Saskia Baltrusch

23 Chapter 2 1 Introduction Low-back pain, often termed a pandemic of the modern world, represents a large socio-economic burden. In the Global Burden of Disease Study from 2010 (Institute for Health Metrics and Evaluation), low-back pain was ranked highest in terms of years lived with disability. A variety of risk factors are believed to contribute to its incidence. Based on epidemiological research, three groups of risk factors for low-back pain have been identified: biomechanical, psychosocial and individual [1,2]. Many studies have investigated the effects of ergonomic interventions, aiming to reduce biomechanical risk factors [3,4]. However, ergonomic interventions are rather limited in their applicability, and reductions in back loading are attenuated by changes in lifting behavior [5,6]. With recent advances in robotic technologies, a shift has occurred towards external lifting devices that help the user to handle loads which are too heavy or require awkward lifting postures. Still, for handling loads within human capacity, users often prefer manual lifting, since external lifting devices are often slow to use and not always easily accessible [7]. This suggests that a wearable lifting device may be more usable. Several studies have found that wearing devices that passively support the user’s trunk reduces spinal loading during lifting, bending and static holding tasks [8-11]. Thus, developing such an exoskeleton might be helpful to reduce the risk of low-back pain. Besides biomechanical risks, psychosocial risk factors need to be considered in this context. Systematic reviews have revealed that psychological factors, such as stress, anxiety, pain behavior and somatization play a significant role in the transition from acute to chronic low-back pain [12,13]. Exposing individuals to negative psychosocial environments or demanding mental tasks during lifting also leads to increased spinal loading [14,15], indicating an interaction between biomechanical and psychological risk factors. Therefore, end-users’ perceptions of their environment, such as social, emotional and occupational aspects, need to be considered to truly minimize the risk of low-back pain [16]. O’Sullivan et al. (2011) [17] already emphasized the great need to better understand the complex mechanisms underlying low-back pain by using qualitative research methods, such as interviews and focus groups to listen 2