But other cities with electric scooters have seen hundreds of injuries, from broken arms to brain trauma, mostly affecting riders, though bystanders also have been hurt. There were at least five reported U.S. shared e-scooter deaths just in the past nine months. That’s compared with four U.S. bike share deaths since the mode was first introduced in 2007, according to Paul DeMaio, principal of MetroBike, a bike-share consulting business.