Pre-conference Workshops & Tutorials

The following Pre Conference events are offered at PREMUS2004

Workshop # 1
Physical exposure assessment of hand acitvities
Stephen Bao, Ph.D.

Musculoskeletal injuries and illnesses account for a tremendous amount of lost workdays and cost to industry of many industrial countries. In the United States, the Bureau of Labor Statistics (BLS) reported 308,000 cases of illness due to repeated trauma in 1995 that accounted for 60 percent of all work-related recorded illnesses. Intensive hand activities have been linked to some work-related upper extremity disorders such as: epicondylitis, carpal tunnel syndrome and hand/wrist tendinitis, etc. Reducing the exposure to the risk factors involved in the intensive hand activities is practiced at workplaces to reduce work-related musculoskeletal disorders. Quantification of physical exposures of these hand activities would help the practitioners to determine the hazard level and make decisions in terms of introducing solutions. This workshop will help the participants to achieve this goal. Participants to this workshop will be able to learn hands-on skills in performing ergonomic exposure assessment of hand activities. Participants to previous sessions of this workshop have indicated that they have gained the skills after the workshop. Several widely used methods will be discussed, including elements of Washington State's Ergonomics Rule1 relating to hand forces and hand/wrist repetitive motions, the ACGIH's Hand Activity Level TLV, and the Strain Index method. These methods will be applied to real life cases. The participants will get opportunities in using them and compare results obtained from the different methods. This workshop will benefit those who practice ergonomics in workplaces. Safety and health practitioners, members of joint health and safety committees, safety and health managers, ergonomists, and students who plan to do job assessment in the future will benefit from this workshop most. Previous knowledge of job analysis and physical demand analysis is not required, but will certainly help in understanding the assessment processes better.

Workshop # 2
Occupational Health Prevention of Musculo-Skeletal Disorders: The German Experience
Prof. Bernd Hartmann

Muskuloskeletale disorders are caused or strengthened substantially by vocational activities. The most effective possibilities of their prevention exist at the same time in the vocational sphere. And rehablitation-medical components according to industrial medicine and ergonomic of prevention are therefore interconnected. The Workshop has the goal of presenting concepts of prevention concerning company doctors in Germany. The presented programs and activities developed in the co-operation of occupational accident insurances ("Berufsgenossenschaften"), company doctors, national institutes for industrial safety and old age pension insurances:

• The initial position is represented on the basis of operating near epidemiological and ergonomic investigations on a broad database.
• For prevention concerning company doctors a medical analyzer is presented, in which the evaluation of the functions of the muscle skeleton system has the priority before the orthopedists diffential diagnosis.
• The application of prevention concerning company doctors recommended due to the evaluation of the load manipulation, the work in different obligation attitudes, that repetitive hand arm load and the effect of vibrations.
• Two rehablitation programs for the preservation of the earning power as well as for the reintegration with muscle skeleton disorders are presented.
• Finally the action framework of the company doctor within the range of the ergonomics is discussed.

The Workshop addresses itself to the work medical profession and their co-operation partner to improve the operational prevention from muscle skeleton illnesses to.

Workshop # 3
A tutorial on Surface Electromyography
Hermie Hermens, Ph.D. and Miriam Hutten-Vollenbroek, Ph. D.
Roessingh Research and Development, Enschede, The Netherlands

Surface ElectroMyography (SEMG) is a powerful tool to assess the neuromuscular function(ing). In fact, it is at present the only tool to study how (ab)normal movements are generated and to what extend a muscle is loaded. During the past years, both the technology to record the SEMG, as well as our understanding of the interpretation of the SEMG has increased considerably. This has enabled the development of recommendations for recording and analysis of the SEMG at a European level (E.C. project SENIAM) that is gaining now worldwide acceptance. This allows reproducible measurements, a useful exchange of data and a common interpretation. The objective of this tutorial is to provide a good practical but scientificically based understanding of how the SEMG should be recorded, analyzed and interpreted. Topics that will be addressed during this tutorial are:

• Recommendations and pitfalls for recording the SEMG signal
• Relevant backgrounds for a proper interpretation of the SEMG signal and its parameters
• Using the SEMG in occupational health studies; reliability and sensitivity of amplitude (e.g. RMS) and timing (e.g. relative rest time) parameters
• The use of normalisation procedures to decrease intra and inter subject variability
• Muscle activation in chronic pain and the use of myofeedback in neck/shoulder pain (with demonstration)
• New emerging SEMG techniques

Workshop # 4
Workshop on Mechanisms of Musculoskeletal Disorders
Shrawan Kumar, Ph.D.
Ergonomics Research Laboratory, Department of Physical Therapy, University of Alberta, Edmonton

The evidence published in the literature linking the risk factors for the precipitation of musculoskeletal injuries at work allow us to deduce four theories for these afflictions. Central to all theories is the presupposition that all occupational musculoskeletal injuries are biomechanical in nature. Disruption of mechanical order of a biological system is dependent on the individual components and their mechanical properties. These common denominators will be causally affected by the individual's genetic endowment, morphological characteristics and psychological makeup, and the occupational biomechanical hazards. This phenomenon is explained by the Multivariate Interactive Theory. Cumulative Load Theory suggests a threshold range of load and repetition product beyond which injury precipitates, as all material substances have a finite life for their forms. Differential Fatigue Theory accounts for unbalanced and asymmetric occupational activities creating differential fatigue and thereby a kinetic and kinematic imbalance resulting in injury precipitation. Finally the Overexertion Theory claims that exertion exceeding the tolerance limit precipitation occupational musculoskeletal injury. It is also suggested that while these theories may explain the immediate mechanism of precipitation of injuries, they all operate simultaneously and interact to modulate injuries to varying degrees in different cases. The foregoing theories emphasize the work relatedness of the occupational injuries. Thus the variables of force, effective exposure in time domain, and motion of exertions in space constitute the primary physical stressors. It is therefore possible to determine these variables quantitatively and establish their relative weighting. Through a mathematical model (Kumar, 1994), a quantitative assessment of risk of injury can be derived. By manipulating these variables within the context of work a meaningful control can be realized.
Objective: Attendees of this workshop will be provided with a unique perspective on causation of occupational musculoskeletal injuries, and methods of assessing risk. The later will assist in control of the problem.
Audience: This workshop is designed for anyone in causation and control of musculoskeletal injuries in the workplace.

Workshop # 5
Designing and Running Effective Ergonomic Intervention Studies (pdf)
Patrick Neumann and Prof. Jorgen Winkel

This workshop will present contrasting views and foster dialogue in three key areas:

1. Design and implementation of effective ergonomic interventions
2. Design of high quality intervention research projects
3. Strategies and methods in evaluation of ergonomics interventions

The target participant group would be researchers (and interested practitioners) focusing on prevention of musculoskeletal disorders in the workplace. Noted researchers will be invited to present their views on key studies as a basis for further discussion by participants. This workshop will try to explore the common ground between the ‘Random Control Trial’ and the ‘Action Research Case Study’ traditions, which seem to pose paradigmatically different approaches to ergonomics intervention research. We will adopt a systems approach to focus discussion and analysis inside the workshop.
Organisers would summarise workshop results and commentary for distribution, ideally to a scientific journal.

Questions to be addressed by participants in the workshop include:

1. ERGONOMIC INTERVENTION DESIGN
- What is the intervention?
- Where do we intervene (what level)?
- What research models (researcher - company relationships) are best?

2. RESEARCH DESIGN
- What is the research question? What are you investigating?
- Who is the research for? Audience? Desired effect?
- How do you investigate the effects of the intervention?
- What is good ergonomics research? Study designs?

3. EVALUATION METHODS IN ERGONOMIC INTERVENTION RESEARCH
- What evaluation strategies are best? What indicators should we use?
- Measurement approaches and considerations?
- Qualitative vs. quantitative methods?
- What methods are being used? Advantages & disadvantages?

The Workshop Team:

• Dr. Donald Cole – Sr. Scientist, Institute for Work & Health; and Professor, University of Toronto, Department of Public Health, Toronto Canada
• Dr. Ole Broberg – Professor, Department of Manufacturing Engineering and Management, Danish Technical University, Copenhagen, Denmark.
• Dr. Jan Dul – Professor of Ergonomics Management., Erasmus University, Rotterdam, The Netherlands.
• Dr. Richard Wells – Professor, Department of Kinesiology, University of Waterloo; and Director, Action Centre for the Prevention of Work-related Musculoskeletal Disorders, Waterloo, Canada.
• Dr. Hilkka Riihimäki - Director, Epidemiology and Biostatistics, Finnish National Institute for Working Life.
• Dr. Peter Vink – TNO Work and Employment, The Netherlands, & Professor in Participatory Ergonomics, Faculty of Design, Construction and Production, Delft University of Technology, Delft, The Netherlands

For questions concerning the pre-conference events please contact us.

Peter Schenk
Swiss Federal Institute of Technology
Institute of Hygiene and Applied Physiology
Clausiusstr. 25
8092 Zurich, Switzerland