HAZARDS AND EFFECTS OF EXPOSURE TO RISK FACTORS FOR THE DEVELOPMENT OF THE SYMPTOMS OF MUSCULOSKELETAL DISORDERS

Musculoskeletal disorders (MSDs) are considered to be one of the most common health problems in the European Union and an important cause of absences from work (www.eurofound.europa.eu; European Agency for Health and Safety at Work).

In European Union countries, research on working conditions and occupational diseases is carried out every few years. Figure 1 shows the percentage of workers complaining about different types of disorders, also broken down by the age of the worker.

Fig. 1. Incidence of musculoskeletal disorders in workers in the European Union (based on the European Work Condition Survey), taking into account the gender and age of the workers

MSDs are assumed to be the consequence of injuries associated with tissue damage. A injury is sudden, but may be associated with previous lesions in tissues caused by overload. Musculoskeletal overload lesions in motion organs may occur in muscles, tendons, cartilages and joint capsules as well as ligaments and bones. The most important common symptom of these lesions is pain and subsequently functional disorder of the overloaded tissues. Sometimes, after healing the effects of injury, different types of dysfunctions may occur at a given site.

The pathophysiology and sources of development of MSDs have not yet been fully explained. It appears that the MSDs may be due to numerous reasons which thus create an inappropriate margin between the requirements resulting from the work and the worker’s capabilities resulting from his/her individual characteristics. The site of the overload lesions and the resulting MSDs are often linked to the type of tasks performed in the workplace. It is assumed that MSDs result from the cumulative impact of a long-term load with different intensity, and professional work is considered the main source of overloads and development of MSDs (Figure 2). It is generally accepted that the site of the overload lesions and the resulting MSDs depend on the tasks performed in the workplace. The factor increasing the overload leading to the development of musculoskeletal disorders is the lack of ergonomic solutions in workplaces

Fig. 2. The relationship between the presence of musculoskeletal disorders and the job position and work process.

Musculoskeletal disorders are a broad term concerning mainly pain disorders (Figure 3). Overload syndromes, i.e. diagnosed diseases, are less frequent. Certain diagnosed diseases are classified as occupational diseases; as defined by the World Health Organization (WHO), an occupational disease is one for which there is a direct relationship between the factor of the work environment causing it and the disease itself (WHO, 1985). Whereas para-occupational diseases are understood as diseases with complex aetiology, in the development of which working conditions are one of several causal factors, but the share of these factors is not dominant. This means that a para-occupational disease may be caused partly by the working conditions, however non-occupational factors and individual factors also constitute risk factors for the development of such a disease.

Fig. 3. Qualification of musculoskeletal disorders.