United had said to have been very keen on the switch but chose not to pursue it when the injury was sutained.
Joe Gamble has now returned to train with the Royals and once fit will be available for selection. However, Alan Pardew has seemed reluctant to play his talented young midfielder thus far.
Carlisle, who came out of administration last week, have brought in four new players now that funds are available enabling them to do so.
Leon Osman, Craig Farrell, Mark Magennis and John Sutton, brother of Chris Sutton at Celtic, have all signed for the Brutton Park based side.
Sutton, Osman and Farrell have all signed on loan meaning it is unlikley that Gamble will head north even when he returns to fitness as there is a limit to the number of loan signings a club can have at any one time.
Meanwhile, Reading assistant boss Kevin Dillon has confirmed that Adi Viveash could shortly complete a permanent transfer to Oxford United.