Frenchman Helan, on loan from Manchester City, sat out last week's goalless FA Cup stalemate with MK Dons following his two yellow cards in the recent draw at Huddersfield.
But Wednesday will be without fellow midfielder David Prutton, who starts his two-game ban for reaching 10 yellow cards.
Manager Dave Jones, who has no other new injury or suspension worries, recalled goalkeeper Stephen Bywater, skipper Martin Taylor and striker Chris Maguire last week and must decide whether to retain them in his starting line-up.
In-form defender Anthony Gardner and goalkeeper Chris Kirkland are expected to return, while Gary Madine, Chris O'Grady and Jermaine Johnson are all vying with Maguire for a place up front.
Three straight wins over the Christmas period temporarily lifted the Owls clear of the bottom three, but after being held at Huddersfield, a home defeat to Burnley in their last match saw them slip back into the relegation zone.