Relevance of adding a triangular dynamic cushion on a traditional chair: A 3D-analysis of seated schoolchildren

A systematic review of research on sitting and working furniture ergonomic from 2012 to 2022: Analysis of assessment approaches

“…Based on a systematic review of the literature, some studies may offer different technical approaches to the ergonomics of furniture as well as new research ideas, such as the combination of Six Sigma Methods and Ergonomics: tandem ESSM methods are successful and effectively deployed [ 38 ]; 3D analysis of sitting posture [ 61 ]; 3D assessment is very accurate with a motion detection threshold of ∼1° [ 75 ], etc. These methods could currently fill a research gap in the area of furniture ergonomics.…”

“…The method of video recording analysis should be researched further. Fettweis et al [ 61 ] Quantitative 3D analysis, Electromyography (EMG), Dynamographic analysis Objective On-site measurements Statistical software “R”. (Version 3.3.0) Cushions can help prevent low back pain by improving the torso-thigh angle, lumbar lordosis, anterior pelvic tilt, and foot-to-floor supports.…”

Application of mismatch equations in dynamic seating designs

“…In 1981, Mandal recommended a position with a 135 • -trunk-thigh angle to favor physiological lumbar lordosis (Mandal, 1981), requiring furniture designers to increase either seat height or slope. However, Mandal did not take dynamism into account (Fettweis et al, 2017): even a static perching posture, while encouraging an erect spine posture with forward sloping chairs, has setbacks, such as increased pressure distribution towards the feet with slopes over 15 • (Corlett and Gregg, 1994;Fettweis et al, 2017); higher knee and ankle extensor activity (Hamaoui et al, 2016); and undesirable lower limb muscle overactivity to prevent the body from sliding. To best mitigate these issues, a saddle chair with an overall height increase has been consistently proven to be both biomechanically better and preferred by users (Bendix, 1994;Bendix and Bridger, 2004;Corlett, 2009Corlett, , 1999Mandal, 1994bMandal, , 1994a1991, 1981Noro et al, 2012).…”

“…Based on the above, "new" fundamental design principles to bear under the framework of Dynamic Sitting, i.e., posture changes among sitting, standing, and half-standing positions, also known as semi-sitting or perching, should be included in office settings (Bendix and Bridger, 2004). Several documented principles have addressed Dynamic Sitting, and conclude that height-adjustable desks, a high saddle chair or tilting seat pans, all of them allowing the feet to be placed on the floor, promote higher user comfort levels (Fettweis et al, 2017;Mandal, 1994a). While the design of chair and desk sitting equipment generally imposes specific criteria, these are often extracted from laboratory settings; as such, the resulting sitting design testing equations used to test or match a specific design to an intended population do not generally take posture variability into account (Nadadur and Parkinson, 2013;Pheasant and Haslegrave, 2006).…”

Finite element study of sitting configurations to reduce sacroiliac joint loads

“…Instead triangular cushions can help to achieve a larger trunk-thigh angle of 120 • , closer to the 'ideal position' of 135 • (11,13,14). This position of seat pan declination increases the relative posterior tilt of the trunk with respect to the thigh.…”