It wasn’t Parkinson’s that delivered Michael J. Fox his “darkest moment” – it was a broken bone.

The much-loved actor has opened up about the health scare that made him – momentarily – lose his envied sense of optimism.

Two years ago, at the age of 57, Fox had just recovered from extremely risky surgery to remove a non-cancerous tumour that was growing next to his spine.

“I was heading for paralysis if I didn’t get it operated on,” Fox told PEOPLE this week.

The operation was a success, but Fox faced a rocky four-month recovery to relearn how to walk.

As he writes in his upcoming memoir, Fox had just returned from a holiday with his family, at the end of the four-month period. He was in his New York apartment, preparing to film a cameo.

The morning he was due to shoot, he fell in his kitchen, severely breaking his arm.

“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’,” Fox said.

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“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’.

“That was definitely my darkest moment.”

A beacon of light

Fox was 29 when he was diagnosed with Parkinson’s disease in 1991. He first spoke about it publicly in 1998.

It would take seven years of learning about the disease before he felt comfortable announcing it to the world, which he did not long after undergoing brain surgery.

Fox in 2018, with his broken arm. He said watching reruns of old ’70s TV game shows were a big part of his recovery. Photo: Getty

Since then, he has been a guiding light for the disease and all the people it touches.

His foundation has raised more than $US900 million for research into a cure for the disease, including underpinning a pill-based therapy being trialled at the University of Queensland.

He hasn’t let the disease bring him down, sharing in his book the strength behind his optimism is gratitude.

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“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,” he said.

Fox’s latest book comes out this month. Photo: Flatiron Books

“It doesn’t mean that you can’t endeavour 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.”

That’s why Fox found it so strange for that trademark optimism to disappear in those moments in his kitchen, when, after overcoming so much, he was again facing a setback.

“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 said.

“I thought, ‘How can I tell these people, Chin up. Look at the bright side. Things are going to be great?’ ”

Fox said writing his book, which he did during the pandemic lockdown, was a practice in self reflection.

He said he had to at times ask himself if it was a good thing he was doing, or a selfish thing?

Two years on from that dark moment, Fox insists he is loving life. At the centre of it is his family: wife Tracy and their four adult children.

“My life now is quiet, and I’m actually having a really good time,” Fox told People, the magazine with which he revealed his diagnosis 22 years ago.

“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.”

No Time Like The Future, Fox’s memoir, is released on November 17.