TUESDAY, May 18 (HealthDayNews) -- Some bikers might think it's silly to wear a helmet while motorcycling, but statistics say otherwise.

Helmets saved the lives of about 692 motorcyclists in 2002, according to a study presented recently at the annual meeting of the American Association of Neurological Surgeons in Orlando, Fla.

Researchers also concluded that another 449 lives could have been saved if all motorcyclists wore helmets.

Head and cervical spine injuries are the leading cause of death and disability in motorcycle and all-terrain vehicle crashes. The study was done in response to recent research that indicated helmets might actually increase the risk of skull and spine injuries.

The doctors concluded the opposite was true after studying a decade's worth of documented ATV and motorcycle collisions in West Virginia. They focused specifically on riders under the age of 18.

"Helmets repeatedly have been shown to reduce the risk of head injury," study co-author Dr. Charles L. Rosen said in a prepared statement. "They reduce the incidence of skull base fractures and do not increase the risk of cervical spine injuries."

Twenty states now require that all motorcyclists wear helmets while on the road, while another 27 states have helmet laws covering riders under 18. Three states -- Colorado, Illinois and Iowa -- have no helmet requirements in place at this time.

More information

Here's where you can learn more about helmets and motorcycle safety.