Brown is active after being out since suffering the injury in a loss to New England on Dec. 17. He missed the final two games of the regular season.
The Steelers were set to play the Jacksonville Jaguars on Sunday afternoon, with the winner facing the Patriots in the ACF title game.
Brown, who was listed as questionable this week, caught 10 passes for 157 yards when Pittsburgh lost to the Jaguars 30-9 on Oct. 8. He led the NFL with 1,533 yards this season.
Also active for Pittsburgh are defensive end Stephon Tuitt, who was been bothered by an elbow injury, and cornerback Artie Burns, who has been dealing with a knee injury.