Ergonomic chair design for school computer laboratories in theCape Metropole, Western Cape, South Africa

[摘要] ENGLISH SUMMARY : Background: Computers have become increasingly accessible in developing countries. Suchincreased computer usage is also noted in the Western Cape, South Africa. Prolonged posture whilst using computers and a learner‐chair mismatch is associated with spinal pain in adolescents. In South Africa, the prevalence of spinal pain among high school learners has been reported as being about 70%. Consideration of learner anthropometrics and school furniture design is essential to evolving strategies to be adopted to promote adolescent spinal health.Aim: The aim of this project is to determine whether the school computer laboratory chair or a commercially‐available chair matches the anthropometric profile of high school learners and, if not, to develop and test a prototype chair that will also facilitate postural changes, whilst the sitter is using a desktop computer.Methods: This study consisted of two phases. Phase one dealt with the anthropometric match of the learners to their school chair and to commercially‐available chairs. The following body dimensions were measured: stature; popliteal height (PH); buttock‐topopliteallength (BPL) and hip width (HW). These body dimensions were matched with thecorresponding chair seat dimensions; and height, depth and width, using standardmatching criteria. During Phase two, a prototype chair was designed according to the anthropometric profile of the learners concerned. The chair's ability to reduce static sitting postures by facilitating postural changes in sitters whilst they are seated at a desktop computer was evaluated. The three‐dimensional (3D) sitting posture of twelve learners was evaluated while they were sitting on the school and the prototype chairs. Theanthropometric and 3D data were analysed using descriptive statistics, including means (and standard deviations), medians (and interquartile ranges (IQR)) and ratios. Todetermine the difference in the number of postural changes between chairs, the Wilcoxon match pair test was used.Results: The sample consisted of 689 male and female learners aged 13 to 18 years, for the anthropometric study (phase 1). Of the learners, 65% to 80% did not match the school chairs' dimensions. Five commercial chairs offered a good match for the seat height, butneither the seat depth nor the seat width matched 50% of the learners. The prototype chair matched 97% for height, 65% for depth and 60% for seat width. The prototype chair was associated with more postural changes in the frontal and transverse planes for the pelvis (ρ <0.05).Conclusions: This thesis is the first to report on the lower body anthropometric size of high school learners in the Cape Metropole area, Western Cape, South Africa. Neither the school computer laboratory chair nor commercially‐available adjustable computer chairs offered an acceptable fit for the anthropometric profile of the learners. The prototype'Dynamic chair was consequently developed and provided the best match for the anthropometric profile. The prototype chair was also associated with an increased number of postural changes, particularly of the pelvis. The promising results obtained warrant further exploration of the prototype chair to determine the effect on the musculoskeletal pain experienced by school learners in South Africa.

[发布机构] Stellenbosch University