Bilateral project SLO-CRO: School Furniture as Risk Factor for Low Back Pain: Biomechanical Evaluation and Proposed Design Solutions (Bilateral project ARRS)

Duration of the project:

1.1.2020 – 31.12.2021

Lead partner:

Univerza na Primorskem, Fakulteta za vede o zdravju

Project partner:

University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture

Principal investigator/researcher:

prof. Nejc Šarabon (SICRIS, ResearchGate)

Team at UP FHS:

Assist. Nastja Podrekar (SICRIS, ResearchGate)
Assist. Prof. Matej Voglar (SICRIS, ResearchGate)
Assoc. Prof. David DeVallance (SICRIS, ResearchGate)


Lower back pain (LBP) is common among children and adolescents. Internal LBP risk factors can be age, gender and genetics. External risk factors can be lifestyle, wearing school bags and inappropriate school furniture design. Since students in the classroom spend most of their time in a seated position, school furniture could play a key role in maintaining and promoting correct posture, thereby reducing LBP. The goal of our project is to
comprehensively address the prevalence of LBP among children and adolescents. For this reason, we will carry out three studies: (i) measure the suitability of current school furniture in terms of active sitting positions of the body, (ii) measure biomechanical aspects of posture while sitting on a traditional school chair versus school chairs which improve “active sitting” and (iii) design and test advanced renewable composite furniture components embedded with bio-based carbonized sensor technology. MEASUREMENTS OF SUITABILITY OF CURRENT SCHOOL FURNITURE: Students who do not fit standard school furniture measurements have a greater likelihood of developing LBP, as the load on the musculoskeletal system increases. The incidence of LBP among students is unclear and insufficiently studied. Moreover, research results are often contradictory. Many studies have shown the inadequacy of school furniture according to the dimensions of students. Therefore, the purpose of our study is to measure the student-furniture mismatch among Slovene and Croatian pupils as well as observe and measure body activity during sitting on traditional and “active” school chairs. A cross-sectional study will involve a minimum of 70 pupils attending primary or secondary school (aged 9 to 20). An anthropometric set will be used to measure body dimensions, and the mismatch will be calculated using already established equations (Castellucci, Arezes & Molenbroek, 2014). Additionally, we will evaluate the incidence of LBP and lifestyle using validated questionnaires. The hypothesis is that currently designed school chairs have a stiff and strong construction and do not allow free movement of the child’s body while sitting, which creates pressure in the individual parts of the body and, consequently, influences development of LBP. MEASUREMENT OF BIOMECHANICAL ASPECTS WHEN SITTING ON THE SCHOOL CHAIR: Optimal design of school furniture, aimed at preventing LBP among students, is unknown. Research has shown that a positive inclination of the seat pan could reduce hip flexion and result in a more favorable position for the body. As a result, neutral position of the spine during sitting (i.e., the main precaution for the spine) could be established. In contrast, the seat of current school chairs is designed with a negative inclination. The optimal parameters of school tables are also not yet explained or sufficiently substantiated. In the laboratory study, we will evaluate new proposed design solutions for optimizing the school chair. Fifteen students (aged 9 to 20) will participate. We will focus on the ergonomic and biomechanical suitability of the seat pan and backrest, which will be evaluated using a pressure mapping system and the kinematic assessment of posture during sitting. The aim of the study is to find ergonomical and biomechanical design solutions for the optimization of school furniture that would reduce LBP among students.

DESIGN AND TESTING OF EMBEDDED RENEWABLE COMPOSITES FOR THE DESIGN AND MANUFACTURE OF SCHOOL FURNITURE: Utilization of renewable materials provides an environmentally conscious decision to develop novel composite materials with high functionality, as there exists potential to embed sensors produced from carbonized wood within composites to monitor pressure and temperature (Nan & DeVallance, 2017). This project aims to improve furniture comfort and reduce LBP by developing novel renewable composite furniture components with embedded bio-based, carbonized sensors. Data from the biomechanical measurement study will be utilized to develop the composites. At least 15 children and adolescents (aged 9 to 20) will participate in the laboratory study. Thermal resistance/absorption, inclusion of new functional wood-based materials and long-term durability will be included in the composite design. Thermal suitability of the new furniture components will then be evaluated using a thermal camera before and after 15 minutes of use. Harnessing this type of technology will allow for development of high performance, modified wood composite materials with integrated Information and Communication Technology (ICT). The resulting data will identify weaknesses in performance related characteristics in school furniture design and furniture components and assist in monitoring long term, in situ performance. The incidence of LBP among students is complex. School furniture is only one of many risk factors that can influence development of LBP. Therefore, optimal design of school furniture can only solve a limited part of the problem. Despite the limitations, results of this research will contribute an important understanding towards incidence of LBP among students, both in Slovene, Croatian and international environments. The results obtained will provide suggestions for improving the design of school chairs with interdisciplinary cooperation of all researchers and their areas.

References: Castellucci, H. I., Arezes, P. M., & Molenbroek, J. F. M. (2014). Applying different equations to evaluate the level of mismatch between students and school furniture. Applied Ergonomics, 45(4), 1123– 1132. Nan, N., & DeVallance, D. B. (2017).

Development of poly(vinyl alcohol)/wood-derived biochar composites for use in pressure sensor applications. Journal of Materials Science, 52(13), 8247–8257. 

The authors acknowledge the project “BI-HR/20-21-014 School Furniture as Risk Factor for Low Back Pain: Biomechanical Evaluation and Proposed Design Solutions is finacially supported by the Slovenian Research Agency.