Thomas left the game in the second quarter with the injury and went to the locker room to receive treatment. He returned to finish the game after receiving a harness and was slated for an MRI on Monday.
Thomas, who was selected to his fourth Pro Bowl this season, said after the game that he was not concerned about missing the Super Bowl, ESPN's John Clayton reports.
"I know who I am, I'm a warrior, bro," Thomas said. "If I can play I don't care if I can't function really well. I know if I can help the team I'm going to be in there."
Seattle, which had the NFL's top scoring defense for the third straight season, limited Green Bay to 306 yards of total offense.
The Seahawks will play the Patriots on Feb. 1 in Glendale, Ariz.
- Paul Palladino