Simon Cowell is expected to be in hospital for "some time" as he recovers from a six hour operation to mend his broken back.
The music mogul had a fall from a new electric bike he was testing at his house in Malibu.
He fell badly onto his back and was taken to hospital where they identified several breaks and rushed him into surgery.
A spokesman for Simon said: “ Simon has broken his back in a number of places in a fall from his bike whilst testing a new electric bike in the courtyard of his home in Malibu with his family.
“He was taken to hospital where they operated overnight, he’s under observation and is doing fine.”
It is understood the surgery started on Saturday evening Los Angeles time – reports Mirror Online.
A source said: "The operation was a success but Simon will be in hospital for a some time yet to recover."
Receive newsletters with the latest news, sport and what's on updates from the Liverpool ECHO by signing up here.
The X Factor boss, 60, lives with his six-year-old son Eric with his partner Lauren Silverman.
Just last month it emerged he has bought Sony Music Entertainment's stake in TV programmes including Britain's Got Talent and The X Factor.
The move sees Simon gain ownership of all the international versions of The X Factor and Got Talent programmes.
The Got Talent format airs in 76 markets, while The X Factor is broadcast in more than 130 territories.
Sony Music's share of the venture has transferred to Syco Entertainment, a company solely owned by Simon.
Keep up to date with local news in your area by adding your postcode below
Filming on the next stage of this year's Britain's Got Talent has been postponed because of the coronavirus crisis but ITV has said it hopes to continue the series later this year.
Simon had started cycling in a bid to improve his fitness following a previous fall at his home three years ago.
The star vowed to take up exercise and embark on a healthier lifestyle after he suffered a frightening fall in 2017.
He had to be stretchered out of his London mansion by paramedics who came to his aid when he fell down his stairs on the way to the kitchen in the early hours of the morning.
Simon said the terrifying incident was a 'wake up call' that made him change his ways.