Occupant and Crash Characteristics of Elderly Subjects With Thoracic and Lumbar Spine Injuries After Motor Vehicle Collisions.

STUDY DESIGN Retrospective study of a prospectively gathered database. OBJECTIVE To investigate the incidence and pattern of thoracic and lumbar (T and L) spine injuries among elderly subjects involved in motor vehicle collision (MVC). SUMMARY OF BACKGROUND DATA Adults age 65 and older currently constitute more than 16% of all licensed drivers. Despite driving less than the young, older drivers are involved in a higher proportion of crashes. Notwithstanding the safety features in modern vehicles, 15.8% to 51% of all T and L spine injuries result from MVCs. METHODS Crash Injury Research and Engineering Network database is a prospectively maintained, multicentered database that enrolls MVC occupants with moderate-to-severe injuries. It was queried for T and L spine injuries in subjects 65 and older. 142 Crash Injury Research and Engineering Network files for all elderly individuals were reviewed for demographic, injury, and crash data. Each occupant's T and L injury was categorized using a modified Denis classification. RESULTS Of 661 elderly subjects, 142 (21.48%) sustained T and L spine injuries. Of the 102 major injuries, there were 63 compression, 20 burst and 12 extension fractures. Seatbelt use predisposed elderly subjects to compression and burst fractures, whereas seatbelt and airbag use predisposed to burst fractures. Deployment of airbags without seatbelt use appeared to predispose elderly subjects to neurological injury, higher Injury Severity Score, and higher mortality. Occupants using 3-point belts who had airbags deployed during the collision had the lowest rates of fatality and neurological injury. CONCLUSION T and L spine injuries in the elderly are not uncommon despite restraint use. Whereas seatbelts used alone and in conjunction with airbag deployment reduced fatalities and neurological injuries in the elderly, deployment of airbags in occupants without seatbelts predisposed to more severe injury.