Wheelchair Users Seated in Wheelchairs While Traveling May Be At Increased Risk of Injury in Motor Vehicle Crashes, Say Pitt Researchers

PITTSBURGH, January 9, 2001 — Continued advances in wheelchair mobility, driving adaptations and vehicle modifications, along with the passage of the 1990 Americans with Disabilities Act, have been providing persons who use wheelchairs improved access to transportation, via both public transportation and personal vehicles. Many wheelchair users are unable to transfer to a vehicle seat and remain seated in their wheelchairs while traveling. However, along with increased travel miles and enhanced access may come an increased risk of injury.

According to researchers at the University of Pittsburgh School of Health and Rehabilitation Sciences (SHRS), when used as motor vehicle seats, commercially available wheelchairs that are not specifically designed for transportation may not provide adequate occupant protection in a crash. Vehicle-mounted occupant restraint systems, which fail to provide proper belt fit, may further increase injury risk by failing to protect the wheelchair user in a crash. These findings are published in the current issue of the Journal of Rehabilitation Research and Development.

Gina Bertocci, Ph.D., P.E., and a team of SHRS researchers evaluated, in four different studies, the crashworthiness of wheelchair seating and wheelchair occupant restraint systems. In almost all of the studies, the researchers found that standard wheelchair seating components failed to withstand simulated crashes, placing wheelchair users – both adults and children -- at a greater risk of injury.

“Wheelchair-seated travelers are unable to benefit from standard vehicle safety features because wheelchairs are not designed with crash safety as a primary function,” reports Dr. Bertocci. “Furthermore, occupant restraint systems used by vehicle-seated occupants have been designed to accommodate and provide effective protection to able-bodied occupants. Constraints posed by wheelchair components such as armrests may lead to poorly positioned lap and shoulder belts, which have been documented as a source of belt-related injury.”

In two of the studies -- one that evaluated the crashworthiness of commercially available wheelchair back supports and one that assessed the effectiveness of wheelchair occupant restraint systems in a frontal crash -- the components failed to withstand a simulated crash or failed to adequately protect the wheelchair user. For instance, in the study evaluating occupant restraints, researchers found that standard shoulder belt anchorage locations can lead to the belt passing over the face or upper neck of children and smaller wheelchair occupants, rendering the restraints useless and even dangerous. In another of the studies, Dr. Bertocci and her colleagues utilized computer simulations to provide design criteria to aid manufacturers in the development of transport-safe wheelchairs.

“In most cases, typical seat and wheel assemblies will not sustain a crash well enough to maintain a person in the position necessary for effective restraint,” said Douglas Hobson, Ph.D., associate professor, SHRS, who provides a guest editorial in the journal. “Accessories, such as seat inserts, position supports and tray-mounted devices are often added to the wheelchair after they leave the manufacturer, and are not designed with crash injury prevention as a goal. Many wheelchair frame designs lack the necessary strength for attachment of the tie-down straps required to secure the wheelchair to the vehicle.”

“Substantial research is being conducted to improve the safety of vehicle seats and to improve protection for the occupant. Manufacturers of automotive seats are now required to perform extensive testing to ensure that vehicles comply with government crashworthiness standards,” said Bertocci. “Our studies further prove that the stringent standards that apply to automotive seat manufacturers need to be transferred to the wheelchair transportation industry.”

Other researchers involved in the project include Stephanie Szobota, B.S.; DongRan Ha, B.S.; Linda van Roosmalen, M.S.; Patricia Karg, M.S.; and Ernest Deemer, B.S.