The centre half, who joined Birmingham from City and has been a regular of Alex McLeish's team for the last two seasons, has a severe hamstring problem.
Alex McLeish is quoted by the Press Association as saying: "I think it will be a long shot for Scott to be back before the end of the season.
"Nothing has been totally confirmed yet but we are going to miss him for a long time. "It's a blow and we wish the big fellow a successful recovery first and foremost."
