Lightning head coach Jon Cooper said after his team's 4-2 victory that Hedman "is probably done" for the rest of Tampa Bay's current road trip, which still has four games remaining.
The 23-year-old appeared to be favouring his right hand before leaving about halfway through Saturday's contest.
"It's unreal how these things happen but he is going to go back to Tampa and get re-evaluated, said Cooper. "We're hoping for the best, I'm just going to leave it at that."
Hedman has three goals and four assists in five games so far this season for the Lightning.
"We're going to test our depth," said Cooper, whose team improved to 3-1-1. "It just puts a little more pressure on the (defensive) core."