The impact of helmet use on outcomes after a motorcycle crash.

BACKGROUND: Helmet use in a motorcycle collision has been shown to reduce head injury and death. Its protective effect on the cervical spine (C-spine), however, remains unclear. The objective of this study was to explore the relationship between helmet use and C-spine injuries.

METHOD: Retrospective National Trauma Data Bank (NTDB) study. All motorcycle collisions between 2007 and 2014 involving either a driver or passenger were included. Data collected included demographics, vital signs, Abbreviated Injury Scale (AIS), Injury Severity Score (ISS) and specific injuries. The primary outcome was the prevalence of C-spine injuries. Secondary outcomes included were overall mortality, ventilation days, intensive care unit length of stay (LOS), total hospital LOS, and in-hospital complications.

RESULTS: A total of 270,525 patients were included. Helmets were worn by 57.6% of motorcyclists. The non-helmeted group was found to have a higher incidence of head injury with head AIS>2 (27.6% vs 14.8%, p<0.001). Univariate analysis showed a higher prevalence of C-spine injuries in the non-helmeted group (10.4% vs 9.4%, p<0.001), with a higher proportion of severe C-spine injuries with AIS>2 (3.2% vs 2.6%, p<0.001). Additionally, traumatic brain injury (TBI) was found to be two times higher in the non-helmeted group (20.7% vs 10.9%, p<0.001). Multiple logistic regression showed helmet use to be an independent protective factor against mortality (OR=0.832, 95% CI 0.781-0.887, p<0.001). Although statistically significant in univariate analysis, helmet use was not associated with C-spine injuries after adjusting for relevant covariates. However, helmet use reduced the risk of severe head injuries by almost 50% (OR=0.488, 95% CI 0.475-0.500, p<0.001).

CONCLUSIONS: Helmet use reduces the risk of head injury and death among motorcyclists; however, no association with C-spine injuries could be detected.