Barber dislocated his right little toe in the first half against Seattle on Nov. 27 and did not practice all week. Choice, from Georgia Tech, replaced him against Seattle and rushed for a career-high 57 yards on 11 carries, giving him 147 yards on 30 carries this season.
Dallas (8-4) was already without backup running back Felix Jones due to a season-ending torn ligament in his left big toe -- an injury that occurred while he was rehabilitating a left hamstring injury.
Losing the 225-pound Barber is a major setback for the Cowboys, who may need to win at least three of their final four games to reach the playoffs. The Steelers (9-3) lead the NFL in rushing defense with a 71.2 yards per game average, the lowest by any team since the 1970 NFL merger, and have not allowed an opposing back to gain even 80 yards.
Barber, who missed a 1,000-yard season by 25 yards last season, has 225 carries for 870 yards, seven touchdowns and a 3.9 yards per carry average. He was hoping to play by wearing a splint on the toe or a shoe insert, but did not progress as quickly as coach Wade Phillips hoped.
Phillips said as late as Thursday that Barber's status probably wouldn't be decided until game time.
Copyright 2008 by The Associated Press