In December last year, Wayne Chivell stopped at a red light on Anzac Highway at Plympton in Adelaide and got out of the car to speak to the driver of the car in front.
He told the other man the back doors of his truck were open.
But when Chivell got back into his car he accidentally hit the accelerator and pinned the truck driver against the back of his vehicle.
The 66-year-old delivery driver suffered such catastrophic injuries that both his legs had to be amputated below the knee.
The magistrate accepted Chivell was remorseful and disqualified him from driving for nine months. He was also fined $900.
Outside court the former state coroner said he hopes to apologise to the victim in person one day.
“I’m very, very conscious of the pain and suffering that I have caused to him and his family,” Chivell said.
“It’s something I very deeply regret.”