The midfielder was allowed to link up with the Rams in January by parent club West Bromwich Albion.
The idea was for the 21-year-old to gain useful experience in the Championship over the remainder of the campaign before returning to The Hawthorns ready to push for first-team recognition - with a new contract proving how highly he is regarded by the Baggies.
Thorne is, however, yet to make his Derby debut.
He is part of Steve McClaren's plans, though, with assistant manager Paul Simpson assuring the youngster that his opportunity will come.
He told the Derby Telegraph: "George has been brought in as an extra midfield player to give us cover but the way John Eustace, Craig Bryson, Will Hughes and Jeff Hendrick have done, George is having to be patient.
"We have 16 games to go and there is every chance he is going to get an opportunity.
"We are going to pick up knocks and possibly suspensions. John Eustace is on nine bookings.
"Something will happen and then, hopefully, George will slot straight into the position he has been asked to play."