Lady Gaga underwent surgery on Wednesday to repair a torn labrum in her hip.

"Going in for surgery now," the "Poker Face" singer tweeted. "Thank you so much for sending me love and support. I will be dreaming of you."

The singer, 26, announced Feb. 12 that she is suffering from synovitis, an inflammation of the joints that can cause significant pain, significant swelling and reduced range of motion. Subsequent tests revealed that she had a labral tear in her right hip.

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"The hip joint is an incredibly complex joint," said Dr. Jennifer Ashton, a senior medical contributor for ABC News, who is not treating Gaga. "There's a lot involved in this surgery and there's a lot involved in the recovery."

The labrum is a layer of muscle that helps holds the ball-shaped hip joint in place. Gaga's team previously said the surgery will require strict downtime.

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"The rehabilitation or recovery after this type of surgery is generally around four months," Ashton said. "After that period of time, the expectation is no limitations."

The injury had already forced Gaga to announce last week that she was canceling the remaining dates on her "Born This Way" tour. The pop star had previously canceled four dates on the tour, explaining in a tweet to fans that she'd been hiding a show injury that had gotten worse.

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"I hid it from my staff, I didn't want to disappoint my amazing fans. However after last night's performance I could not walk and still can't," she tweeted Feb. 12.

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The fans who Gaga calls "Little Monsters" responded with an outpouring of support and well wishes on social media.

"I love you and am proud to be a part of your lives," Gaga replied online Wednesday. "If you can do it, I can do it too, and if we stick together we can get through anything."

Raha Lewis of People magazine said, "As much as they love her, she loves them right back."

There were 21 shows left on her tour. People holding tickets for the canceled shows will receive refunds.

The Associated Press contributed to this report.