It's the second straight day that the Bears have placed a key player on injured reserve. On Monday, guard Kyle Long was placed on IR with a hip injury.
Bears coach Matt Nagy confirmed Wednesday that Hicks is a candidate to return in eight weeks. Nagy also said Hicks is not expected to need surgery.
If the Bears choose to designate him to return later this season, the earliest he'd be eligible to play in a game would be in Week 15.
The Bears might replace Hicks in the lineup with defensive tackle Bilal Nichols, who has been sidelined since Week 2 with a broken hand. He practiced Monday and will wear a cast to play in games.
Nichols said Monday that he is getting "a lot of insight" from linebacker Leonard Floyd, who wore a cast while playing last season.
Hicks, 29, was selected to his first Pro Bowl in 2018 when he had 7.5 sacks, three forced fumbles and 55 tackles while starting all 16 games. He has one sack and six tackles in four games this season; he missed the Week 4 game vs. the Vikings with a right knee injury.
Hicks, in his eighth NFL season, has 33.5 career sacks.
ESPN's Jeff Dickerson contributed to this report.