The Britain’s Got Talent judge was rushed to hospital after breaking his back during the fall and ended up undergoing six hours of surgery to have a metal rob inserted.
Looking back on his recovery in a new interview, the TV mogul admitted he deliberately withheld the severity of his condition from the public.
“I didn’t talk about it too much at the time,” the 62-year-old told OK! magazine. “I kept a lot back. It was a lot worse than people thought. I had a lot of long-term nerve damage as well.”
He says he caused himself a lot of pain kicking a football with his son Eric, and then later had a setback with a second bike accident in February, but now is on the road to recovery.
“It’s been a long haul but I’m almost healed and I’m being very careful about what I do. But at least now I can actually play football with Eric.”
He added: “If there was one good thing about lockdown, it was that it gave me the time to heal because I wasn’t working on a TV show.
“I was able to walk a lot and strengthen my legs. I know I was lucky to survive my back surgery. I have a lot of people to thank for my recovery.”
In August 2020, Cowell broke his back while testing out his new £10,000 e-bike in the courtyard of his Malibu home.
The injury forced him to miss filming of BGT during which he was temporarily replaced by Diversity star, Ashley Banjo.
A spokesperson for Cowell stated at the time: "Simon is understandably extremely concerned for other peoples' safety in relation to this bike.
"We have been pressing the manufacturers about this and will continue to press them, including in relation to the claims of the former member of staff."
Cowell eventually chose not to follow through with the legal action and later claimed to have downgraded his bike to something a little less professional.
Watch: Simon Cowell sunk into depression after his horror E-bike crash