The Netherlands international had to be substituted 37 minutes into Hamburg's shock 3-0 home defeat at the hands of Paderborn after sustaining the knock.
However, Van der Vaart does not believe he will miss out on any club action, despite withdrawing from the Dutch squad for fixtures against Italy and Czech Republic.
"I think I can play for Hamburg again in two weeks at Hannover," he is quoted as saying by Bild.
Hamburg are yet to score this season, having been held to a goalless draw at Cologne prior to their loss against Paderborn.
Van der Vaart has scored 12 goals in 56 league appearances for Hamburg since returning to the club from Tottenham in 2012.