Johnson returning to Birmingham training
"But we expect him to step up his rehab and start training again this week.
"It will be good to have him back in contention and we were certainly short in numbers in the midfield area during the early part of the season.
"Fabrice Muamba and Mehdi Nafti ran themselves into the ground for the opening two games against Chelsea and Sunderland but, because Jonty and Johan Djourou were injured, I couldn't really change it against West Ham and it told on us."
Defender Rafael Schmitz, signed on a season-long loan from Lille, is also set to begin training this week after being laid low with an Achilles problem.
Bruce confirmed: "We expect Rafael to be training this week as well."