The Chronicle understands the diagnosis of the No 9’s injury picked up against Swansea City proved to be a broken kneecap which is likely to require an operation.
He will now miss games with Arsenal, Cardiff City and Liverpool and face a summer of rehab.
Cisse discovered the bad news after a scan yesterday.
The injury also means he could be struggling to be fit for pre-season when the Magpies return to their Benton base in early July.
Cisse’s absence now means Pardew has only Loic Remy, Shola Ameobi and de Jong to work with in the remaining games of the season.
He cannot recall young Geordie striker Adam Campbell from St Mirren as cover with the player contracted to the Paisley club until July 1.
St Mirren’s season finishes on May 10 and even though United have a game with Liverpool they are not permitted to bring Campbell back as cover a day later due to the nature of his long-term loan deal with the Buddies.