Brown suffered a broken right foot in a Nov. 3 loss to Washington and Hutchinson broke his left leg in a Sept. 15 defeat to Arizona.
It has been a nightmarish season for the Seahawks, who lost star quarterback Trent Dilfer for the rest of the season with a torn Achilles tendon and middle linebacker Isaiah Kacyvenski for four to six weeks with an ankle injury.
Brown, 32, had been one of the few bright spots for the Seahawks, leading the club with seven sacks in eight games.
Earlier this season, he signed a five-year contract extension worth a reported $28.5 million.
One of the league's better pass-rushing linebackers, Brown joined the Seahawks as a free agent in 1997, a year after registering 13 sacks with the Pittsburgh Steelers. In 142 NFL games, including 135 starts, Brown has 71 sacks.
The Seahawks signed veteran linebacker Terry Killens to help offset Brown's loss.
From 1996-2000, Killens played in all but two games for the Houston Oilers-Tennessee Titans. He spent the 2001 season with the San Francisco 49ers and was signed last March by the Denver Broncos, who released him before the season.