However, Bush is expected to be ready for minicamp in June.
Saints GM Mickey Loomis said Bush had a microfracture procedure performed on his left knee after he was placed on injured reserve in mid-December, according to the New Orleans Times-Picayune.
Sean Payton had indicated last week that Bush underwent an arthroscopic procedure performed by Dr. James Andrews in Birmingham, Ala.
Loomis said the surgery was not a "major" procedure, according to the report.
"I wouldn't want to call it minor, because he's got a pretty significant period of rehab time," Loomis told the Times-Picayune. "But at the end of it, he shouldn't have any issues."
The surgery entailed drilling small holes in the bone around the knee joint in order to generate soft tissue that mimics the padding effect of cartilage.
Bush has had repeated problems with his left knee the past two seasons. He was placed on injured reserve after the latest injury in the Dec. 11 game against Chicago.
Bush's injury initially was reported as a sprained medial collateral ligament, which doesn't usually require surgery. But the team confirmed Wednesday that he had surgery.
Information from The Associated Press was used in this report.