Njoku was limited at practice Wednesday due to a knee issue, Mary Kay Cabot of The Cleveland Plain Dealer reports.
In his return to action from a wrist injury in the Week 14 win over the Bengals, Njoku played 20 out of the Browns' 54 offensive snaps, catching one of his three targets for a four-yard gain. Now the tight end is contending with a new injury, but at this stage it's unknown whether he's dealing with something minor or managing an issue that cropped up at practice Wednesday.