A study completed by researchers from the University of California San Diego found that electric bicycle injuries have increased exponentially in the state in the past few years. The study comes as both Los Altos and Santa Clara County ramp up their e-bike safety and education programs.
The study, released July 17, found that the number of injuries involving e-bikes has increased from two in 2018 to 1,506 in 2024. The research paper also revealed that e-bike riders had a higher risk of moderate to severe injuries, as compared to traditional bicyclists, and emphasized that a disproportionate amount of injuries happen with juvenile riders.
“The propensity or the likelihood for risk increases with, in general, folks being younger, in general, folks being male, certainly in patients who are unhelmeted, all of those can increase the likelihood of injury,” said Dr. Joe Forrester, trauma medical director and associate professor of surgery at Stanford University.
The crashes can result in a variety of injuries, some able to cause lasting damage to the body.
“The pattern is usually pretty consistent,” said Dr. Mohanad Alazzeh, assistant medical director and emergency medicine physician at El Camino Health in Mountain View. “You see a lot of facial trauma, a lot of head trauma, broken collarbones, wrists and forearms. You see lots of road rash and dental injuries as well.”
Both Alazzeh and Forrester added that it was not uncommon for them to see e-bike related injuries in the hospital, with Alazzeh saying he comes across an incident at least every other shift.
To combat this, the Los Altos City Council passed an ordinance in June 2025 that prohibits bicyclists from riding on the sidewalk unless a hazard in the roadway prevents them from riding in the street, according to Steven DeBiasio, Los Altos Police Department traffic officer.
“We were getting a lot of complaints, especially in the downtown area, of cyclists flying down the sidewalk and causing hazards that way,” DeBiasio said.
The ordinance also requires riders age 17 and under to wear a helmet and mandates one rider per bike. The law is in addition to the California Vehicle Code, which classifies bikes as vehicles that must follow all rules of the road.
Violators of the ordinance will pay $50 for their first offense, $75 for their second and $100 for the third. But LAPD’s focus is more so on bike safety education, DeBiasio said.
“I think the biggest thing is just educating everybody on the rules of the road associated with bicycles because a lot of our juvenile cyclists haven’t gone through any types of driver’s education,” DeBiasio said. “Our fining somebody for not wearing a helmet is not going to do as much, in our opinion, as educating them.”
In an effort to further educate young riders on bike safety, the Santa Clara County Sheriff’s Office and Stanford Health partnered to reinstate the Juvenile Traffic Diversion Program. Riders can be stopped for riding without a helmet, using unclassified bicycles or not obeying the rules of the road. Riders will be issued a citation, but have the opportunity to attend a two-hour safety course with their parents, in lieu of paying the fines.
“Part of the integral function of a trauma center in the community is working toward injury prevention,” Forrester said. “We want to support the population and the government in trying to identify opportunities to reduce injury before it gets to the point where a patient has to get to the hospital.”
Forrester also emphasized the danger that some e-bikes can cause, and encouraged parents to think before purchasing one for their child.
“My thought process is that it’s basically a small motorcycle, so would you trust your 13-year-old with a motorcycle?” Forrester said. “That’s going to be dependent upon the child … and the child’s ability to understand risk.”
Doctors and public safety officials alike recommend always wearing a helmet, following the rules of the road and maintaining a safe speed to prevent serious injury.
“My recommendation would always be for them to have a helmet on and to always follow all traffic laws,” Alazzeh said. “That’s … the difference between some of these injuries causing you to have a bad day versus a life-changing day.”
