Luongo, a two-time NHL All-Star, was injured while making what appeared to be a routine save on a shot by Philippe Boucher about five minutes into the game. He slowly collapsed to the ice and was assisted off while favoring his left leg.
He underwent a second MRI on Monday, which revealed a strained groin. The Canucks said his status was week-to-week.
Curtis Sanford replaced Luongo in goal, stopping 17 of 18 shots to earn the 3-1 win.
Luongo, twice a finalist for the Vezina Trophy, entered the game ranked seventh in the NHL in save percentage (.928) and ninth in goals-against average (2.18) this season for a Vancouver team that has not lost in regulation in eight games.
Information from The Associated Press and ESPN.com's Pierre LeBrun contributed to this report.