Christiansen (upper body) has been ruled out for Saturday's home game against the Capitals, Jeff Svoboda of the Blue Jackets' official site reports.
The 25-year-old suffered an upper-body injury during Thursday's win over Buffalo, and while head coach Dean Evason doesn't yet have a timetable for Christiansen's return, he'll be unavailable for at least one game. The Blue Jackets have just three regular-season games remaining after Saturday's matchup, and it's not yet clear whether Christiansen will be able to suit up in any of those contests.