Celine Dion says 'stiff-person syndrome' is halting her tour — what is it, and what are its symptoms?

“Recently, I’ve been diagnosed with a very rare neurological disorder called the stiff-person syndrome, which affects something like one in a million people,” Dion says in the post. “While we’re still learning about this rare condition, we now know this is what’s been causing all of the spasms that I’ve been having,” she continued. “Unfortunately, these spasms affect every aspect of my daily life, sometimes causing difficulties... + full article