Kaley Cuoco reveals she almost had her leg amputated after horseback riding accident

The course of Kaley Cuoco's life and career — and that of her hit show The Big Bang Theory — was almost changed forever after a harrowing horseback riding accident.

In a new oral history book The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series, Cuoco, co-star Johnny Galecki and series creator Chuck Lorre opened up about the incident, which occurred in Sept. 2010.

Per an excerpt obtained by PEOPLE, Cuoco, who is a longtime horse jumper and competitor, was riding a horse in Los Angeles when it got spooked and she fell off. The horse then tried to jump her, but instead, it landed on her left leg, forcing Cuoco to rush to the hospital for treatment.

In the excerpt, Lorre called the moment "the darkest, most frightening time" in the show's 12-year run. "Kaley could have lost her leg. It was a series of miracles that allowed us to get through that and for her to come out the other end of that healthy," he said.

One such miracle, was that Lorre knew Dr. Stephen Lombardo, who worked for Kerlan Jobe Orthopedic Clinic for Sports Medicine at Cedars-Sinai, and he was able to ask for Lombardo's help. Lorre said his star then was able to, very quickly, be "in surgery with the best surgeons available to stop an infection because her leg was wide open."

Cuoco recalled having to sign an acknowledgement that she could wake up without her leg post-op. "Before I went into surgery, they made me sign something that said, 'We don't know until we get in there and see this leg, and it could come out that you don't have it anymore.' That wasn't the case, obviously, but I had to sign something that said, 'OK, you can,'" Cuoco said. "Everything ended up fine, and I was up and working a week later, but the doctors acted like I was never going to walk again. It's still too much for me to go into, and it sounded way worse than it was. And of course it was spiraling and everyone was freaking out, which I get. It scared people."

"But I think it scared people in a good way, myself included," Galecki added. "The first day I saw you in that state, I just shed tears in my garage."

Per the excerpt, though doctors were concerned that Cuoco wouldn't be able to walk at all for months, she was released from the hospital after two weeks with a walking boot, and ultimately was only written out of the show for two episodes. "It was an absolutely miraculous intervention that I ran into Dr. Steve," Lorre said. "Every time I see him, I say, 'Thank you! You saved Kaley! On a lesser level, you saved The Big Bang Theory!'"

Thankfully, Cuoco otherwise finished out her run on the show as planned, with The Big Bang Theory taking its final bow on May 16, 2019, after 279 episodes spanning 12 seasons.

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