SATURDAY, Oct. 23 (HealthDay News) -- Airbags greatly reduce the risk of kidney injury in car crashes, according to a new study.

Front-impact airbags were associated with a 45.3 percent reduced risk of kidney injury, while side-impact airbags were associated with a 52.8 percent reduced risk, compared to crash patients from cars that did not have air bags, researchers found.

The findings came from an analysis of 2,864 records in the U.S. Crash Injury Research and Engineering database from 1996 to September 2008. Researchers identified 139 kidney injuries suffered by occupants of vehicles with and without air bags.

The study was published in a recent issue of the Journal of the American College of Surgeons.

"The sharp reduction in the rate of kidney injury was surprising because airbags are primarily designed to protect the head and spine. These findings warrant additional investigation into the role airbags could play in protecting the kidney and other organs during a crash," study author Dr. Thomas G. Smith III, an assistant professor of urology in the department of surgery at University of Texas Medical School at Houston, said in news release from the journal's publisher.

In crashes where people suffered kidney injury, 54.7 percent were front-impact and 45.3 percent were side-impact collisions. Looking only at front-impact crashes, the researchers noted that nearly three-quarters involved a driver-side airbag and only 16.6 percent involved a passenger-side airbag. In the side-impact crashes, less than one-third of occupants had a side-impact airbag.

Vehicle crashes are the most common cause of blunt force trauma to the kidneys, accounting for about half to two-thirds of all such injuries, according to the researchers. This is the first study to evaluate the protective effects of airbags on kidneys.

More information

The American Urological Association Foundation has more about kidney trauma.