Luukkonen is considered week-to-week after stopping seven of nine shots in the first period Tuesday before suffering a lower-body injury in a 6-1 loss to Tampa Bay. Subban finished the game but has been diagnosed with what the team calls an upper-body injury that is expected to sideline him for at least a month.
Houser was signed to an NHL contract after spending this season splitting time between Buffalo's minor league affiliates in Rochester and Cincinnati. The 29-year-old made his NHL debut with the Sabres last season, going 2-2 in four games.
The Sabres are 0-4-2 in their past six and have won just three times in their past 20 (3-13-4). Buffalo plays at Nashville on Thursday night.