The team announced that Shazier had been taken to the hospital for further evaluation on his back. He would not return to the game and there would be no further updates at the time.
Shazier, the Steelers' leading tackler through 11 games, was injured while making a tackle Bengals wide receiver Josh Malone with 11:14 remaining in the first quarter.
The fourth-year linebacker remained mostly motionless while he was attended to by trainers, but he did lift his own head at one point.
Shazier led the Steelers in tackles in seven of the team's first 11 games.