Houston general manager Ed Wade said Berkman's expected recovery time remains two to four weeks, which puts his availability for Opening Day in jeopardy. Wade said team medical director Dr. David Lintner called him early Saturday and told him Berkman had no meniscus or ligament damage.
The surgery was performed by Dr. David Crumbie at Florida Hospital in Kissimmee.
"Our assumption is he'll move in a straight line and we're looking at the two-to-four week recovery time," Wade said. "It would be great if he ended up on the short end of that."
The Astros open the season April 5 against the Giants at Minute Maid Park, giving Berkman a little more than three weeks to get ready for Opening Day. Berkman underwent surgery following the 2004 season on his right knee to repair a torn anterior cruciate ligament and missed the first month of the 2005 season.
Houston manager Brad Mills is hopeful Berkman will be ready on Opening Day.
"The level of concern has gone way down because of [the results of the surgery]," he said. "The doctor says he's fine, so we'll just go off of him and focus on getting him ready and strong."
Berkman missed the first Grapefruit League game of the season with a knee contusion, but he played in the next five games and hit .364. He had the knee drained twice in the last week to remove fluid, but it remained swollen for several days.
Berkman, 34, hit .274 with 25 homers and 80 RBIs last year and had an on-base percentage of .399 that ranked eighth in the National League. He's in the final year of a six-year, $85-million contract with a $15 million option for 2011.
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.