Drivers and passengers who don't wear their seatbelts thinking that the airbags in the car will protect them in the event of a crash, are at higher risk of cervical spine (neck) fractures and other spinal cord injuries, says a study by University of Pittsburgh researchers.
According to Dr. William F. Donaldson III of University of Pittsburgh and colleagues, airbags should be used with seatbelts to avoid such fractures and injuries.
"Airbags should be used in conjunction with seatbelts to minimize the risk of cervical spine fractures and spinal cord injuries associated with motor vehicle crashes," he said.
The researchers used a Pennsylvania trauma database and dentified crashes resulting in injuries to drivers and front-seat passengers from 1990 to 2002.
In the study, approximately 12,700 patients with spinal injuries were involved - 8,500 drivers and 4,200 passengers. Of these, 5,500 patients had fractures of the cervical spine.
Researchers found that the rate of cervical spine fractures was 54 percent in drivers using an airbag only, as compared to 42 percent for drivers using both an airbag and seatbelt.
After taking into account other factors, the relative risk of cervical spine fracture was 70 percent higher for drivers using an airbag without a seatbelt, as compared to drivers using both protective devices.
This was even greater than the 32 percent increase in cervical fracture risk for drivers using neither an airbag nor seatbelts.
In case of passengers, researchers found that the risk of cervical fracture plus spinal cord injury was nearly seven times higher for those using an airbag without seatbelts (compared to both protective devices.
In case of both drivers and passengers, women were about half as likely as men to be injured using an airbag alone.
It was also found that after reaching the trauma center, patients who used an airbag only had higher injury severity scores. They also spent more time in the intensive care unit and more total time in the hospital.
The findings showed that drivers and passengers who use airbags without seatbelts have a higher rate of cervical spine fractures, with or without spinal cord injury, and have more severe injuries in general.
The overall difference in injury severity likely reflects additional injuries to the chest, abdomen, and head.
"Use of seatbelt in conjunction with the airbag and maintaining at least 10 inches between the steering column and the sternum may decrease injury severity and rate of airbag induced cervical spine and spinal cord injuries," Dr. Donaldson and colleagues said.
The study is published in the March 15 issue of Spine.