'Heartbroken' star's haunting reveal after shocking Olympics incident

American skier Nina O’Brien has opened up in painful detail about the terrifying incident at the Winter Olympics that shocked onlookers and left her with multiple leg fractures.

O’Brien crashed across the finish line in her second Olympic giant slalom run, sending gasps throughout an audience that included many fellow racers.

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Doctors and emergency responders tended to her on the icy snow for almost 10 minutes, before dragging her away from the finish area on a stretcher.

Team officials from the USA revealed afterwards that O’Brien was "alert and responsive" in a positive update about the 24-year-old's condition.

The Californian has since undergone surgery in China after suffering compound fractures of her left tibia and fibula from the high-speed crash.

O'Brien - who was replaced by teammate AJ Hurt for Wednesday’s slalom race - is set to fly home to the United States for further treatment.

In a devastating admission on social media, the American says she's been left haunted by the moment that shattered her Olympics dream and left her "heartbroken".

“I keep replaying it in my head, wishing I’d skied those last few gates differently. But here we are," O'Brien posted on Instagram alongside a series of photos of her in hospital.

“I had surgery last night to stabilise my tibia, which unfortunately was an open fracture through my leg.

“I’ll get the rest fixed at home, but for now I’m in great hands.

“I want to say thank you to everyone who’s taken care of me, especially those who rushed to me in the finish and my doctors and nurses in Yanqing.

“I’m a little heartbroken but also feeling so much love. My phone is flooded with messages. Waking up to those words means more than you can know.”

Nina O'Brien crash left onlookers shocked

O’Brien was one of dozens of skiers who wiped out of the first Alpine race at these Games, the women’s giant slalom. She entered the second of two runs in sixth place, after a morning run that was “really fun.”

She said the hill was “in perfect shape" and “had no idea” at the time that others, including teammate Mikaela Shiffrin, had failed to finish.

She lost balance after clipping one of the final two gates. Her skis split, her right knee appeared to bend underneath her at an awkward angle, and she tumbled toward and over the finish line as her skis and poles went flying.

Several metres away, multiple skiers brought their hands to their mouths in horror.

Shiffrin, who slipped during her first run, bowed her head and covered her eyes, before posting an emotional message to her compatriot on social media.

"It's just sooo not even close to fair," Shiffrin wrote.

"The warrior that she is, she will get back stronger and speedier than ever, with the same upbeat and kind attitude that is trademark Nina. But tonight we're all just sad and crossing our fingers for the best news possible."

"We are so heartbroken for Nina... she showed so much heart and fire in her skiing today, and it all got shredded to pieces on the final turn. This sport... this sport is SO damn hard. It’s brutal, and it hurts - far more often than it ever feels good."

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