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The ergonomics lab works closely with computational modeling experts in LLNL's Institute for Scientific Computing Research. This modeling capability, the program's second significant resource, is being applied to the study of human-machine interactions. For example, ergonomics laboratory data help validate the work of LLNL bioengineer Karin Hollerbach, who is developing a dynamic computational model of the bones and joints that are often associated with these injuries. (See September 1996 S&TR, pp. 19-21).
Biomedical engineer Robert Van Vorhis, who coordinates the ergonomics lab, also heads the technical aspects of a project to enhance a physician's visualization during endoscopic surgery for carpal tunnel syndrome. Improvements in endoscopic surgery could improve the cure rate of this minimally invasive surgical procedure such that, when it is successful, employees return to work in two weeks instead of six. This project is also leveraging Livermore's capabilities in optics and digital imaging with spinoff applications in advanced manufacturing.
The ergonomics research program's third major resource is Health Services' occupational health clinic (see photo at top), which has expertise in the diagnosis, treatment, and rehabilitation of WRMSDs. Livermore physicians and nurse practitioners diagnose and manage problems while physical therapists administer on-site treatment.
Finally, LLNL's large, stable, and innovative workforce provides excellent subjects for testing new products in the workplace and for providing valuable feedback. "We are a mini-town, with every profession represented, including editors, administrators, accountants, computer scientists, physicists, technicians, and engineers," says Burastero. All use computers differently, and most, he adds, are not shy about voicing their ideas and problems concerning computer usage.
With these four resources--laboratory, computer modeling, clinic, and employees--Livermore is providing a better picture of how these injuries are initiated and prevented and the role that computer accessories play in prevention and cure. Burastero says combining data from laboratory studies, workplace observation, long-term subject feedback, and expert medical monitoring is much preferable to other methods that consist solely of testing people in a controlled setting for a few hours or lending them a product to try.
Much of the research program's focus has been studying recent alternatives to standard computer keyboards. Conventional keyboards have been suspected of causing or exacerbating WRMSDs because their design can encourage use with wrists bent into awkward postures. Burastero notes that keyboards really have not changed much during the past 30 years--witness the host of "vestigial keys" such as "scroll lock" that date from the PC's earliest days.
Pat Tittiranonda, an ergonomist with the program, recently completed the most comprehensive computer-keyboard study ever performed. The three-year study involved 80 participants representing a broad range of occupations at Livermore. All had suffered WRMSDs such as carpal-tunnel syndrome or tendonitis. The volunteers were given one of four alternate keyboards to use for six months. The keyboards had been developed and marketed by different companies with the goals of increasing user comfort and reducing the risks of awkward wrist postures.
Over a period of six months, the research team closely analyzed how the subjects used their keyboards, including how much force they exerted on the keys with their fingers. The team also did video and three-dimensional motion analysis of the volunteers working at their computers. The results showed for the first time that keyboards specifically designed to lessen pressure on wrists can relieve the symptoms of WRMSDs and promote recovery. What's more, many of the alternative keyboards did not impair productivity and were relatively easy to learn.
The test subjects also completed a questionnaire on supervisor and coworker support and conflict. The data affirmed preliminary findings that the effectiveness of ergonomic interventions can be reduced in a stressful working situation.
The study, says Burastero, should have a "significant impact" by changing the way keyboards are designed and providing safety and health professionals with a greater understanding of the role of keyboards in WRMSDs. "There had been a lot of anecdotal evidence, but until now no one had systematically looked at how people actually work with keyboards or at the long-term effects," he says.
Livermore ergonomics experts caution that keyboards are only one factor associated with WRMSDs. For example, chairs, desks, terminals, and lighting conditions also play roles. So do pointing devices such as mice and trackballs, which the research team is planning to investigate in depth. At the very least, says Burastero, Lawrence Livermore can provide a knowledgeable perspective to manufacturers, clinicians, and workers everywhere. |