Aikman said that while there was no reason Romo could not recover fully, the fact that he has had two injuries in the space of a year would make it more difficult to do so.
"I came back in a relatively short period of time because of when I had my surgery, so he's at least afforded more time to get ready," Aikman told the club's official website. "But having said that, two back surgeries in less than a year at his age, I would be a bit concerned.
"I'm hopeful that he's able to come back – everybody is. This team won't be the same if he's not able to. I anticipate that he will come back. But to say that, 'Hey, he's ahead of schedule and everything's going fine,' I'm not sure how you can really measure that here in April."
Romo has spent his entire career with the Cowboys since being drafted in 2003.