The Premier League club confirmed on Friday that the latest scan showed the injury is less severe than first feared, with bruising to the bone and soft tissue damage the extent.
Depending on the speed of recovery the defender could be fit as early as the beginning of April, with Newcastle's Europa League quarter-final at Benfica a possibility.
A statement on the club's official website said: "Massadio will continue to be assessed over the coming days. He has been very lucky that he has not suffered more serious injury.
"This positive diagnosis in no way lessens the club's views with regard to the severity of the tackle from which it resulted."
McManaman was not penalised by referee Mark Halsey at the time, with the Football Association later ruling that they could not take retrospective action as at least of the match officials had seen the incident.
That infuriated Newcastle, with managing director Derek Llambias telling the governing body that their disciplinary process was 'not fit for purpose'.