The Chicago Bears have placed wide receiver Johnny Knox on the physically unable to perform list, according to Vaughn McClure of the Chicago Tribune. By placing him on the PUP list, Knox will be able to participate in team meetings and use team facilities, but he can't actively practice on the field with the team.

On Dec. 18 of last year, Knox collided with Seattle's Anthony Hargrove and suffered a major back injury after literally being bent backwards on the play. The injury ended up requiring surgery, and at this point there's not an established timetable for the wideout's return.

For the time being, Knox can be placed back on the active roster at any time. If he's still on the PUP list at the beginning of the regular season, he'll be forced to sit out the first six games of the season.

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