ALLEN PARK — Lions coach Jim Caldwell explains the shortfall with the offense without using injuries as an excuse.

“We have no comfort zone, we have no area in which we’re comfortable with at this point in time with our offense,’’ Caldwell said on Tuesday morning. 

The offense hasn’t scored a touchdown in two games.

— Reggie Bush has missed four of the last six games with an injured ankle and it’s uncertain if he will return on Thursday. Caldwell said, “We’ll see.” The run game has under-performed most of the season and is rated 30th in the league. Since Week 4 the Lions have had just two games where Bush and Joique Bell were both active.

— Calvin Johnson has played three games since coming back from an ankle injury but his production has been down.

“I think the biggest thing you can take a look at: Does he still run by people? The answer to that would be yes. Does he still lay out and catch the ball and things he normally does? That would be yes. I think that’s what matters,’’ Caldwell said.

— The coach offered no updates on Riley Reiff (knee) or Ashlee Palmer (concussion). Practice begins at noon today.

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