Despite claims that helmets do not protect the cervical spine during a motorcycle crash and may even increase the risk of injury, researchers from the University of Wisconsin Hospitals and Clinics in Madison found that, during an accident, helmet use lowers the likelihood of cervical spine injury, particularly fractures of the cervical vertebrae. These findings were originally published in the Journal of Neurosurgery: Spine.
The study investigators conducted a retrospective patient chart review for all motorcycle crash victims (1064 patients) evaluated at a level one academic tertiary referral center between 1 January 2010 and 1 January 2015, by examining the TraumaBase database maintained by Clinical Data Management. Patients were divided into two distinct groups—323 helmeted (30.4%) and 738 unhelmeted (69.6%)—, with neurological function outcomes and mortality compared between the two groups.
At least one cervical spine injury was sustained by 7.4% of the riders wearing a helmet and 15.4% of those not wearing one; this difference in percentages is statistically significant (p=0.001). Cervical spine fractures occurred more often in patients who were not wearing helmets (10.8% compared to 4.6%; p=0.001), as did ligament injuries (1.9% compared with 0.3%; p=0.04); again these differences are statistically significant. There were no significant differences between groups (helmeted vs. unhelmeted riders) with respect to other types of cervical spine injuries that were sustained: nerve root injury, cervical strain, or cord contusion.
Throughout the European Union, universal legislation requiring motorcycle helmet use is applied. In the USA, however, laws on helmet use vary from state to state, with some states requiring helmet use for all riders, others limiting the requirement to specific demographics, and some states having no mandatory use. Like 21 other states, Wisconsin currently has a partial helmet law, which requires only individuals under the age of 18 years and persons with instructional permits to wear helmets.
Compared with automobile drivers, motorcyclists are 30 times more likely to die in a traffic-related accident. In 2015 alone, 88,000 motorcyclists were injured and 4594 were killed according to the National Highway Traffic Safety Administration (NHTSA). According to NHTSA estimates, wearing helmets saved the lives of 1859 motorcycle riders in 2016; an additional 802 lives could have been saved if every motorcyclist had worn them.
Wearing a helmet decreases the incidence and severity of traumatic brain injury during crashes.
However, implementation of laws specifying mandatory motorcycle helmet use have been controversial in the USA. Major objections cited for not requiring helmets while riding a motorcycle include individual freedom of choice, avoiding any limitation on vision, and a perceived risk of receiving a cervical spine injury. This last reason is based on the belief that the added weight of a helmet might increase torque on the cervical spine.
Risk to the cervical spine is addressed in this study; first author Paul Page (Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, USA) and colleagues hypothesise that helmet use is not associated with an increased risk of cervical spine injury during a motorcycle crash, and instead may provide some protection to the wearer. Their data show that helmet use is associated with a significantly reduced likelihood of sustaining a cervical spine injury during a motorcycle crash, particularly fractures of the cervical vertebrae.
Although the study population is small, the authors believe the results provide additional evidence in support of wearing helmets to prevent severe injury in motorcycle crashes. Nathaniel Brooks (Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, USA), one of the study authors, summarises, “Our study suggests that wearing a motorcycle helmet is a reasonable way to limit the risk of injury to the cervical spine in a motorcycle crash.”