The 23-year-old had missed the previous four games after suffering a concussion in a 5-2 win over Tampa Bay on December 10.
He started skating on Sunday and was back to full contact for Monday's practice. Following Tuesday's skate, he was listed as day-to-day.
The injury occurred in the second period of the game against Tampa Bay when the knee of teammate Wayne Simmonds hit the back of Giroux's head.
Three days later, he was listed as indefinitely out with the concussion.
Despite missing the past four games, he still sits atop the NHL in points with 39 as he has 16 goals and 23 assists. Toronto's Phil Kessel, Pittsburgh's Evgeni Malkin and Vancouver's Henrik Sedin each also have 39 points.