Celine Dion has again halted all performing after being diagnosed with a rare neurological condition she fears might turn her into “a human statue”.

In tearful video messages in French and English posted to Instagram on Thursday, 54-year-old Dion said the rare stiff person syndrome was causing spasms that affected her ability to walk and sing.

“Recently I’ve been diagnosed with a very rare neurological disorder called the stiff person syndrome, which affects one in a million people,” she told her 5.2 million Instagram followers.

“While we’re still learning about this rare condition, we now know this is what’s been causing all the spasms I’ve been having.

“Unfortunately, these spasms affect every aspect of my daily life sometimes causing difficulties when I walk and not allowing me to use my vocal chords to sing the way I’m used to.”

Stiff person syndrome is a disorder of the central nervous system characterised by progressive fluctuating rigidity and painful spasms of the body musculature, according to the University of Queensland.

The condition can leave sufferers as “human statues” as it progressively locks the body into rigid positions. There is no known cure, and treatment focuses on offering relief to sufferers.

An emotional Dion said she had no choice but to postpone her Courage tour, which had been due to restart in February after several delays.

“All I know is singing. It’s what I’ve done all my life and it’s what I love to do the most,” she said.

The first sign there might be something wrong with the singer came when Dion announced unexpectedly in October 2021 that she had to cancel shows for her Las Vegas residency, which had run for 19 years.

Earlier this year, she also rescheduled dates for her world tour to promote her 2019 studio album Courage, after developing “severe and persistent muscle spasms”.

The tour had already been hit by the COVID pandemic, forcing the cancellation of many earlier dates.

“I miss seeing all of you, being on the stage, performing for you. I always give 100 per cent when I do my shows but my condition is not allowing me to give you that right now,” Dion told her fans on Thursday.

After Thursday’s announcement, her shows for the 2023 northern hemisphere spring have been moved to 2024 and her summer 2023 concerts have been cancelled.

In 2014, Dion, who won an Oscar for the Titanic theme song My Heart Will Go On and has won five Grammys, put her career on hold “indefinitely” as her husband René Angélil battled cancer.

She resumed performing about a year later, only to again step away from the stage in early 2016, following the deaths of Angélil and her brother, Daniel Dion.

Dion eventually returned with Courage, which featured collaborations with Sia, Sam Smith and David Guetta.

On Thursday, she said she had “a great team of doctors working alongside me to help me get better” while her “precious children” – twins Nelson and Eddy, and René-Charles – were “supporting me and giving me help”.