Lehtonen started experiencing the soreness after Wednesday's morning skate in Chicago. He was expected to start against the Blackhawks, but was held out of the game.
"He's improving. He may be an option for us [Friday] but we'll probably again be real careful," said Stars coach Marc Crawford. "Unless he is 100 percent, we have to be prudent and sure and just do the right thing. We recognize that it's nothing structurally with him. He's got some soreness and that's going to happen every now and then. I think anybody who has had back surgery or the complications that come with it, knows that it is not about the structure. It's sometimes about how you sleep or you are going to have some soreness. We have to stay diligent with it, he's been diligent with [it], our trainers have been diligent with it and our medical people have been diligent with it.
"We're confident that he's going to come back and play a lot. We know that he's capable to playing lots of games, but we can't overburden him. And this isn't a case where we have. We had scheduled to play [Andrew] Raycroft in the Carolina game anyway. So, we've really managed the schedule with him in mind. ... Every once in a while you are going to have a bump and this is a bump. We'll deal with it."
Lehtonen, who has started 22 of 27 games this season, said he's had the soreness before, but it came during a time when the Stars weren't playing quite as heavy a schedule.
"I am feeling better," Lehtonen said. "I had the same thing a couple months ago, but we didn't have games every other day, so we were able to take a couple days easy and it was fine. Hopefully it's the same way. It's already a lot better than yesterday."
Lehtonen said playing on Friday against Carolina is a possibility.
"We'll see," he said. "If I feel good I want to play. I am going to talk with [the trainers] tonight and then tomorrow morning we'll see where we are at."
Crawford said goalie Richard Bachman, who was called up to serve as a backup to Raycroft for Wednesday's game, will stay with the team for now.
Toby Petersen, who has been out with a hand injury, said he is getting close but is not quite there yet.
Mark Stepneski covers the Stars for ESPNDallas.com.