The Chicago Tribune first reported the extent of Wootton's injury.
Wootton hurt the knee covering the opening kickoff of the Bears 10-3 preseason victory over the Buffalo Bills on Saturday night. He was immediately ruled out for the rest of the game.
The belief is Wootton might be healed in time to return for the Bears regular-season opener Sept. 11 against the Atlanta Falcons.
This is a disappointing development for Wootton, who had a strong first two weeks of training camp and was making a push to solidify himself as the Bears third defensive end behind starters Julius Peppers and Israel Idonije. The defensive end was still recovering from a torn ACL he suffered while at Northwestern when he reported to camp last summer. Wootton ended up being inactive in 10 of the Bears first 12 regular season games.
"Being a rookie last year was kind of a whirlwind with learning the defense and the expectations," Wootton said earlier in camp. "I just wasn't as confident as I am this year. I think the biggest difference is confidence. The improvements I've made with my strength and my quickness, just getting everything back after my knee surgery."
Completely healthy when the Bears reported to Bourbonnais at the end of July, the 2010 fourth round draft pick had recently drawn positive reviews from defensive coordinator Rod Marinelli.
"I like what Wootton has done so far in camp," Marinelli said. "He's really trimmed himself down. He looks quick, looks fast. He's got great tempo, he's smart. I really think the more you do something, the better you get. Just doing it over and over."
Wootton's absence the next few weeks should allow the Bears to get a closer look at free agent defensive end Vernon Gholston.
Jeff Dickerson covers the Bears for ESPNChicago.com and ESPN 1000.