Yao was injured in the first quarter of Houston's 98-91 loss to the Washington Wizards on Wednesday night. An MRI taken Thursday in Indianapolis confirmed the injury. Yao will return to Houston to begin rehabilitation while the team finishes its road trip.
The Rockets have been closely monitoring Yao's minutes this season in his return after sitting out all of last season following surgery to repair his broken left foot.
Yao, a seven-time All-Star, is averaging 10.2 points and 5.8 rebounds while averaging 18.2 minutes a game for the struggling Rockets, who are 1-6.