Boychuk was down on the ice for several minutes, bent over, before he was placed onto a stretcher and had his head immobilized as he left the ice.
The injury was suffered as Pacioretty hit him into the boards as Boychuk was turning. Boychuk’s left side went into the boards first and he appeared to be jammed as the rest of his body hit the boards. Pacioretty, who appeared to be going for Boychuk’s on the shoulder in what seemed to be more bad luck than anything, was given a two-minute boarding minor.
Bruins general manager Peter Chiarelli said the following in a statement:
“Johnny Boychuk  has been taken to Montreal General Hospital for observation, after being injured in Thursday’s game against the Canadiens. Before he was transported to the hospital, he was able to demonstrate movement in all of his extremities. We will provide a further update when it is appropriate.”
The game marked the the fourth time this season the Bruins have had to play the majority of the game with only five defensemen, as injuries to Boychuk (Oct. 31), Adam McQuaid (Nov. 9) and Dennis Seidenberg  (Nov. 19) have left the B’s down a blueliner.
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