The 23-year-old forward, New York's third-round pick (No. 75) in the 2013 NHL Draft, has nine points (five goals, four assists) in 14 games this season, including six points (three goals, three assists) in his past six games.
"Obviously the last few games, he's been productive offensively and doing all the things he needs to do to be the player he's capable of being." coach David Quinn said. "It's unfortunate that he'll be out an extended period of time. It's life in our sport. We just got to move on, and hopefully he gets better quickly."
Buchnevich has 72 points (27 goals, 45 assists) in 129 NHL games, all with the Rangers.
The Rangers (8-7-2) host the Vancouver Canucks on Monday (7 p.m. ET; MSG, SNP, NHL.TV).
"It's tough. It's hard, not just for himself," forward Mika Zibanejad said. "He started playing more, he was playing better with more confidence and you hate to see that happen to any guy. It's a part of [the game] unfortunately, and we are just hoping for a speedy recovery. Obviously I am going to miss him, but other guys get to step up now and get more ice time."
