By Lindsay Lowe | (staff@latinospost.com) | First Posted: Feb 14, 2013 08:55 AM EST

Lady Gaga has cancelled the remaining performances of her Born This Way Ball world tour because she needs hip surgery.

Lady Gaga had initially postponed four upcoming shows in Chicago, Detroit, and Hamilton, Ontario, after suffering from "severe joint inflammation," according to Reuters.

This morning, her touring company Live Nation Global Touring issued a statement saying the entire tour has now been cancelled:

"After additional tests this morning to review the severity of the issue, it has been determined that Lady Gaga has a labral tear of the right hip. She will need surgery to repair the problem, followed by strict down time to recover. This unfortunately will force her to cancel the tour so she can heal."

Live Nation added that refunds for upcoming concerts "will be available at point of purchase" starting today, Feb. 14.

Lady Gaga had not commented about her upcoming surgery as of Thursday morning, but on Wednesday, she said she was devastated about even having to cancel four upcoming shows.

"I am completely devastated and heartsick," she said in a statement provided by Reuters. "I've been hiding this injury and pain from my staff for a month, praying it would heal, but after last night's performance, I could not walk."

The singer said she had been diagnosed with synovitis, an inflammation of the joints that can result from a sprain or strain.

"To the fans in Chicago Detroit & Hamilton I hope you can forgive me, as it is nearly impossible for me to forgive myself. I'm devastated & sad," she tweeted Tuesday to her 34 million followers, adding, "It will hopefully heal as soon as possible, I hate this. I hate this so much. I love you and I'm sorry."

Lady Gaga's Born This Way Ball, the singer's third world tour, would have included 110 dates in every continent except Antarctica, Billboard reports, and promoted Lady Gaga's second studio album, "Born This Way." The singer has already played dozens of shows in Australia, Asia, and Latin America, says Billboard, and the cancelled shows were part of her North American leg, which would have continued into March, according to her website.

Lady Gaga's previous 'Monster Ball' tour grossed $188 million from 167, according to Billboard, and was nearly "the highest-grossing tour ever by an artist making their global run through arenas and stadiums."