Usain Bolt's celebrations after completing a world championship sprint double came to a painful halt on Thursday after he was knocked over by a cameraman on an electric scooter.

The bizarre accident happened when the cameraman strayed too close to a barefoot Bolt as he posed for photos following his gold medal run in the 200 metres in Beijing.

The local television journalist bumped into a fixed railing and went flying off backwards, shooting the scooter into Bolt's legs from behind and sending the Jamaican crashing to the ground.

Bolt climbed gingerly to his feet to complete his lap of honour.

"He took me out," said the Jamaican after videos of his mishap quickly went viral. "The rumour I'm trying to start right now is that Justin Gatlin paid him off, so that's what I'm going with. But I'm all right so it's all good."

Bolt's American rival quickly shot back: "I want my money back, he didn't complete the job!"

Lucky to escape with only his pride hurt, Bolt pondered getting his legs insured in case of future bumps and scrapes after winning his fourth consecutive world title in the 200m.

"I probably should get my legs insured," smiled the six-times Olympic champion. "It was pretty scary when it happened but accidents happen.

"I have a few cuts but it's nothing that I've never done to myself in training so I'll be all right," added Bolt. "He didn't hit me in my ankles, he hit my in my calf area so I'll get over it."

Bolt, winner of an astonishing 11 of the last 12 individual world and Olympic sprint titles since he shot to fame at the 2008 Beijing Games, revealed that the red-faced cameraman had apologised for mowing down the biggest name in athletics.

"He said sorry as much as he could," said Bolt with a chuckle. "But I checked to make sure if he was okay because I think he got the worst of it. He was off-balance going backwards and I'm not sure if he hit his head but I'm just happy that he's okay. I'm fine so it's all fun."

In the chaos that followed the final, Bolt also lost his spikes to a spectator who ran away with them.

"When I jumped over the fence I gave a guy who was calling me my spikes to hold," he said. "When I did my interview I looked around and he was gone, he was just running."