported, otherwise health care providers can’t take it into the home.
Improved Patient Handling Equipment
... we have come a long way in recognizing that "no lift" or "zero lift" programs are effective and should be supported in most health care environments.
This is an area where research is needed. We need new patient handling equipment that is designed for improved portability and patient handling needs, but is fast and easy to use. We need devices to eliminate or assist with lateral patient transfer. We also need to continue research on fall prevention though proactive measures. Although research gaps remain, we have come a long way in recognizing that "no lift" or "zero lift" programs are effective and should be supported in most health care environments. There is a lot of patient handling equipment available, but we need to continue research studies to develop new ways to use it and to train caregivers in the proper use and maintenance of the equipment.
We need to examine the effectiveness of certain ergonomic interventions, such as gait belts. Some believe that we need a systems approach, where we approach the environment as a whole, rather than individual elements of a program. Questions remain, such as "How do you design a hospital facility with prevention of musculoskeletal disorders in mind?" That is a huge task, and if you are building a new health care facility, then it should be designed correctly to begin with. More research is needed to identify the best design elements. What are the best design characteristics that should be incorporated in all new health care facilities as they’re being developed and built? Self-directed teams and ergo programs have been identified as an area in need of research. With the emphasis on aging, it has been recognized that the American work force is also aging. If you review some of the statistics, especially social security, people now have to work until a later age.
Questions remain, such as " How do you design a hospital facility with prevention of musculoskeletal disorders in mind?"
Many people are working way past what they normally would have worked back in the 1960s and 1970s, now they’re working into their 60s, 70s and 80s. With the average age of nurses being 50 years or greater, and if you think about the normal distribution of the work force, you skewed that work force way over to the aging side. This is not to say that you are old, but we have to understand this and that is why the research is needed. The issue of handles integrated into garments, I don’t know if anybody’s doing any research on that, I thought it was a great idea when I heard it at last year’s conference. We need to explore the safety issues associated with these types of garments.
At last year’s conference I presented on the pushing/pulling forces for the floor mounted lifts. More research is needed on push/pull forces in patient handling with reference to cart design, castor design/maintenance, floor surfaces, cornering ability, and motorized carts. It is people who use carts to deliver food and deliver medications who are having a huge problem because of the big heavy carts that they are pushing. People do this for hours and hours, every day, so I believe more research is needed to look at some of these factors, to improve the design of food delivery systems and medication delivery systems. We need to examine purchasing guidelines for patient care. This is an area that we probably have not done a good job of and maybe this is an area that we need to explore. There are thousands and thousands pieces of equipment out there we have to pick and chose from. The patient handling guidelines that have been developed help you decide what to chose, but you need purchasing guidelines for deciding: What is best for your facility?, What can you afford?, What are the tradeoffs for determining how does your work environment differs from another work environment?
We need to disseminate the research evidence much faster ... The old adage of "Keep your back straight, bend your knees and lift" just won't work anymore.
Let me just summarize with a few conclusions here. First there has been a tremendous amount of research conducted in this area of musculoskeletal disorders, so if you hear someone say that there is no science to back up ergonomics, I don’t believe that and I don’t think you should believe it either. Secondly, the basic conceptual framework for how musculoskeletal disorders develop is pretty well understood. We believe that effective interventions are available; the health industry is the best example of where this kind of intervention effectiveness has proved the most valuable. We recognize that many research gaps remain, we think that we can improve the research process, but I think it’s more important to ask, How can we take the research and get it into reality within an appropriate amount of time? We have to disseminate the research evidence much faster. Priority should be given to engineering approaches over administrative controls. The old adage of “Keep your back straight, bend your knees and lift” just won’t work anymore. Teaching people safe patient handling is good if you’re using the right equipment and if you are using the right type of process and you have the right organizational structure. In closing, I would say that we know a lot, we need to do more, if you are interested in research, NIOSH would be happy to talk to you. We have an extramural grants program, it’s very competitive, but it can be very rewarding if you are willing to go through the process (NIOSH, 2004). Thank you.
Figure 1. Incidence rate for lost workday cases 1982-2001
Figure 2. Basic model for development of MSDs
Thomas Waters, PhD, CPE
E-mail Address: TRW1@CDC.GOV
Dr. Waters is Leader of the Human Factor and Ergonomics Research Team in the Division of Applied Research and Technology at the National Institute for Occupational Safety and Health (NIOSH) in Cincinnati, Ohio . His research team is composed of engineers and psychologists and multiple support staff involved in research in the area of biomechanics, industrial engineering, industrial hygiene, ergonomics, and human factors. He is also Chair of the NIOSH National Occupational Research Agenda (NORA) musculoskeletal disorders team. This is a group of experts that includes representatives from business, labor and government responsible for developing and implementing a national scientific research agenda for preventing musculoskeletal disorders. Dr. Waters is internationally known for his expertise in the area of prevention of occupational low back pain and his development of the revised NIOSH lifting equation. He has published numerous research papers and most recently published a paper evaluating the state of the science in ergonomics research that has identified the next steps for logically moving forward to build a science on safety for patient handling and movement. His efforts have made a major contribution in moving this science forward.
Andersson, G.B.J. (1995). Epidemiology of occupational neck and shoulder disorders. In: Repetitive motion disorders of the upper extremity. In S.L. Gordon, S.J. Blair, & L.J. Fine (Eds.), Proceedings of American Academy of Orthopaedic Surgeons Symposium; Workshop, Bethesda, MD, June 1994 (p.31 B 42). Rosemont, IL: American Academy of Orthopaedic Surgeons .
Bernard, B. (Ed.). (1997). Musculoskeletal disorders and workplace factors. A critical review of epidemiologic evidence for work-related musculoskeletal disorders of the neck, upper extremity, and low back. DHHS (NIOSH) Publication No. 97-141. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health..
Buckle, P., & Devereux, J. (1999). Work-related neck and upper limb musculoskeletal disorders. Luxembourg : European Agency for Safety and Health at Work.
Collins, J.W., Wolf, L., Bell , J., & Evanoff, B. (2004). An evaluation of a “best practices” musculoskeletal injury prevention program in nursing homes. Injury Prevention,10, 206-211.
Davis, K.G., Marras W.S., Heaney, C.A., Waters, T.R., & Gupta, P. (2002). The impact of mental processing and pacing on spine loading. Spine, 27(25), 2645-2653.
Ferguson, S., & Marras, W. (1997). A literature review of low back disorder surveillance measures and risk factors. Clinical Biomechanics, 12, 211-226.
Frank, J.W., Brooker, A.S., DeMaio, S.E., Kerr, M.S., Maetzel, A., Shannon, H.S., et al. (1996a). Disability resulting from occupational low back pain, Part II: What do we know about secondary prevention? A review of the scientific evidence on prevention after disability begins. Spine 21, 2918-2929.
Frank, J.W., Kerr, M.S., Brooker, A.S., DeMaio, S.E., Maetzel, A., Shannon, H.S., et al. (1996b). Disability resulting from occupational low back pain, Part I: What do we know about primary prevention? A review of the scientific evidence on prevention before disability begins. Spine, 21, 2908-2917.
Frank, J.W., Pulcins, J.R., Kerr, M.S., Shannon , H.S., & Stansfeld, S.A. (1995). Occupational back pain: An unhelpful polemic. Scandinavian Journal of Work and Environmental Health, 21, 3-14.
Garg, A. (1999). Long-term effectiveness of “Zero-Lift Program” in seven nursing homes and one hospital. Contract Report No. U60/CCU512089-02, University of Wisconsin-Milwaukee. Milwaukee, WI: University of Wisconsin-Milwaukee.
Government Accounting Office. (1997). Worker protection: Private sector ergonomics programs yield positive results. Government Accounting Office Report No. GAO/HEHS-97-163. Washington, DC: Government Accounting Office.
Katz, J.N., Lew, R.A., Bessette, L., Punnett, L., Fossel, A.H., Mooney, N., et al. (1998). Prevalence and predictors of long-term work disability due to carpal tunnel syndrome. American Journal of Industrial Medicine, 33, 543-350.
Krause, N., Dasinger, L.K., & Neuhauser, F. (1998). Modified work and return to work: A review of the literature. Journal of Occupational Rehabilitation, 8, 113-139.
Moore, J.S. (1992). Carpal tunnel syndrome. Occupational Medicine 7, 741-763.
National Institute for Occupational Safety and Health (NIOSH). (2001). National occupational research agenda for musculoskeletal disorders: Research topics for the next decade. A report by the NORA musculoskeletal disorders team. DHHS [NIOSH] Publication Number 2001-117. Cincinnati, OH: Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health.
National Institute for Occupational Safety and Health (NIOSH). (2004). Office of extramural programs. Available: www.cdc.gov/niosh/oep/funding.html.
National Library of Medicine. (2002). PubMed literature search. Retrieved March, 25, 2002, from: www.ncbi.nlm.nih.gov/PubMed.
National Research Council. (1999). National research council work-related musculoskeletal disorders - Report, workshop summary, and workshop papers. Washington DC: National Academy Press.
Nelson, A. (Ed.). (2001). Developing a no lift policy. Tampa , FL: Department of Veterans Affairs VISN 8 Patient Safety Center.
Nelson, A., Lloyd, J.D., Menzel, N., & Gross, C. (2003). Preventing nursing back injuries: Redesigning patient handling tasks. AAOHN Journal, 51(3), 126-134.
Panel on Musculoskeletal Disorders and the Workplace, Commission on Behavioral and Social Sciences and Education. National Research Council & Institute of Medicine. (2001). Musculoskeletal disorders and the workplace: Low back and upper extremities. Washington, DC: National Academy Press.
Rempel, D., Evanoff, B., Amadio, P.C., de Krom, M., Franklin, G., Franzblau, A., et al. (1998). Consensus criteria for the classification of carpal tunnel syndrome in epidemiologic studies. American Journal of Public Health, 88, 1447-1451.
Silverstein, B., & Clark, R. (2004). Interventions to reduce work-related musculoskeletal disorders. Journal of Electromyography and Kinesiology, 14, 135-152.
Szabo, R.M. (1998). Carpal tunnel syndrome as a repetitive motion disorder. Clinical Orthopedics, 351, 78-89.
U.S. Department of Labor, Bureau of Labor Statistics. (2002, December). Lost workday case incidence rates, injuries, and illnesses, private industry 1982-2001. Available: www.bls.gov/iif/oshwc/osh/os/osch0024.pdf.
U.S. Department of Labor, Occupational Safety and Health Administration. (2001). Number of non-fatal occupational injuries and illnesses with days away from work involving musculoskeletal disorders by selected worker and case characteristics, 2001. Retrieved May, 19, 2002 from: http://stats.bls.gov/iif/oshwc/osh/case/ostb1154.pdf
U.S. Department of Labor, Occupational Safety and Health Administration. (2002). Ergonomics guidelines for nursing homes. Retrieved June 22, 2003 from: www.osha.gov/ergonomics/guidelines/nursinghome/final_nh_guidelines.html.
Viikari-Juntura, E., & Silverstein, B. (1999). Role of physical load factors in carpal tunnel syndrome. Scandinavian Journal of Work and Environmental Health, 25, 163-185.
Waters, T.R. (2004). National efforts to identify research issues related to prevention of work-related musculoskeletal disorders. Journal of Electromyography and Kinesiology, 14, 7-12.
Waters, T., Baron, S., Piacitelli, L., Putz-Anderson, V., Skov, T., Haring-Sweeney, M., et al. (1999). Epidemiological evaluation of the revised NIOSH lifting equation: a cross sectional study. Spine, 24(4), 386-395.
Waters, T., Garg, A., & Putz-Anderson, V. (1994). Applications manual for the revised NIOSH lifting equation. DHHS(NIOSH) Pub. No. 94-110. Cincinnati, OH: Department of Health and Human Services, National Institute for Occupational Safety and Health, Division of Biomedical and Behavioral Science.
Waters, T., Putz-Anderson, V., Garg, A., & Fine, L. J. (1993). Revised NIOSH equation for the design and evaluation of manual lifting tasks. Ergonomics., 36(7),749-776.