Helander (knee) has been ruled out of Gers' final three games of the season – starting with the Celtic clash – after limping off during last week's Scottish Cup defeat to St Johnstone.
Scott Arfield (ankle) has also been told his season is over as he joins Ryan Jack (calf), Leon Balogun (Achilles) and Nikola Katic (knee) on the casualty list. Nathan Patterson, Bongani Zungu and Calvin Bassey are still suspended.
Defender Christopher Jullien is out long term with a knee injury.
Captain Scott Brown will play in his last Old Firm game before joining Aberdeen as player/assistant next season.