Castonzo (knee/ankle) is questionable for the Colts' Week 16 matchup against the Steelers, Andrew Walker of the Colts' official site reports.
Castonzo has dealt with a knee injury since Week 12 but was able to play all 54 snaps against the Texans in Week 15. Though he seemed to be on a positive trajectory, Castonzo reportedly picked up an additional ankle injury in the lead-up to Week 16. He was unable to practice on Friday as a result, leaving his status for Sunday in doubt.