February 2, 2001

 National News

Long-awaited ergonomics study fails to clarify causes, cures
The National Academy of Sciences’ long-awaited study of the causes and cures of musculoskeletal disorders, which was released on Jan. 18, found that while some jobs can be associated with injuries to the back, wrist and other areas, the work-injury relationship is complicated by many factors, including some that are beyond an employer’s control. Business interests said the study’s less-than-crystal-clear conclusions prove that the U.S. Labor Department’s ergonomics regulation is “scientifically shaky” and should be overturned.

“The NAS study proves that OSHA’s ergonomics regulation is nothing more than a house of cards built on a rickety foundation of questionable science and statistics,” said Jenny Krese, director of employment policy at the National Association of Manufacturers.  “If there ever was any doubt that the rule should be overturned by Congress or the courts, this study removes it by underscoring both the lack of clarity about the exact causes of musculoskeletal disorders (MSDs) and the fact that the rule was issued before the Congressionally-ordered study was complete.”

Business groups said the lack of clarify in the 450-page study supports their contention that President Bush and Congress should intervene to halt enforcement of the ergonomics regulations, which now are scheduled to go into effect in October. “Delaying enforcement of the ergo rule – to allow a full review of the NAS study – and reopening the rulemaking process should be the first order of business for the White House and Congress after inauguration,” said Randel Johnson, U.S. Chamber of Commerce vice president for labor policy.

Others in the business community said the study’s release – just two days before the end of the Clinton administration – shows that the study may have been politically influenced. But OSHA administrator Charles Jeffress said the study validated his agency’s call for new workplace safeguards. “This study affirms what OSHA found in its rule making, that in fact these disorders are work-related and that ergonomics programs do make a difference,” Jeffress said.

“Even setting aside the NAS study’s contradictory conclusions, we are troubled that a sweeping and stringent ergonomics rule was put in place without the benefit of this Congressionally-mandated analysis,” said National Coalition on Ergonomics Chairman Ed Gilroy. “The fact that the Clinton Administration issued its ergonomics regulation before the completion of the study is just more evidence that it is a shot-in-the-dark scientifically and should be addressed by both Congress and the new Bush Administration.”

“Despite the study’s implied support of OSHA’s ergonomics regulation, it actually reinforces the business view that there is a lack of sound scientific evidence on the causes of musculoskeletal disorders (MSDs) by acknowledging the wide array of complicated, unquantifiable and subjective factors that contribute to these disorders,” Gilroy continued. “The study also calls for more research and better statistics on MSDs, something the business community has been urging for years.”

Strengthening the argument by the business community that the National Academy of Sciences’ study is incomplete at best is a stinging dissent written by one of the scientists who composed the panel.  Dr. Robert B. Szabo, chief of the Department of Orthopedics at the University of California at Davis, particularly disagreed with study’s conclusion that carpel tunnel syndrome can be caused by performing certain jobs, particularly typing on a computer keyboard. He said the panel based that conclusion on a few narrow, incomplete studies. “To circumvent the issue of not having reasonable scientific intervention studies available,” Szabo wrote in his dissent, “the panel took a ‘best practices’ approach, which I think is not very scientific.”

Szabo went on to site several other studies which the panel ignored that undermine its conclusion typing at a computer causes carpal tunnel syndrome. The only valid conclusion that can be reached, he said is “it is not universally accepted that job-related factors are important determinants for predicting the appearance of carpal tunnel syndrome. In the general population, its prevalence is the same whether people perform repetitive activities or not.”

Later in his dissent, Szabo said “occupational risk factors alone do not explain its (carpal tunnel syndrome) occurrence; rather, it is the culmination of many distinct converging causal links. The majority of cases are likely due to intrinsic risk factors.” He went on to point out several studies which found very strong links between carpal tunnel syndrome and a person’s weight and whether they used tobacco or drank coffee. Szabo particularly focused on a study by the U.S. Navy that found strong correlations between carpal tunnel syndrome and a person’s age, sex and race.”

Szabo blasted the panel for suggesting that it had been proven by one study that a kind of ergonomic keyboard could prevent carpal tunnel syndrome. “The authors of this small study,” Szabo said, “explored the use of an alternative keyboard design on hand pain in patients already diagnosed with carpal tunnel syndrome and measured symptoms of pains. The participants abandoned the use of these alternative keyboards despite a ‘positive’ effect. One might be led to believe by the (NAS) report that this study prevented carpal tunnel syndrome or provided evidence of a worthwhile intervention. I don’t think so.”

The NAM’s Krese said that the only logical conclusion that can be drawn from the NAS report is that there are complex causes of MSDs, not all of which are understood. “While we strongly believe the panel was biased in favor of the regulation, we welcome the study’s admission that there are dozens of complex and difficult-to-determine factors that contribute to MSDs, including age, gender and social context, among others,” she said. “The release of the NAS study energizes our arguments about the need to overturn the ergonomics regulation on both procedural and scientific grounds, and we intend to use it in our efforts to ensure that employers and employees are not forced to comply with this rigid, overreaching and unsound rule,” she concluded.

The ergonomics rules were included among the items that aides to President Bush have indicated were subject to reconsideration by the new administration. However, overturning the rules could be complex, requiring a new rulemaking process that could take months.

Want to know more about the issue? NCCBI, which has joined with other groups in a national lawsuit against enforcement of the new ergonomics rules, previously published an extensive briefing paper on ergonomics as well as a detailed account of how the rules will impact your business.

The academy’s report said scientific evidence shows that disorders of the lower back and upper extremities can be attributed to working at particular jobs, including those involving heavy lifting, repetitive and forceful motions and stressful environments. “However, the connection between the workplace and these disorders is complex, partly because of the individual characteristics of the workers – such as age, gender and lifestyle,” commented Jeremiah A. Barondess, chairman of the panel that wrote the report. Barondess is president of the New York Academy of Medicine.

The study found that back pain made up the overwhelming share of workplace problems, along with muscle and bone disorders and wrist injuries, including carpal tunnel syndrome. It estimated that these maladies cost the country $45 billion to $54 billion annually in compensation, lost wages and lowered productivity. The report said programs can be developed to reduce these injuries, but must be tailored to specific workplaces.

Because the nation lacks a uniform and comprehensive method to gather and track data on MSDs, a coordinated and standardized data-collection system is needed, the report adds. To that end, the Bureau of Labor Statistics should provide more comprehensive surveillance of work-related MSDs by obtaining from employers specific information about jobs, workplace illnesses, and the characteristics of workers performing certain jobs. Standardized coding procedures and more precise and consistent descriptions of risk factors also should be developed for large data systems.

The report calls on the National Institute of Occupational Safety and Health to expand the scope of its research and training activities, and to take the lead in creating definitions of musculoskeletal disorders for research and other purposes—measures that would require funding increases.

Musculoskeletal disorders, or MSDs, is the medical term that refers to health problems affecting muscles, nerves, spinal disks, joints, cartilage, tendons, and ligaments. Many of these disorders occur in the lower back and upper extremities, which include the shoulders, arms, and hands. When the Occupational Safety and Health Administration began making plans to implement regulations covering MSDs in the workplace, Congress asked the National Academies to review scientific evidence on work-related causes of MSDs as well as prevention strategies. The Academies’ panel evaluated scientific literature on the topic, invited outside experts to share insights at its meetings, and visited two Ford Motor Co. plants as part of its research.  

The study, requested by the U.S. Department of Health and Human Services, was issued by the National Research Council and the Institute of Medicine, two branches of the National Academy of Sciences. The academy is a private organization chartered by Congress to advise the government. Copies of the study can be purchased from the NAS for $46. Click here for information on ordering. Other sites of interest:

National Academy of Sciences: http://www.nas.edu
Occupational Safety and Health Administration: http://www.osha.gov
National Association of Manufacturers: http://www.nam.org
National Coalition on Ergonomics: http://www.ncergo.org 

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