Shocking footage has emerged from the US of a car appearing to pull in front of a motorcyclist leading to a nasty-looking accident.

The video, filmed on the motorcyclist's helmet cam near San Francisco in August, shows the terrifying moment he was thrown from his bike after hitting the side of the car.

"I was riding my motorcycle day before I was to start college and the car didn't yield to me and hit me," he alleged online.

"I went to the ER where I had bruised lungs, concussion, minor neck sprain, and a broken femur."

"I now lost my chance to play college football, missed out the first year of college and have two screws in my leg," he continued.

I was riding my motorcycle day before I was to start college and the car didn't yield to me and hit me. I went to the ER where I had bruised lungs, concussion, minor neck sprain, and a broken femur. I now lost my chance to play college football, missed out the first year of college and have two screws in my leg.