The Turkish midfielder initially sustained the injury in March but he was able to recover in time to participate in EURO 2008.

After impressing with his nation in the elite tournament, Altintop aggravated the earlier injury. He has been sidelined since August.

No specific date has been set for the return of the 25-year-old.

"We’ll talk to the doctors and the coaches, and take each week as it comes," he told Bayern's official website.

"The most important thing is to be completely fit before I return and avoid having to take repeated breaks."

Bundesliga holders Bayern made a disappointing start to the defense of their crown. They are currently 11th in the league table with nine points from seven games.