Top scorer Michu has a hamstring problem and may miss the remainder of the campaign as a result of the injury.
Goalkeeper Vorm is a doubt after suffering a head injury in the 3-2 win at Wigan Athletic on Tuesday.
Boss Michael Laudrup could be boosted by the return of midfielder Ki Sung-Yueng following a dead leg for the trip to Old Trafford.
Graeme Murty admits he faces an Old Firm dilemma after watching Jason Cummings fire himself into derby contention with his first ever senior hat-trick.
Fiorentina captain Davide Astori has sadly died at the age of 31.