Severity and predictors of head injury due to bicycle accidents in Western Australia

Background Head and face injuries are the second most frequently reported injuries among bicyclists. Recently, helmet usage has increased, and in some countries, helmet laws have been introduced. However, subsequent changes in the incidence and severity of traumatic brain injury (TBI) are unknown, and data on neurosurgical interventions are lacking. Therefore, we analyzed a cohort of bicyclists with TBI, in a state with an enforced helmet law, and compared our results with the available literature. Methods Patient data of bicycle accidents that occurred between January 2008 and January 2015 were extracted from the state trauma registry, and the corresponding patient files and CT scans were comprehensively reviewed. Results Of the 1019 patients admitted due to bicycle accidents, 187 patients suffered from TBI. Most cases were mild; however, 72 involved intracranial hemorrhages. Of the TBI patients, 113 were wearing helmets. CT scans were performed on 168 TBI patients, 120 of whom had a Rotterdam CT score of 1, with no difference between helmeted and non-helmeted patients. Open head injury (p < 0.05) and epidural hematomas were significantly less frequent among helmet wearers (p = 0.03). Ten patients required surgery; helmet use and neurosurgical involvement were not significantly correlated. Conclusions Patients who wore helmets were significantly less likely to suffer from epidural hematomas and open head injuries. While TBI severity was not significantly different between helmeted and non-helmeted bicyclists, the overall occurrence of TBI and moderate to severe TBI among all admissions was lower than that seen in comparable studies from countries without helmet laws.