Céline Dion delivers emotional performance at the Paris 2024 opening ceremony — her first since cancelling tour due to Stiff Person Syndrome: Signs, symptoms & how it affected her voice

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Céline Dion made her triumphant return to the stage with an emotional performance at the Paris 2024 Olympic Games opening ceremony. The 56-year-old performed Edith Piaf's "L'Hymne à l'amour” on top of the Eiffel Tower. A teary-eyed Dion's performance was met with cheers from spectators watching from below.

It was the first time Dion has performed publicly since she was forced to cancel the 2023 and 2024 dates of her Courage world tour.

What is Stiff Person Syndrome? Continue reading to learn more about the neurological condition and its symptoms that have plagued Dion for the last 17 years.

What is Stiff Person Syndrome (SPS)?

As per the Stiff Person Syndrome Foundation, the condition affects the central nervous system, specifically the brain and spinal cord. People with SPS "can be disabled, wheelchair-bound or bedridden, unable to work and care for themselves." The syndrome is characterized by muscle spasms and rigidity, severe stiffness and pain.

SPS patients also have a heightened sensitivity to stimuli such as noise, touch and emotional distress, which can set off the spasms.

While SPS is a rare disease, more people are affected than reported due to misdiagnoses. Overall, it can take up to seven years to identify.

SPS can often be mistaken for multiple sclerosis, Parkinson's, fibromyalgia, psychosomatic illness, anxiety, phobia and other autoimmune diseases.

How Stiff Person Syndrome (SPS) affects Celine Dion's singing voice

In an Instagram clip, the singer shared SPS had affected "every aspect of [her] daily life."

"Sometimes causing difficulties when I walk and not allowing me to use my vocal cords to sing the way I'm used to...I have to admit it's been a struggle," she said.

SPS affects the muscles near Dion's vocal cords, which may impact the sounds of her voice.

Dr. Marinos Dalakas, a professor of neurology at Thomas Jefferson University in Philadelphia, told CTV News last year several of his patients with SPS have ongoing muscle stiffness.

"When this affects the diaphragm or affects the laryngeal muscles or the vocal cord muscles, the voice becomes very thin, it doesn't come out strong, it is fragmented," he said.

"The singers might get the stiffness more and then because the voice is so important for them the spasms are focussed more there."

What are the signs and symptoms of Stiff Person Syndrome?

The typical symptoms of SPS include muscle rigidity, hyper-stiffness and "spasms in muscles of the trunk, including the back and limbs." The severity of the tremors is variable from episode to episode.

Moreover, the neurological disease has autoimmune features that can also include "debilitating pain, chronic anxiety" and muscle spasms "so violent they can dislocate joints and even break bones."

In the early stages of SPS, spasms and stiffness may be subtle and fluctuate on a daily basis. There can be periods when symptoms seem stable, while other times, they can be more noticeable and rapid.

At times, the muscle spasms may be brief, lasting minutes. However, they can also last hours or days.

Other key warning signs include changes in posture, increased stress and anxiety, and trouble breathing.

If you or someone you know is experiencing any of the above symptoms, contact your doctor or a medical professional as soon as possible.

Who is at risk of Stiff Person Syndrome?

SPS is extremely rare and affects twice as many women as men. Symptoms can occur at any age but usually develop between ages 30 and 60.

The condition is usually associated with other autoimmune diseases such as vitiligo, diabetes, pernicious anemia and thyroiditis.

As a whole, health professionals are unsure what exactly causes SPS, but some research indicates it's the result of a faulty autoimmune response in the spinal cord and brain.

How is Stiff Person Syndrome treated?

Currently, there is no cure for SPS. Treatment focuses on pain relief and symptom management associated with muscle spasms, such as physiotherapy, a stretching and strengthening program and massage therapy.

In some patients, immunotherapy and other medications may help to reduce stiffness, pain and specific autoimmune abnormalities. That said, most people with SPS have at least some degree of disability.

If depression and anxiety are present, mental health therapy is encouraged, along with visiting a pain and chronic illness centre for regular check-ups.

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