Brad Lidge had arthroscopic surgery on his right knee Wednesday, and his status for Opening Day is up in the air, the club announced in a news release Thursday. The team's physician, Dr. Michael Ciccotti, performed the surgery at the Rothman Institute at Thomas Jefferson University Hospital. It consisted of "the removal of loose bodies and meniscal debridement," the release stated. "The surgery went well, and Brad is expected to begin his throwing program in 10 days," Phillies head athletic trainer Scott Sheridan said in a statement. "We're not sure if he'll be ready by Opening Day, but we don't expect that he'll be too far behind. This surgery was not directly related to any previous surgeries."