Isolated vehicle rollover is not an independent predictor of trauma injury severity

The objective of this study was to determine if vehicle rollover in a motor vehicle crash is an independent predictor of major injury.

A retrospective cohort study of all patients injured in motor vehicle crashes presenting to a major trauma center between July 2012 and June 2016 was conducted. Crashes were classified into groups: non-rollover, isolated rollover (without other mechanisms of injury), or mixed-mechanism rollover (with other mechanisms of injury). Associations between rollover group, other covariates (entrapment, encapsulation, ejection, death on scene, high speed, seat belt usage, airbag deployment, trauma team activation), and major injury (injury severity score >15, major surgery, intensive care unit admission, or in-hospital death) were tested using binary logistic regression models. Vehicle rollover was categorized either as "present" or "absent" on 1 model or as either "none," "isolated," or "mixed mechanism" in the other.

In 2446 motor vehicle crashes, there were 423 rollovers (196 isolated, 227 mixed mechanisms). Compared with crashes without rollovers, the prevalence of patients with major injury was lower in crashes with isolated rollovers and higher in crashes with mixed-mechanism rollovers (13.8% vs 9.5% vs 27.5%, respectively; P < 0.001). Rollover (present vs absent) was not an independent predictor of major injury (odds ratio [OR], 1.10; 95% confidence interval [CI], 0.78-1.53). Patients in crashes with mixed-mechanism but not isolated rollovers had increased odds (OR, 2.04; 95% CI, 1.41-2.96) of major injury compared with patients from crashes without rollovers.

Patients from crashes with isolated vehicle rollovers may not need to be transported to a trauma center as they carry a lower risk of injury.