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 injured reserve with a hip injury.
Bears coach Matt Nagy said on Monday that it's possible Hicks could return later this season from his injury. 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, missing the Week 4 game vs. the Vikings with a right knee injury.
Hicks, in his eighth NFL season, has 33.5 sacks in his career.