Reader (shoulder) was a non-participant in Wednesday's week-opening practice session.
Reader missed last Thursday's win over the Packers due to a shoulder injury, and his absence in the Lions' first practice this week casts a cloud over his status for Sunday's matchup versus Buffalo. Levi Onwuzurike (hamstring), who also missed the contest versus Green Bay, was able to log a limited practice Wednesday, and he could be in line for a healthy dose of defensive snaps Sunday if he's able to return to action and Reader has to sit out another game.