Rear-Impact Neck Protection Devices for Adult Wheelchair Users
By Simms, Ciaran K.; Madden, Brian; FitzPatrick, David; Tiernan, John; Journal of Rehabilitation Research and Development, Vol. 46, No. 4, pp. 499-514Publication Date: 2009
Study undertaken to develop a head restraint to protect adult wheelchair users from rear-impact injury while traveling in a vehicle. For the purpose of assessing injury risk, three rear-impact sled tests were conducted at 16 kilometers per hour with the Biofidelic Rear Impact Dummy II seated in a rigid wheelchair with no head restraint. Results showed that Abbreviated Injury scale-score 1 neck injury risk, evaluated with the neck injury criterion (NIC) and Nkm criterion, was substantially above proposed threshold levels. A prototype wheelchair head restraint was developed based on the principle of reducing the bending moment in its vertical upright stalk as well as the risk of pullout forces separating the head restraint from the seat back. The prototype was tested together with the commercially available Rolko head restraint under the previous experimental conditions. Both restraints reduced the injury scores substantially. NIC test scores for the head restraints ranged from an approximate 20 to 30 percent chance of neck injury symptoms lasting more than one month, compared with test scores for no head restraints that showed an approximate 95 percent chance of neck injury. Corresponding Nkm scores for the restraints showed a near 5 percent chance of neck injury, compared with no head restraint revealing a 45 percent chance of injury. Both head restraints performed similarly, but the Rolko was found to be lighter and more easily attached and removed. Preliminary results also showed that the horizontal gap between the head and the wheelchair head-restraint cushion should be as small as possible.
Published by:
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/09/46/4/simms.html

