Study Finds Using Airbags without Seatbelts Increases Injury Risk

In motor vehicle crashes resulting in airbag deployment, drivers and passengers who are not wearing seatbelts are at higher risk of cervical spine (neck) fractures and other spinal cord injuries, according to a study in the March 15 issue of Spine.

“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,” concludes the report by Dr. William F. Donaldson III of University of Pittsburgh and colleagues.

Using a Pennsylvania trauma database, the researchers identified crashes resulting in injuries to drivers and front-seat passengers from 1990 to 2002. The study included approximately 12,700 patients with spinal injuries—8,500 drivers and 4,200 passengers. Of these, 5,500 patients had fractures of the cervical spine.

The rate of cervical spine fractures was 54 percent in drivers using an airbag only, compared to 42 percent for drivers using both an airbag and seatbelt. With adjustment for other factors, the relative risk of cervical spine fracture was 70 percent higher for drivers using an airbag without a seatbelt, 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.

Among passengers, 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). For both drivers and passengers, women were about half as likely as men to be injured using an airbag alone.

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.

Automobile airbags have been highly successful in reducing injuries resulting from frontal collisions, reducing fatality rates by about 20 percent compared to seatbelts alone. Airbags were specifically designed to be used with seatbelts—serious injuries may result in victims who, because they are not properly restrained by seatbelts, are “out of position” when airbags deploy.

The new study provides new data on patterns of injury associated with incorrect airbag use.

The results show 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. Dr. Donaldson and colleagues write, “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.”

The journal Spine is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health, a provider of information and business intelligence for students, professionals, and institutions in medicine, nursing, allied health, pharmacy and the pharmaceutical industry.

Soource: Spine
www.spinejournal.com

Wolters Kluwer Health
www.WKHealth.com