Cunningham has been diagnosed with a high-ankle sprain, Larry Mayer of the Bears' official site reports.
Cunningham was carted to the locker room during Sunday's loss to Atlanta, finishing with one kickoff return for 23 yards. He only logged four snaps on offense while serving as the No. 3 running back behind Jordan Howard and Tarik Cohen. With Cunningham likely to miss time, undrafted rookie Taquan Mizzell could be active for Sunday's game in Tampa Bay.