Roberts, 35, has not featured for Reading since a 1-0 defeat at Southampton on December 8 and admits he has no timeframe on a comeback with Brian McDermott's side currently 18th in the table.
"It's going slowly with the hip and there is no real time line on it," he told the Reading Post.
"I'll keep working on the training ground to get it right.
"It's not cut and dried, that's the nature of the injury. We're working as hard as we can to try and get it right.
"We've exhausted everything we can to try and make it right. If there is an opportunity of us managing it, then we certainly will do."
Grenada international Roberts has also urged Reading to continue to play their usual game as they look to remain a top-flight side.
"There are still big games to go and it doesn't change what we need to do," he said.
"We need to be positive. We attack every game with a positive attitude and there is no other way."