Abdull sustained the issue in KR's Challenge Cup semi-final defeat by Huddersfield Giants last weekend and a consultant has since confirmed that he suffered a significant tear as well as ligament damage.
The half-back is set to undergo surgery which could end his hopes of featuring for England in the World Cup later this year.
"It can either be a lengthy repair by itself and not guaranteed it's going to recover or a lengthy repair with surgery that is going to be more of a guarantee and that's where it's at," said Smith.
"The upshot is Jordan will most likely get the operation which will end his season.
"It's about a 16-week recovery from that operation so it's a blow, certainly for Jordan and us.
"He could get back slightly quicker [without surgery] but the advice is it's far safer to go with an operation so he'll more than likely do that.
"It's a tough one for Jordan. Any year, they just want to play rugby so whether it's their country, their club, they just want to play."
The loss of Abdull will be offset by the return of Mikey Lewis in the next two to three weeks, while Elliot Minchella's injury is not as bad as first feared.
The loose forward sustained ankle ligament damage in the game against Huddersfield but he is in a group of players who could be back in the next week or two.
"The good news is that while Elliot Minchella's scans weren't great, his actual functions are great and he's likely to miss a week," added Smith.
"Frankie Halton is close and Luis Johnson is back. Sam Wood will be back next game and we've got Albert Vete coming off suspension.
"Lachlan Coote is ready to go and Mikey Lewis should be back in the next two to three weeks."