The Ravens, who are deep at linebacker, announced the move this afternoon.
The 6-foot-3, 247-pound Burgess, who enters his third NFL season, worked at both inside and outside linebacker for the Ravens. He also was a regular on the Ravens' special teams units.
The 25-year-old Burgess has appeared in 10 career NFL games, with no starts. He was selected by the Ravens out of Michigan in the sixth round of the 2007 draft.
Injuries have limited Burgess' playing time over the first two years of his NFL career. After appearing in eight games as a rookie, he landed on injured reserve (quad), and then missed the entire 2008 season because of a broken forearm. He suited up in the Ravens' first two games this season.
The Patriots are dangerously thin at linebacker, which has limited their ability to scheme.
Leading tackler Jerod Mayo remains sidelined with a sprained right medical collateral ligament, and the team previously lost third-round draft choice Tyrone McKenzie (torn ACL) and second-year player Shawn Crable (groin) to season-ending injuries.
In Sunday's 16-9 loss to the Jets, the Patriots played most of the game with just two linebackers -- second-year man Gary Guyton and 10-year veteran Adalius Thomas -- in a 4-2-5 alignment. Four-year veteran Pierre Woods was the team's third linebacker.
To make room for Burgess on the 53-man roster, the Patriots released center Ryan Wendell.