Head Injuries Common in E-Scooter Accidents

Head injuries topped the list of emergency room injuries involving electric scooters, yet very few e-scooter riders wore helmets, an observational study found.

About 40% of patients treated for two-wheeled e-scooter injuries at two southern California emergency departments had head injuries, but only 4.4% wore a protective helmet, reported Tarak Trivedi, MD, MS, of the University of California Los Angeles (UCLA), and colleagues.

And in a convenience sample of traffic observed in Los Angeles, 182 of 193 e-scooter riders were helmet-less, the team wrote in JAMA Network Open.

Shared electric scooters from companies like Bird, Lime, Skip, and Scoot are in over 100 cities now and can reach speeds up to 15 mph. “There are thousands of riders now using these scooters, so it’s more important than ever to understand their impact on public health,” Trivedi said in a statement.

Despite the wild popularity of rental scooters — Bird tallied 10 million rides in its first year — cities have adopted mixed responses to their safety issues. Los Angeles-area emergency departments are at the epicenter of the electric scooter phenomenon, Trivedi said: the shared vehicles first appeared in Santa Monica in September 2017 when Bird placed thousands of them around the city.

In their study, the researchers reviewed medical records of 249 emergency room patients who presented with injuries associated with electric scooters at UCLA Medical Center in Santa Monica and Ronald Reagan UCLA Medical Center in Los Angeles from September 2017 to September 2018. Patients were an average age of about 34, and 58.2% were male. Most patients (91.6%) were injured as e-scooter riders and 8.4% as non-riders.

The cases showed the following:

• About one in 10 patients (10.8%) were younger than 18

• Only 10 patients (4.4%) were documented as having worn a helmet

• Head injuries (40.2%), fractures (31.7%), and contusions, sprains, and lacerations without fracture (27.7%) were most common

• Most head injuries were minor — without intracranial hemorrhage or skull fracture — but five patients (2.0%) had an intracranial hemorrhage

• Fifteen patients (6.0%) were admitted or transferred, including two patients to the intensive care unit — one with traumatic subarachnoid hemorrhage and another with a subdural hematoma

During three public observation sessions on Los Angeles streets, the researchers also found that 94.3% (182 of 193 e-scooter riders) did not wear a helmet.

Traumatic brain injury (TBI) is the most common cause of serious morbidity and mortality in bicycle crashes, noted Frederick Rivara, MD, MPH, of the University of Washington in Seattle, in an accompanying editorial. But the bicycle world has taken steps to prevent harm: cities have built bike lanes to separate riders from motor vehicles, and bicycle helmets can reduce TBI risk by as much as 88%.

But shared two-wheeled devices “turn all of this on its head,” Rivara wrote. “None of the companies that rent these vehicles in the increasingly common hubless system provide helmets,” he noted. And it’s not clear what kind of helmet would be best: “There are no data on whether bicycle helmets would provide adequate protection against serious TBI for these motorized devices, which can attain higher speeds than would be achieved by most bicyclists on flat roads.”

Action is needed on a number of levels, Rivara argued. “The Consumer Product Safety Commission should test different helmets for these various devices and label them according to the vehicle in which their use is appropriate,” he asserted. “Just as helmet manufacturers responded to the increased demand for bicycle helmets with new and attractive products priced very affordably, these manufacturers should develop and promote use of helmets appropriate for electric scooters and bikes.”

Companies renting two-wheeled vehicles should make helmets available — “failure to do so is like a car rental company renting cars without seat belts,” Rivara contended — and cities should require helmets as part of their contracts with the shared-vehicle companies. “We as purveyors of healthcare and public health should partner with these other players to ensure that these companies are not creating a new public health problem,” he wrote.

Trivedi and colleagues noted several limitations to their review: it was limited to clinical variables and other information, like helmet use was not always recorded. The study could not identify risk factors for injury, and outpatient visits to urgent care or primary care clinics for minor injuries were not included.