The 19-year-old was hurt in a clash of heads with teammate Steve Ward late in the first half.
He was tended to by both clubs’ medical teams before being taken from the field by stretcher after a 13-minute delay to the game.
A statement on Rhinos’ website, issued on Saturday morning, said: “The early signs are he has some muscle and tendon damage around his neck area, but it is thought, as this stage, it is not serious or long term. He also sustained a heavy concussion.
“The Rhinos medical team have been with him throughout and he is recovering in hospital now, but will be released later on Saturday.”
It added: “On behalf of Mikolaj, we would like to thank the many well wishers who have messaged their support for him following the injury.
“We would also like to thank all the medical staff, including our own team and the staff from Huddersfield Giants, who helped to treat Mikolaj on the field and in hospital.”
Oledzki has been one of the successes of Rhinos’ disappointing season and last night was his 14th appearance.
He was one of three Rhinos players injured during the game.
Stand-off Jordan Lilley rolled an ankle and half-back Richie Myler suffered concussion for the second time in four games.
All three are are set to miss next Friday’s visit of Betfred Super League leaders St Helens.
Coach Brian McDermott said stand-off Joel Moon (Achilles) and second-row Carl Ablett (calf) could come back into contention, along with Brad Dwyer and Jack Ormondroyd who are set to feature for Featherstone Rovers against Dewsbury Rams on Sunday.