title: Rear-impact neck protection devices for adult wheelchair users.
abstract: Many wheelchair users remain in their wheelchairs during transit. Safety research for wheelchair users has focused mainly on frontal impact. However, although they are generally less severe, rear-impact injuries are expensive and difficult to treat and whiplash injury protection for adult wheelchair users remains poorly understood. In this article, 10 g (16 km/h) rear-impact sled tests conducted with the Biofidelic Rear Impact Dummy II or BioRID-II (Denton ATD Inc and Chalmers University of Technology; Gothenburg, Sweden) seated in a rigid wheelchair with no head restraint showed that Abbreviated Injury Scale-score 1 neck injury risk evaluated with the neck injury criterion (NIC) and Nkm criterion is substantially above proposed threshold levels. A prototype wheelchair head restraint was developed and tested together with an existing commercial head restraint (Rolko; Borgholzhausen, Germany) in the same 10 g (16 km/h) rear impact. Both head restraints reduced the injury scores substantially. NIC test scores for the head restraints with no gap ranged from 18 to 24 (approximately 20%-30% chance of neck injury symptoms of duration >1 month) compared with test scores for no head restraints that ranged from 34 to 37 (approximately 95% chance of neck injury). The corresponding extension-posterior Nkm scores with no gap ranged from 0.30 to 0.35 (approximately 5% chance of neck injury) compared with no head restraint of 1.16 (approximately 45% chance of neck injury symptoms). However, the number of sled tests performed was small (three with no head restraint and six with a head restraint), and these results should be considered mainly trends. Preliminary results also showed that the horizontal gap between the head and the wheelchair head-restraint cushion should be as small possible.
authors.affiliation: Trinity Centre for Bioengineering, Trinity College, College Green, Dublin 2, Ireland. csimms@tcd.ie
authors.forename: Ciaran K
authors.initials: CK
authors.lastname: Simms
authors.forename: Brian
authors.initials: B
authors.lastname: Madden
authors.forename: David
authors.initials: D
authors.lastname: Fitzpatrick
authors.forename: John
authors.initials: J
authors.lastname: Tiernan
mesh_terms: D000328:Adult; D004867:Equipment Design; D019416:Head Movements; D006801:Humans; D008348:Manikins; D011482:Protective Devices; D016059:Range of Motion, Articular; D012149:Restraint, Physical; D012307:Risk Factors; D016474:Weight-Bearing; D014910:Wheelchairs; D014911:Whiplash Injuries / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control*