The French winger signed from Rennes after spending the second half of last season recovering from separate knee and groin problems.
Marveaux was then struck down with his latest injury in November and had to undergo an operation.
The 25-year-old was initially scheduled to return around March, but, despite making progress in his rehabilitation, he is concerned he may not play again this season.
Like former Toon striker Michael Owen, the Frenchman has a history of being injury-prone, and already he looks as though he won't be regular in the side.
He took months before he was blooded in the Premiership because of various problems, and some suggest the English league is "too tough" for him.
Sylvain Marveaux: "I don't know if I will play again this season, because I won't train for two more months.
"I'm not thinking of playing again. I want to do it step by step.
"It's getting better now. I'll start running next week.
"The worst - surgery and everything - is behind me, and I just want to be on the pitch.
"I hope I will train in a couple of months."