Campbell remained in the game.
The Bears are already without Jay Cutler, who was ruled out with a concussion.
Campbell was scrambling to the left side of the field looking for a receiver when 49ers linebacker Ahmad Brooks came from behind and stripped him of the ball, which fumbled its way out of bounds.
Campbell stayed on the ground after being tackled. The Bears medical personnel came onto the field to tend to him for a couple of minutes. It appeared as if it was Campbell's shoulder was hurt but the team doesn't have to make an announcement since he didn't leave the game.