Michael J. Fox Reveals Painful Setback That Led to His 'Darkest Moment' Since Parkinson's Diagnosis

Michael J. Fox is opening up about the “darkest moment" of his life that occurred two years ago.

Speaking with PEOPLE for this week's cover story, the Family Ties actor, who went public with his Parkinson’s diagnosis in 1998, discusses the unrelated health setback that led him to question his signature optimism — and how he gained it back.

In 2018, a noncancerous tumor on Fox’s spine was growing rapidly and causing horrible pain throughout his body. “I was heading for paralysis if I didn’t get it operated on,” Fox, 59, tells PEOPLE.

However, the surgery to remove it was risky. The tumor “was constricting the [spinal] cord, so they had to be very careful in removing it so they wouldn’t do further damage,” he says.

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The operation was successful and Fox began a four-month process in which he had to learn to walk again. Thinking the worst was behind him, he vacationed with his family on Martha’s Vineyard and returned to their New York City apartment alone so he could film a cameo in a Spike Lee movie the next day.

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But on the morning of the shoot, Fox fell in the kitchen and badly broke his arm. “That was definitely my darkest moment,” says Fox, who details the story 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.' "

Fox was suddenly, frighteningly unable to tap into the optimism that had long buoyed him. He even feared he had never been qualified to offer hope to others in the first place.

“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”?’ ”

For Fox, watching TV reruns — especially game shows from the 1970s — while being confined to bed for long stretches during recovery helped change his outlook.

From there, Fox says, he found the key to reclaiming his positive perspective.

"Optimism is really rooted in gratitude," he says. "Optimism is sustainable when you keep coming back to gratitude, and what follows from that is acceptance. Accepting that this thing has happened, and you accept it for what it is. It doesn't mean that you can't endeavor to change. It doesn't mean you have to accept it as a punishment or a penance, but just put it in its proper place. Then see how much the rest of your life you have to thrive in, and then you can move on."

The actor, who will turn 60 next June, now says he has a “60-year-old man’s optimism” and is focusing on time with his kids and his wife, Tracy Pollan. The couple shares 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.

And as he continues to live with Parkinson's, he emphasizes that he's thriving in countless ways.

“My life now is quiet, and I’m actually having a really good time,” Fox says. “People don’t believe me, but I love life. I love being with my family. I love being with Tracy. I love that I don’t do a lot of useless stuff that I used to do, because I don’t have the energy or the time. I’m grateful that I went through a crucible there in my late 50s. I figured some of this crap out finally, and it didn’t haunt me into my 70s and 80s.”