Schwarzenegger, 58, was riding a Harley Davidson with Patrick in the sidecar when another driver backed into the street. "The governor was unable to avoid the vehicle in his path and collided with it at a low speed," said spokeswoman Margita Thompson.
Both Schwarzeneggers were treated for cuts and bruises at St. John's Hospital in Santa Monica and released, Thompson said. Both were wearing helmets at the time of the mishap, and both are recovering at home as of Sunday night, she said.
The elder Schwarzenegger was due back on the job Monday, and the driver of the vehicle was neither injured nor cited, said police spokesman Officer Jason Lee.
In December 2001, Schwarzenegger broke six ribs and was hospitalized for four days after a motorcycle crash in Los Angeles. "It was very painful, much more painful than the heart surgery," he said at the time, referring to an operation he had in 1997 to replace a heart valve. "A rib breaking is, like, the worst."