The Ducks got Parros from the Colorado Avalanche in exchange for a second-round draft pick in 2007. Anaheim traded Chistov to Boston in exchange for a third-round draft choice in either 2007 or 2008 and sent Fedoruk to Philadelphia for a fourth-round draft pick in 2007.
The moves cleared US$800,000 of payroll from Anaheim's books. They added Parros' $450,000 salary while losing Fedoruk's $450,000 and Chistov's $800,000.
Parros appeared in just two games with the Avalanche this season after being claimed off waivers from Los Angeles last month. The 27-year-old was minus-1 with no penalty minutes.
Chistov returned from Russia this season to rejoin Anaheim and only got into one game. The 23-year-old was held scoreless and had one goal in three American Hockey League games this season.
"He's an offensive player and he's had some success in the past," Bruins GM Peter Chiarelli told The Canadian Press. "He's going to help our top three lines. We've had trouble scoring goals so far this season."
Fedoruk returns to Philadelphia after three years in Anaheim. He missed the last eight games with a broken cheekbone after appearing in the first 10 games for the Ducks. The 27-year-old had three assists and 36 penalty minutes in those games.