The recovery is expected to take eight weeks, which means that his season is very likely finished.
McQuaid hasn't played since Jan. 20 because of a quad injury. He had been seen skating with the Bruins a couple of weeks ago but it appears he had another issue pop up with surgery on his ankle.
Boston has been dealing with injuries on the blue line all season, the biggest a knee injury to Dennis Seidenberg that has kept out for the majority of this season.
With the injuries the Bruins have had to rely more on their young group of defensemen and they've responded well with Torey Krug and Dougie Hamilton playing well. Kevan Miller has also been good for the Bruins in the pinch, filling the third-pairing role of McQuaid admirably this season.