Moussa, 21, could yet be involved in today’s game at Swansea City but needs to be registered before the Football League’s noon deadline.
Manager Sean O’Driscoll had already signed Blackpool striker Jason Euell on a month’s loan in the wake of his side’s humiliating 6-0 defeat by Ipswich Town in midweek.
Moussa, a former Belgian youth international, has started only four games since moving to Leicester last summer from Southend United.
Rovers are in the middle of a major injury crisis with striker Billy Sharp (groin) and defender James O’Connor (broken metatarsal) the latest additions to the list.
Boss O’Driscoll said: “It was always going to be tough this season but when you have 13 players on the treatment table, common sense tells you that an already difficult situation becomes impossible.”