Parker suffered the injury -- in which the shoulder pops out of joint and immediately pops back in -- during a 23-6 victory over the Washington Redskins on Nov. 3. Parker is being fitted for a harness and will focus on strengthening the muscles around the shoulder to prevent reinjury.
"We weren't able to let [Parker] go last week, but it's our intention to let him go and practice this week and play for us this weekend," Tomlin said.
With rookie Rashard Mendenhall out for the season with a broken shoulder, Mewelde Moore has been Pittsburgh's featured back in three of the past four games. Although he has scored six touchdowns, the Steelers' rushing offense has struggled in recent weeks, totaling only 214 yards on the ground the past three games.
The return of left tackle Marvel Smith could help the running game. Smith hasn't played since Oct. 5 because of a back injury, but Tomlin said it's possible he will practice this week. Smith had a favorable workout Tuesday, Tomlin said.
"He's missed some time. Not only in terms of health, but technically he's got to be up to speed," Tomlin said. "He's got to knock the rust off quickly if he's going to play for us this weekend."
Steelers quarterback Ben Roethlisberger continues to deal with his injured right shoulder and was described as day to day. If Roethlisberger is able to practice this week, Tomlin said he likely will start Sunday.
Tomlin indicated that Roethlisberger would have to practice more this week if he's going to play, pointing out timing and cohesion issues in the Colts game.
"It's important that you practice and get physical reps," Tomlin said. "One of the things we've been dealing with in regards to his situation is a little short-term misery, if you will."
Tomlin applauded Roethlisberger for taking accountability for the defeat against Indianapolis and hinted that the blame for the interceptions could also fall partly on intended receiver Santonio Holmes. But the coach did not completely absolve his quarterback, who has thrown more interceptions (11) than touchdowns (10) this season.
"It wasn't a winning performance," Tomlin said. "That's the reality of it. We've got to take care of the football, and we didn't do it. They had interceptions and we didn't."
Steelers starting tight end Heath Miller (ankle) also is not expected to play this week, Tomlin said.
James Walker covers the AFC North for ESPN.com. Information from The Associated Press was used in this report.