Luatua dislocated his left shoulder, suffering associated nerve damage, during the Blues' win over the Bulls in May.
He was subsequently ruled out of the Blues' last three matches of the season.
The 14-test All Black has to decide whether to have surgery now to fix the problem or try to get through to the global tournament.
"He'll possibly need an operation on his shoulder, so he will be out until next season," Blues coach Sir John Kirwan said.
"He could force his way back but it would be at the limit. It's getting the operation and getting the recovery done."
Luatua (24) is continuing to get medical advice and is expected to make a decision next week.
Fellow All Blacks and Blues forward Patrick Tuipulotu is one player who is already destined to miss the World Cup because of surgery.
The 22-year-old seven-test lock is having operations on both his hips, putting him out of rugby for the rest of the year.
Kirwan said the decisions before the likes of Luatua and Tuipulotu were tough ones.
He said Luatua faced the danger of the shoulder popping out any time if he delayed the operation.
"With someone like Patrick, he's got a 15-year career ahead of him so he's got to make sure he looks after himself and gets himself right," he said.
"It's a big decision, especially in World Cup year."
