title: The effect of a backrest and seatpan inclination on sitting discomfort and trunk muscle activation in subjects with extension-related low back pain.
abstract: Few studies have demonstrated that seating modifications reduce low back pain (LBP). One recent study found that a forward-inclined seatpan reduced low back discomfort (LBD), however this was only examined in people with flexion-related LBP. No study has yet investigated its effectiveness among people with extension-related LBP. This crossover study examined 12 subjects with extension-related LBP. Sitting discomfort and surface electromyography of three trunk muscles were recorded during a 10-minute typing task while sitting with two different seatpan inclinations, both with and without a backrest. LBD (p < 0.001) and overall body discomfort (OBD) (p = 0.016) were significantly greater on the forward-inclined seatpan. The backrest did not alter trunk muscle activation or sitting discomfort. The results demonstrate that in a specific subgroup of people with extension-related LBP, increasing forward seatpan inclination significantly increased LBD and OBD. Future research should consider matching ergonomics prescriptions according to the individual presentation of people with LBP.
authors.affiliation: a Department of Clinical Therapies, University of Limerick , Limerick , Ireland.
authors.forename: Máire
authors.initials: M
authors.lastname: Curran
authors.forename: Wim
authors.initials: W
authors.lastname: Dankaerts
authors.forename: Peter
authors.initials: P
authors.lastname: O'Sullivan
authors.forename: Leonard
authors.initials: L
authors.lastname: O'Sullivan
authors.forename: Kieran
authors.initials: K
authors.lastname: O'Sullivan
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004576:Electromyography; D006804:Ergonomics; D005260:Female; D006801:Humans; D007374:Interior Design and Furnishings; D017116:Low Back Pain / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D064170:Paraspinal Muscles / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D060726:Torso / Q000502:physiology
keywords: back pain; musculoskeletal disorders; office ergonomics; seating