The Manchester City midfielder is ineligible for the Owls having already appeared in the competition for Shrewsbury, where he was on loan earlier in the season.
Fellow midfielder David Prutton will also be missing as he sits out the second of a two-game ban for reaching 10 yellow cards.
Manager Dave Jones has no major new injury or suspension problems, but faces a series of selection posers after making six changes to his starting line-up for Saturday's win at Hull.
Giles Coke returned to midfield for his first league start of the season and is expected to retain his place, while Jose Semedo and Paul Corry could return in Helan's absence.
Gary Madine and Chris O'Grady played no part at the weekend and are also pushing for recalls, while Jones must decide whether to stick with Chris Kirkland in goal - he saved a late penalty at the KC Stadium - or bring back Stephen Bywater.