Postural and articular stress at work
Almost half of all workers in France, or 8.4 million people, are exposed to at least one type of severe postural or articular stress, affecting more than two thirds of manual workers and one in five professionals. Postural stress can be divided into three main categories: tiring positions, strain-inducing postures and vertebral stress. The consequences for workers’ health depend on various factors, including the duration of exposure.
Postural and articular stress contribute to work-related strain, leading to wear and tear, premature ageing and illness. In particular, they can cause rheumatological problems in the limbs, which are more frequent in workers aged over 55 years. The consequences for workers’ health depend on various factors, including the length of time that they are exposed to this physical stress.
According to the SUMER 2003 survey, 32% of workers are exposed to tiring positions, such as frequent walking about, prolonged periods of standing and constant repetitive movements. Some 21% of workers are exposed to strain-inducing postures, such as kneeling, keeping their arms raised or crouching. A further 10% of workers are exposed to vertebral stress, maintaining their head and neck in the same position over a long period.
In all, 48% of workers, or 8.4 million people in France, are subject to at least one type of severe postural or articular stress: this total comprises more than 66% of manual workers, compared with slightly more than 20% of managerial workers.
Strain-inducing postures affect mainly manual workers, such as skilled tradespersons but also those employed (predominantly women) in sales jobs or domestic services. Tiring positions tend more to affect industrial manual workers. Female industrial manual workers are particularly affected by repetitive movements, while female professionals and managerial workers are prone to vertebral stress.
Three main categories
Severe postural stress can be grouped under three main categories:
- tiring positions, which include standing, walking about and repetitive movements for more than 20 hours a week;
- strain-inducing postures: kneeling, keeping arms raised, crouching or twisting the body for more than two hours a week;
- vertebral stress: maintaining the head and neck in a fixed position for more than 20 hours a week.
Almost one third of workers (32%) are exposed to tiring positions. It applies to almost twice as many workers aged under 25 years as older workers. Manufacturing workers are particularly affected, as are workers completing installation or repair tasks, cleaners, security guards and domestic workers.
Exposure to repetitive movements is often experienced alongside other risk factors for musculoskeletal disorders, including lack of autonomy at work or social support.
Repetitive movements mainly concern female manual workers: almost half of unqualified female workers are exposed to them, with the proportion rising even higher in some sectors, such as textiles.
Some 21% of workers are exposed to strain-inducing postures, working for more than two hours a week on their knees, keeping their arms raised, crouching down or twisting their body. Workers aged under 25 years are more prone to this than older workers, and men are more frequently affected than women. Strain-inducing postures are found particularly in the construction sector and in farming. They primarily affect male unskilled manual workers working in craft industries and women employed in domestic services.
Some 10% of workers maintain a fixed position of the head and neck for more than 20 hours a week; however, this proportion rises to as much as 25% in the financial services and textiles sectors.
This stress results mainly from working at a screen, generally at a computer: 75% of people adopting a fixed position of the head and neck work at a screen. Vertebral stress can also be associated with precision work or driving vehicles. It often accompanies repetitive work.
In general, women are more affected than men: 13% compared with 8%.
Cumulative risk factors
Postural and articular stress often result from a combination of strain-inducing postures and tiring positions. In addition, they are frequently associated with other risk factors, such as chemicals, extreme temperatures, and shift work.