Lopez will meet with a hand specialist on Tuesday in Portland.
Lopez suffered the injury pursuing a rebound in the Blazers victory over the San Antonio Spurs on Monday night at the Moda Center.
For the Trail Blazers, the loss of Lopez will necessitate more prominent roles for Chris Kaman and Joel Freeland. Lopez has been a pillar for the Blazers in his two seasons, failing to miss a game. His rim protection and physicality in the post has made him an invaluable complement to All-Star forward LaMarcus Aldridge.
For the season, Lopez is averaging 9.6 points and 7.2 rebounds.
The Blazers are 19-6 and holding onto fourth place in the Western Conference.
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