Knox didn't practice Wednesday due to foot and hamstring injuries, Chris Brown of the Bills' official site reports.
Heading into Week 4 action, Knox had been limited by back and hip issues, but the tight end suited up this past Sunday against the Ravens and recorded 48 snaps on offense while catching three of his six targets for 40 yards. Now that Knox is contending with a pair of new injuries, his status will need to be monitored ahead of this weekend's game against the Steelers.