What is Lady Gaga condition synovitis?

February 12, 2013 10:00:00 PM PST
Lady Gaga canceled the rest of her "Born This Way Ball" tour dates Thursday because she can't walk.

She blames it on a hip injury that's left her in chronic pain, a condition called synovitis.

What is synovitis?

It's caused when the synovium, a liner and lubrication of the knee joint, becomes inflicted with inflammation or swelling.

This can be caused by injury or other issues.

"The patient sets up an inflammatory response to those damaged components and gets synovitis which is painful," a rheumatologist at Loyola University Medical Center Dr. John Robinson said.

"It can be multiple joints and that can be due to systemic diseases like rheumatoid arthritis. Gout can also cause synovitis," Robinson said.