Ergonomically designed kneeling chairs are they worth it? : Comparison of sagittal lumbar curvature in two different seating postures

摘要

General agreement among researchers suggests that poor seating posture may predispose individuals to developing low back pain. A variety of methods such as ergonomically designed chairs have been developed to assist people to maintain good posture and preserve the 'natural' lumbar curve. The aim of this study was to compare lumbar curvature on an ergonomically designed kneeling chair (EKC) with that on a standard computer chair (SCC), with reference to the standing lumbar curvature. The study used a repeated measures, within-subjects design. A convenience sample of twenty participants was recruited aged 18-35 (9 male and 11 female). Lumbar curvature was measured using the 'Middlesbrough Integrated Assessment System' (MIDAS) postural assessment tool in three different postures; sitting on a SCC, sitting on an EKC set at +20deg inclination and standing as the reference measurement. Results were analysed by a repeated measures one-way ANOVA (1 factor) with 3 levels followed by the Bonferroni post hoc test. The results showed a statistically significant difference between standing lumbar curvature and lumbar curvature produced by both of the chairs (p<0.05). There was also a statistically significant difference between the two seated positions (p<0.05). This study suggests that ergonomically designed kneeling chairs set at +20deg inclination do maintain standing lumbar curvature to a greater extent than sitting on a standard computer chair with an overall mean difference of 7.633deg. Further research with a greater number of subjects and on different chair designs is warranted.