Michael J. Fox is speaking about his “darkest moment.”

The “Back to the Future” actor, who went public with his Parkinson’s Disease diagnosis in 1998, opens up about his struggles in a new interview with People.

Fox explains how, in 2018, a noncancerous tumour on his spine was growing rapidly, causing horrific pain throughout his body.

“I was heading for paralysis if I didn’t get it operated on,” American-Canadian star Fox, who is set to turn 60 in June, shares.

However, he adds the tumour “was constricting the [spinal] cord, so they had to be very careful in removing it so they wouldn’t do further damage.”

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Fox then began a four-month process where he had to learn to walk again after undergoing a successful operation. It was then that he fell in the kitchen and badly broke his arm after returning to New York alone from a family vacation so he could film a cameo in a Spike Lee movie.

The accident happened the morning of the shoot, with Fox saying: “That was definitely my darkest moment.”

The star speaks further about the incident in his upcoming fourth memoir, No Time Like the Future.

“I just snapped. I was leaning against the wall in my kitchen, waiting for the ambulance to come, and I felt like, ‘This is as low as it gets for me.’ It was when I questioned everything. Like, ‘I can’t put a shiny face on this. There’s no bright side to this, no upside. This is just all regret and pain.'”

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“Parkinson’s, my back, my arm… it still didn’t add up to moving the needle on the misery index compared to what some people go through,” he continues. “I thought, How can I tell these people, ‘Chin up. Look at the bright side. Things are going to be great?

Fox now enjoys living a quieter life with Tracy Pollan, his wife since 1988.

The couple share son Sam, 31, twins Aquinnah and Schuyler, both 25, and daughter Esmé, 19.

“It’s not that I wasn’t sincere before, but my gratitude is deeper now, from having gotten through the darkest times,” he says.

Fox then talks more about Parkinson’s, admitting his “short-term memory is shot” 22 years after his diagnosis.

“I always had a real proficiency for lines and memorization. And I had some extreme situation where the last couple of jobs I did were actually really word-heavy parts. I struggled during both of them.”

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