Two of the nation’s largest e-scooter companies are facing more backlash — this time in the form of mass tort lawsuits filed in California.

The separate complaints against Lime and Bird allege that the companies failed to properly maintain their scooters, resulting in injuries to nearly 90 plaintiffs.

The lawsuits say that malfunctioning brakes, sudden accelerations, and faulty throttles, handlebars and wheels caused riders to be thrown off the two-wheel devices and sustain injuries such as fractures, broken bones, and concussions. Some of the plaintiffs suffered trauma so severe they underwent multiple surgeries and haven’t recovered years later, according to the suits and one of the attorneys.

The lawsuit against Lime was filed this week in San Francisco Superior Court on behalf of 46 people injured while riding the scooters in cities across the country. A complaint filed in May against Bird in Los Angeles Superior Court lists similar incidents and demands compensation for 42 victims.

The lawsuits come as scooter companies are trying to recover from the coronavirus pandemic. Scooter use plummeted starting in early March, bringing unexpected financial pressures on the companies. Lime, which had announced layoffs early in the year, laid off 13 percent of its global workforce in late April. Bird laid off nearly one-third of its 1,400 employees in late March, giving workers the bad news in a two-minute message via Zoom. Both companies have resumed operations in various cities and are citing upticks in ridership.

Catherine Lerer, an attorney with Los Angeles-based McGee Lerer & Associates, one of two firms representing riders in both lawsuits, said the actions seek compensation for the injuries her clients should have never sustained.

“The scooter companies, of course, refuse to take any responsibility,” Lerer said. “The scooters are very poorly maintained. They just fall apart on the riders. The parts come off, the handlebars come off, the baseboard breaks, the throttle sticks, the brakes fail. These are very dangerous motorized vehicles.”

A Lime spokesman said the company is reviewing the lawsuit.

“Lime’s highest priority is the safety of our riders and we take seriously any claims of injuries on our products,” he said. “We have received and are reviewing the claims made in this lawsuit. As the global leader in micromobility, Lime works tirelessly to ensure our riders are fully secure on our scooters and bikes.”

A spokeswoman for Bird said the company doesn’t comment on pending litigation.

Both lawsuits allege that the scooters are unsafe and “contain manufacturing and/or design defects and do not include adequate warnings and use instructions. Defendants are aware that the products will be used without an inspection for these defects and that these defects are not apparent.”

The complaints also say that the scooters “failed to perform as safely as an ordinary consumer would expect when used.”

Most of the incidents listed in both suits date back to 2018 and the early part of 2019, coinciding with the first year of operations for the services in some of the cities. In many of the cases, riders were using the companies’ early-generation scooters, some of which have been replaced with newer models, which Bird and Lime say include improved safety features.

The devices, which became wildly popular soon after entering U.S. markets in late 2017, are in dozens of cities nationwide and have led to a new category of injuries in emergency rooms. An uptick in severe injuries — from broken noses, wrists and shoulders, to facial lacerations and fractures — have been linked to the use of the devices.

The lawsuits are the latest in a string of actions against scooter companies alleging maintenance and safety failures and other concerns. A class-action lawsuit filed in state court in California in fall 2018 against Bird, Lime and other scooter companies alleged gross negligence.

Lerer said her firm has filed or is preparing separate lawsuits against Lyft, Spin and Bird on behalf of pedestrians, most elderly, who were injured after tripping over or being struck by scooters.

Concerns about the safety of the devices have been around since they began operating, and some operators have pulled their fleets from cities due to defects, including battery issues and software glitches.

Earlier this year, the Wall Street Journal Pro reported that because of shortages, mechanics for Bird and Lime were forced to use old parts, including brakes, to make repairs.

Critics — including doctors, former riders and personal injury attorneys — claim that scooter fleets are poorly maintained and prone to dangerous mechanical failures.

“Scooters are marketed as so easy to use — you can pick them up anywhere, drop them off anywhere. There’s no training or instruction provided, other than very few pages in the app,” Lerer said. “Generally the riders who get on them have little to zero experience riding. They have no idea the danger they’re about to encounter.”

Some industry experts say complaints about the services have gone down as people have gotten used to having the devices in their communities, and many have embraced them as critical to their transportation networks. Injuries have also decreased, some say, because riders have learned to use them and newer scooter models offer more protections.

The Lime lawsuit also names scooter manufacturer Segway Inc. as a defendant. The suit against Bird names scooter manufacturers Xiaomi USA Inc. and Segway Inc. as defendants.

The plaintiffs listed in the suits suffered injury in states across the country, including California, Ohio, Arizona and New York, as well as the nation’s capital.

Evan Sutton, a plaintiff in the Lime lawsuit, said he was riding a scooter in downtown Washington on a June 2018 morning when the scooters abruptly stopped, causing him to be thrown off. Sutton fractured his right kneecap, requiring two surgeries, according to the lawsuit.

In an interview, Sutton, a union and political campaign consultant who lived in the D.C. area at the time, said he had been using the scooters frequently to get to meetings in downtown Washington. They were convenient for short haul trips, he said. That morning, he rented a Lime scooter and was just a half block into his trip when he fell, he said.

“I went flying,” said Sutton, 41, who alleges the scooter he was riding was faulty. “I landed on my knee and cracked the patella straight across the middle.”

Sutton underwent surgery, was in a cast for four weeks, then in a brace for two weeks, and underwent physical therapy for a year. Complications from the earlier procedure led to a second surgery.

Sutton said he is still recovering, suffers from pain and hasn’t regained all the motion in his leg. He said he spent hundreds of hours in medical appointments and therapy and thousands of dollars in co-pays, deductibles and home equipment.

“There’s a whole bunch of activities that I can’t do anymore that I used to do,” Sutton said. “This caused a ton of pain, a huge amount of money, and ongoing disruption to my life. It would be great if I could at least get some recompense for the money that I ended up spending, especially considering that it certainly appears that I may have been riding a scooter that the company knew was faulty and left on the street anyway.”

Lime, one of the world’s largest scooter companies, last year urged riders to take precautions while operating its scooters, citing a technical “bug” that at the time could cause “sudden excessive braking during use.” The company also pulled scooters out of California in 2018 after discovering that a number of them may have been carrying batteries with the potential to catch fire.

The companies have said safety is a top priority, and they encourage users to take precautions such as avoiding wearing headphones or carrying anything in their hands while riding. Both have basic safety information on their apps and labels on their scooters, as well as training instructions. Both companies say they have programs to provide free helmets.