The Senators 2022 All-Star was hurt during the first period during Ottawa's 5-0 win over Buffalo after he was hit by Sabres goaltender Aaron Dell and fell awkwardly into the end boards.
"We're looking at a couple of months, if not more," Senators head coach D.J. Smith said.
Batherson was the Sens' leading scorer with 34 points (13 goals) in 31 games and earlier this month had been named to the his first NHL All-Star game. He was subsequently replaced by Brady Tkachuk Wednesday.
"We all know Bath deserved to be there," Tkachuk said. "He's had such a great year for us and is such a big part of our team. We're going to miss him a lot."
Additionally, Dylan Gambrell, who also left Tuesday's contest in the first period, is expected to miss the next couple of games, according to Smith.
Connor Brown, who broke his jaw Jan. 13, and Nikita Zaitsev, who has been out since Dec. 16 with a heel injury, are expected back after the All-Star break although Smith suggested there is an outside chance they play one game before the break.
