Backes, 32, missed the Bruins' 5-0 loss to the Minnesota Wild on Tuesday at TD Garden and will not be in the lineup for Wednesday's game against the New York Rangers or Saturday's game against the Detroit Red Wings.
"David Backes underwent the removal of the olecranon bursa from his elbow on Monday, Oct. 24. His condition will be updated after the weekend," general manager Don Sweeney said in a statement released by the team.
The bursa is a liquid filled sac that provides cushion against the pointy bone in the elbow. If it is infected or badly damaged it can be removed and will grow back within a few months.
Backes, who signed with the Bruins as a free agent during the offseason, has two goals and two assists for four points in five games for Boston this season.
Forward Austin Czarnik has been recalled from Providence of the AHL to take Backes' spot.