S Club 7's lead singer Jo O'Meara has checked into hospital for emergency back surgery after being left in "horrendous pain" from an old injury.
The 43-year-old singer, who injured her back in 2002, was admitted on Thursday to remove a disc.
She had taken to Twitter and Instagram on Wednesday to tell fans and apologise for having to pull out of a scheduled performance.
"I am so sorry to announce, that I will not be able to attend @PrideFife on Saturday," she wrote alongside a photo of herself in her hospital gown.
"I have had some health issues with my back and it has resulted in me needing surgery to remove a disc.
"I will be going in to hospital tomorrow I am truly sorry to you all."
Fans were quick to share their well-wishes in the comments.
One wrote: "I really hope all goes well X take care you fabulous beautiful lady", while another added: "Hope surgery goes well Jo. Heal up soon."
O'Meara had first visited hospital seven days ago after her back gave in during rehearsals with her band. She told her followers alongside a snap of herself in a hospital bed.
"So after almost 20 years pain free my back decided it was time to flake out on me again.
"The pain has been absolutely horrendous! 4 discs bulging, and a bad case of sciatica, I yesterday went for spinal blockers at the amazing @thelondonclinichospital to try and get things moving again.
"It will not stop me doing my shows, and I will not be beaten by it... I look forward to seeing you all at Gloucester Pride this weekend where I will be headlining and the following week I will be Headlining at Fife pride!"
The Never Had a Dream Come True singer first injured her back in 2002 while filming S Club 7's movie Seeing Double.